U.S. Fish & Wildlife Service Draft Revised Recovery …...Second Draft Revised Recovery Plan for Hawaiian Waterbirds, 2nd Revision • May 2005 ii Acknowledgments Parts I and II of

U.S. Fish & Wildlife Service

Draft Revised Recovery Planfor Hawaiian WaterbirdsSecond Draft of Second Revision

Clockwise from upper left:Hawaiian ducks, Hawaiian stilt,Hawaiian common moorhen, and Hawaiian coot.©Eric A. VanderWerf. Used with permission.

Draft Revised Recovery Planfor

Hawaiian Waterbirds,Second Draft of Second Revision

(May 2005)

(Original approved 1978; First Revision approved 1985;First Draft of Second Revision released May 1999)

Region 1U.S. Fish and Wildlife Service

Portland, Oregon

Approved: XXXXXXXXXXXXXXXXXXXXXXXXXXRegional Director, Region 1

U.S. Fish and Wildlife Service

Date: XXXXXXXXXXXXXXXXXXXXXXXXXX

Second Draft Revised Recovery Plan for Hawaiian Waterbirds, 2nd Revision • May 2005

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DisclaimerRecovery plans delineate reasonable actions that are believed to be required to

recover and protect listed species. We, the U.S. Fish and Wildlife Service, publishrecovery plans, sometimes with the assistance of recovery teams, contractors, Stateagencies, Tribal agencies, and other affected and interested parties. Objectives will beattained and any necessary funds made available subject to budgetary and otherconstraints affecting the parties involved, as well as the need to address other priorities. Recovery plans do not obligate other parties to undertake specific actions and may notrepresent the views nor the official positions or approval of any individuals or agenciesinvolved in recovery plan formulation, other than our own. They represent our officialposition only after they have been signed by the Regional Director or Director asapproved. Recovery plans are reviewed by the public and submitted to peer reviewbefore we adopt them as approved final documents. Approved recovery plans are subjectto modification as dictated by new findings, changes in species status, and the completionof recovery actions.

Notice of copyrighted material:Permission to use copyrighted images in this recovery plan has been granted by

the copyright holders. These images are not placed in the public domain by theirappearance herein. They cannot be copied or otherwise reproduced, except in theirprinted context within this document, without the written consent of the copyright holder.

Literature citation of this document should read as follows:U.S. Fish and Wildlife Service. 2005. Draft Revised Recovery Plan for Hawaiian

Waterbirds, Second Draft of Second Revision. U.S. Fish and Wildlife Service,Portland, Oregon. 155 pp.

Electronic copies of this document will be made available at:• http://pacific.fws.gov/ecoservices/endangered/recovery/default.htm• http://endangered.fws.gov/recovery/index.html


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Acknowledgments

Parts I and II of this recovery plan were drafted in 1997 for the U.S. Fish andWildlife Service by Andrew Engilis, Jr. (then of Ducks Unlimited, currently ofUniversity of California, Davis) and Dr. Frederic A. Reid of the Western Regional Officeof Ducks Unlimited. Modifications were made by Dr. Ann Marshall of the U.S. Fish andWildlife Service, which resulted in the Draft Revised Recovery Plan for HawaiianWaterbirds Second Revision dated May 1999. Since then, substantial revisions to thedraft plan have been made by Leilani Takano and Dr. Eric VanderWerf of the U.S. Fishand Wildlife Service, including the addition of figures illustrating the population trend ofeach species and maps showing their abundance and distribution on each island. Theprimary authors of this second draft revised plan are Andrew Engilis, Jr., Dr. AnnMarshall, Dr. Frederic A. Reid, Leilani Takano, and Dr. Eric VanderWerf.

For valuable input and constructive comments on waterbird recovery issues wethank J. Michael Reed of Tufts University, Kim Uyehara, Sharon Reilly, and JenniferCrummer of Ducks Unlimited; Fern Duvall, David Smith, John Polhemus, and MeyerUeoka of the Hawaiì Department of Land and Natural Resources Division of Forestryand Wildlife; and U.S. Fish and Wildlife Service employees Karen Gabble, ColleenHenson, Nancy Hoffman, Susan Machina, Mark Metevier, Lynda Myashita, ArlenePangelinan, Gina Shultz, Mike Silbernagle, Gordon Smith, Chris Swenson, Ron Walker,and Marilet Zablan for valuable insights into waterbird recovery needs, assistance withgraphics, and review of the recovery plan. We also thank the Hawaiì Division ofForestry and Wildlife for providing the biannual waterbird count data and the HawaiìNatural Heritage Program for compiling the data.


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Executive Summary

Current Species Status: This second draft revised recovery plan addresses fourspecies of Hawaiian waterbirds: the Hawaiian duck or koloa maoli (Anas wyvilliana),Hawaiian coot or àlae keòkeò (Fulica alai), Hawaiian common moorhen or àlae ùla(Gallinula chloropus sandvicensis), and Hawaiian stilt or aeò (Himantopus mexicanusknudseni), all listed as endangered. Historically, these four species were found on all ofthe main Hawaiian Islands except L~naì and Kahoòlawe. Currently, Hawaiian ducksare found on the islands of Niìhau, Kauaì, Oàhu, Maui, and Hawaiì; Hawaiian cootsand stilts are found on all of the main Hawaiian Islands except Kahoòlawe; andHawaiian common moorhens are found only on the islands of Kauaì and Oàhu. Population estimates based on the biannual waterbird count indicate the numbers of birdsfluctuate among years and that currently none of these species consistently number morethan 2,000 individuals, with the exception of the Hawaiian coot, but these estimates arereliable only for the coot and the stilt. Trend data collected over the past three decadesshow that Hawaiian coot, moorhen, and stilt populations are either stable or increasing. The status of the Hawaiian duck is difficult to judge due to the difficulty of distinguishingbetween Hawaiian ducks, feral mallards (Anas platyrhynchos), and hybrids. Hawaiiancommon moorhen numbers are difficult to estimate due to their secretive habits and useof densely vegetated wetland habitats.

Habitat Requirements and Limiting Factors: These endangered Hawaiianwaterbirds are found in a variety of wetland habitats including freshwater marshes andponds, coastal estuaries and ponds, artificial reservoirs, taro (Colocasia esculenta)patches, irrigation ditches, sewage treatment ponds, and in the case of the Hawaiian duck,montane streams and swamplands. The most important cause of decline of the fourspecies of endangered Hawaiian waterbirds is loss of wetland habitat. Other factors thathave contributed to waterbird population declines, and which continue to be detrimental,include predation by introduced animals, altered hydrology, alteration of habitat byinvasive nonnative plants, disease, and possibly environmental contaminants. Hunting inthe late 1800's and early 1900's took a heavy toll on Hawaiian duck populations, and to alesser extent on populations of the other three endemic waterbirds (Swedberg 1967). Currently, predation by introduced animals may be the greatest threat to the coot,moorhen, and stilt, and hybridization with feral mallards is the most serious threat to theHawaiian duck.

Recovery Priority Number: The recovery priority number for the Hawaiian duckis 2, on a scale of 1C (highest) to 18 (lowest; see Appendix D) reflecting a high degree ofthreat, a high potential for recovery, and the Hawaiian duck’s taxonomic rank as a full


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species. The moorhen and stilt each have a recovery priority number of 9, reflecting amoderate degree of threat, a high potential for recovery, and their taxonomic rank as asubspecies. The recovery priority number of 14 for the Hawaiian coot reflects a lowdegree of threat, a high potential for recovery, and taxonomic rank as a full species. TheHawaiian coot was considered a subspecies of the American coot (Fulica americana) atthe time it was listed, but it was recently split from the American coot and is nowregarded as a distinct species (Fulica alai; American Ornithologists' Union 1989).

Recovery Goal: The ultimate goal of the recovery program is to restore and maintainmultiple self-sustaining populations of these Hawaiian waterbirds within their historicalranges, which will allow them to be reclassified to threatened status and eventuallyremoved from the Federal List of Endangered and Threatened Wildlife and Plants.

Recovery Objectives: The recovery of the endangered waterbirds focuses on thefollowing objectives:

1) increasing population numbers to statewide baseline levels (consistently stableor increasing with a minimum of 2,000 birds for each species);

2) establishing multiple, self-sustaining breeding populations throughout eachspecies’ historical range;

3) establishing and protecting a network of both core and supporting wetlandsthat are managed as habitat suitable for waterbirds, including themaintenance of appropriate hydrological conditions and control of invasivenonnative plants;

4) for all four species, eliminating or controlling the threats posed by introducedpredators, avian diseases, and contaminants; and

5) for the Hawaiian duck, removing the threat of hybridization with feralmallards.

Recovery Criteria: For consideration of downlisting to threatened status, thefollowing conditions must be met:

Hawaiian Duck downlisting criteria

Criterion 1. All core wetlands listed in Table 10 on the islands of Kauaì,Oàhu, Maui, and Hawaiì are protected and managed in accordance with themanagement practices outlined in this recovery plan;


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Criterion 2. Of the supporting wetlands listed in Table 11 on the islands ofKauaì, Oàhu, Maui, and Hawaiì, at least 25 percent are protected and managedin accordance with the management practices outlined in this recovery plan;

Criterion 3. The statewide Hawaiian duck population shows a stable orincreasing trend at a number greater than 2,000 birds for at least 5 consecutiveyears;

Criterion 4. There are multiple self-sustaining breeding populations, withpopulations present on Kauaì, Oàhu, Maui, and Hawaiì; and

Criterion 5. The threat of hybridization with feral mallards is removed from allislands.

Hawaiian Coot downlisting criteria

Criterion 1. All core wetlands listed in Table 10 on the islands ofKauaì/Niìhau, Oàhu, Hawaiì, and Maui/Molokaì, are protected and managedin accordance with the management practices outlined in this recovery plan;

Criterion 2: Of the supporting wetlands listed in Table 11 on the islands ofKauaì/Niìhau, Oàhu, Hawaiì, and Maui/Molokaì/L~naì, 25 percent areprotected and managed in accordance with the management practices outlined inthis recovery plan;

Criterion 3: The statewide coot population shows a stable or increasing trend ata number greater than 2,000 birds for at least 5 consecutive years; and

Criterion 4: There are multiple self-sustaining breeding populations, withpopulations on Kauaì/Niìhau, Oàhu, Hawaiì, and Maui/Molokaì/L~naì.

Hawaiian Common Moorhen downlisting criteria

Criterion 1: All core wetlands listed in Table 10 on the islands of Kauaì andOàhu are protected and managed in accordance with the management practicesoutlined in this recovery plan;

Criterion 2: Of the supporting wetlands listed in Table 11 on the islands ofKauaì and Oàhu, 25 percent are protected and managed in accordance with themanagement practices outlined in this recovery plan;


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Criterion 3: The statewide moorhen population shows a stable or increasingtrend at a number greater than 2,000 birds for at least 5 consecutive years; and

Criterion 4: There are multiple self-sustaining breeding populations, withpopulations present on Kauaì and Oàhu, and on Maui/Molokaì and/or Hawaiì.

Hawaiian Stilt downlisting criteria

Criterion 1: All core wetlands listed in Table 10 on the islands ofKauaì/Niìhau, Oàhu, Hawaiì, and Maui/Molokaì, are protected and managedin accordance with the management practices outlined in this recovery plan;


Criterion 3: The statewide stilt population shows a stable or increasing trend at anumber greater than 2,000 birds for at least 5 consecutive years; and

Criterion 4: There are multiple self-sustaining breeding populations, includingpopulations on Kauaì/Niìhau, Oàhu, Hawaiì, and Maui/Molokaì/L~naì.

To consider delisting of the four species, the following criteria must be met:

Hawaiian Duck delisting criteria

Criterion 1: All core wetlands listed in Table 10 on the islands of Kauaì,Oàhu, Maui, and Hawaiì are protected and managed in accordance with themanagement practices outlined in this recovery plan;

Criterion 2: Of the supporting wetlands listed in Table 11 on the islands ofKauaì, Oàhu, Maui, and Hawaiì, 75 percent are protected and managed inaccordance with the management practices outlined in this recovery plan;

Criterion 3: The statewide Hawaiian duck population shows a stable orincreasing trend at a number greater than 2,000 birds for at least 10 consecutiveyears;


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Criterion 4: There are multiple self-sustaining breeding populations, withpopulations present on Kauaì, Oàhu, Maui, and Hawaiì; and

Criterion 5: The threat of hybridization with feral mallards is removed from allislands.

Hawaiian Coot delisting criteria



Criterion 3: The statewide coot population shows a stable or increasing trend ata number greater than 2,000 birds for at least 10 consecutive years; and

Criterion 4: There are multiple self-sustaining breeding populations, withpopulations present on Kauaì/Niìhau, Oàhu, Hawaiì, and Maui/Molokaì/L~naì.

Hawaiian Common Moorhen delisting criteria

Criterion 1: All core wetlands listed in Table 10 on the islands of Kauaì andOàhu are protected and managed in accordance with the management practicesoutlined in this recovery plan;

Criterion 2: Of the supporting wetlands listed in Table 11 on the islands ofKauaì and Oàhu, 75 percent are protected and managed in accordance with themanagement practices outlined in this recovery plan;

Criterion 3: The statewide moorhen population shows a stable or increasingtrend at a number greater than 2,000 birds for at least 10 consecutive years; and

Criterion 4: There are multiple self-sustaining breeding populations, withpopulations present on Kauaì, Oàhu, Hawaiì, and Maui/Molokaì.


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Hawaiian Stilt delisting criteria



Criterion 3: The statewide stilt population shows a stable or increasing trend at anumber greater than 2,000 birds for at least 10 consecutive years; and

Criterion 4: There are multiple self-sustaining breeding populations, withpopulations present on Kauaì/Niìhau, Oàhu, Hawaiì, and Maui/Molokaì/L~naì.

Recovery Actions Needed: 1) Protect and manage core and supporting wetland habitats in order to maximize

productivity and survival of endangered waterbirds. This would include thefollowing actions: develop written management plans; secure water sources; managewater levels; manage vegetation; control predation; monitor waterbird populationsand reproductive success; remove the threat of mallard-Hawaiian duckhybridization; minimize human disturbance; and monitor and control avian diseasesand environmental contaminants (Tables 10 and 11). Some of these wetland habitatareas already have protected status but need to be more actively managed.

2) Conduct research to better understand factors limiting Hawaiian waterbirdpopulation numbers, refine recovery objectives, and improve managementtechniques.

3) Establish a Hawaiian duck population on one additional island and moorhenpopulations on two additional islands.

4) Plan and implement an education program to increase landowner and land managerknowledge of waterbird needs and increase public support for waterbird recovery.

5) Reevaluate recovery objectives as additional information becomes available.


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Date of Recovery: Downlisting to threatened status could be initiated in 2010 anddelisting could be initiated in 2015, if recovery criteria are met.

Total Cost of Recovery: The total estimated cost to implement all recovery actionsfor all four species as described in the Recovery Actions Narrative over the next 10 yearsis $18,059,000 This figure may be substantially reduced with the development of moreeffective methods to address threats such as predator control. Certain costs, such as forsome research actions, have yet to be determined. The estimated costs for the first 5years of recovery implementation is $11,369,000; a detailed breakdown of these costs isprovided in the Implementation Schedule.

In addition to benefitting the four species of waterbirds addressed in this plan, therecovery actions described are also likely to aid in the recovery of the endangered Laysanduck (Anas laysanensis) and n‘n‘ or Hawaiian goose (Branta sandvicensis). Fossilrecords indicate that the Laysan duck was formerly found throughout the main HawaiianIslands, but it is currently restricted to the island of Laysan in the Northwestern HawaiianIslands. Management of wetlands in the main islands, particularly control of introducedpredators, could make them potentially suitable sites for reintroduction of Laysan ducks. Similarly, n‘n‘ are currently found primarily in upland areas on most islands, but theyhave been reestablished in low elevation wetlands at Hanalei National Wildlife Refuge onKauaì. Management and control of predators could provide suitable sites forreintroduction of n‘n‘ into other low elevation wetlands, where they can forage on thelush vegetation.


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Table of Contents

Executive Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . iii

I. Introduction and Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1A. INTRODUCTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1B. SPECIES ACCOUNTS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3

1. Hawaiian Duck or Koloa Maoli . . . . . . . . . . . . . . . . . . . . . . . . 3(a) Taxonomy. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3(b) Species Description. . . . . . . . . . . . . . . . . . . . . . . . . . . 3(c) Historical Range and Population Status. . . . . . . . . . . . 4(d) Current Range and Population Status . . . . . . . . . . . . . 5

i. Kauaì Population . . . . . . . . . . . . . . . . . . . . . . . 6ii. Oàhu Population . . . . . . . . . . . . . . . . . . . . . . . . 6iii. Maui Population . . . . . . . . . . . . . . . . . . . . . . . . 9iv. Hawaiì Population . . . . . . . . . . . . . . . . . . . . . . 9

(e) Life History . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9(f) Habitat Description . . . . . . . . . . . . . . . . . . . . . . . . . . 10(g) Species-specific Threats . . . . . . . . . . . . . . . . . . . . . . . 11

2. Hawaiian Coot or Àlae Keòkeò . . . . . . . . . . . . . . . . . . . . . 11(a) Taxonomy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11(b) Species Description . . . . . . . . . . . . . . . . . . . . . . . . . . 11(c) Historical Range and Population Status . . . . . . . . . . 12(d) Current Range and Population Status . . . . . . . . . . . . 12

i. Kauaì and Niìhau Populations . . . . . . . . . . . . 15ii. Oàhu Population . . . . . . . . . . . . . . . . . . . . . . . 15iii. Maui, Molokaì, and L~naì (Maui Nui)

Populations . . . . . . . . . . . . . . . . . . . . . . . . 15iv. Hawaiì Population . . . . . . . . . . . . . . . . . . . . . 16

(e) Life History . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16(f) Habitat Description . . . . . . . . . . . . . . . . . . . . . . . . . . 17

3. Hawaiian Common Moorhen or <Alae <Ula . . . . . . . . . . . . . . 18(a) Taxonomy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18(b) Species Description . . . . . . . . . . . . . . . . . . . . . . . . . . 18(c) Historical Range and Population Status . . . . . . . . . . 19


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(d) Current Range and Population Status . . . . . . . . . . . . 19i. Kauaì Population . . . . . . . . . . . . . . . . . . . . . . . 22ii. Oàhu Population . . . . . . . . . . . . . . . . . . . . . . . 22iii. Maui and Molokaì Populations . . . . . . . . . . . 22iv. Hawaiì Population . . . . . . . . . . . . . . . . . . . . . 22

(e) Life History . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22(f) Habitat Description . . . . . . . . . . . . . . . . . . . . . . . . . . 24

4. Hawaiian Stilt or Aeò . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24(a) Taxonomy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24(b) Species Description . . . . . . . . . . . . . . . . . . . . . . . . . . 24(c) Historical Range and Population Status . . . . . . . . . . 25(d) Current Range and Population Status . . . . . . . . . . . . 25

i. Kauaì and Niìhau Populations . . . . . . . . . . . . 28ii. Oàhu Population . . . . . . . . . . . . . . . . . . . . . . . 28iii. Maui, Molokaì, and L~naì (Maui Nui)

Populations . . . . . . . . . . . . . . . . . . . . . . . . 29iv. Hawaiì Population . . . . . . . . . . . . . . . . . . . . . 29

(e) Life History . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30 (f) Habitat Description . . . . . . . . . . . . . . . . . . . . . . . . . . 31

D. REASONS FOR DECLINE AND CURRENT THREATS . . . . . . . 441. Loss of Wetland Habitat . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 452. Hunting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 463. Predators . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 464. Alteration of Hydrology . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 475. Invasion of Habitat by Nonnative Plants . . . . . . . . . . . . . . . . 476. Hybridization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 487. Avian Disease . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 488. Environmental Contaminants . . . . . . . . . . . . . . . . . . . . . . . . . 58

E. CONSERVATION MEASURES . . . . . . . . . . . . . . . . . . . . . . . . . . . . 581. Federal and State Actions . . . . . . . . . . . . . . . . . . . . . . . . . . . 582. Private Actions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 623. Partnerships . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 62

F. MONITORING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63

II. Recovery . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65A. RECOVERY STRATEGY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65B. GOAL AND OBJECTIVES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71


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C. RECOVERY CRITERIA . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 72 1. Downlisting Criteria . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 73

(a) Hawaiian Duck downlisting criteria . . . . . . . . . . . . . 73(b) Hawaiian Coot downlisting criteria . . . . . . . . . . . . . 73(c) Hawaiian Common Moorhen downlisting criteria . . 73(d) Hawaiian Stilt downlisting criteria . . . . . . . . . . . . . . 74

2. Delisting Criteria . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 74(a) Hawaiian Duck delisting criteria . . . . . . . . . . . . . . . . 74(b) Hawaiian Coot delisting criteria . . . . . . . . . . . . . . . . 75(c) Hawaiian Common Moorhen delisting criteria . . . . . 75(d) Hawaiian Stilt delisting criteria . . . . . . . . . . . . . . . . . 75

D. STEP-DOWN OUTLINE OF RECOVERY ACTIONS . . . . . . . . . . 76E. NARRATIVE OUTLINE OF RECOVERY ACTIONS . . . . . . . . . . 79

III. Implementation Schedule . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 99A. ACTION PRIORITIES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 99B. ACTION NUMBER AND DESCRIPTION . . . . . . . . . . . . . . . . 99C. LISTING/DELISTING FACTORS . . . . . . . . . . . . . . . . . . . . . . . 99D. RESPONSIBLE PARTIES . . . . . . . . . . . . . . . . . . . . . . . . . . . . 100E. ACTION DURATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 100F. COST ESTIMATES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 101G. ACRONYMS USED . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 101

IV. References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 117A. LITERATURE CITED . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 117B. PERSONAL COMMUNICATIONS . . . . . . . . . . . . . . . . . . . . . . . . 125

V. Appendices . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 127APPENDIX A. Core Wetlands . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 127APPENDIX B. Supporting Wetlands . . . . . . . . . . . . . . . . . . . . . . . . . . 131APPENDIX C. Comprehensive List of Wetlands. . . . . . . . . . . . . . . . . 138APPENDIX D. Endangered and Threatened Species Recovery Priority

Number Guidelines . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 150APPENDIX E. Hawaii Waterbird Count Instructions . . . . . . . . . . . . . 151


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List of Figures

Figure 1. Map of the main Hawaiian Islands . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2

Figure 2. Hawaiian duck female and male. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4

Figure 3. Hawaiian duck winter counts, based on biannual waterbird counts from1996 to 2002 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

Figure 4. Hawaiian duck summer counts, based on biannual waterbird countsfrom 1996 to 2002. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8

Figure 5-A. Color variation in frontal shield and bills of Hawaiian coots. . . . . 11

Figure 5-B. Hawaiian coot. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12

Figure 6. Hawaiian coot winter counts, based on biannual counts from 1976 to2003. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13

Figure 7. Hawaiian coot summer counts, based on biannual counts from 1976 to2002. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14

Figure 8. Hawaiian common moorhen. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19

Figure 9. Hawaiian common moorhen winter counts, based on biannualwaterbird counts from 1977 to 2002. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20

Figure 10. Hawaiian common moorhen summer counts, based on biannualwaterbird counts from 1977 to 2002. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21

Figure 11-A. Adult male Hawaiian stilt. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25

Figure 11-B. Juvenile Hawaiian stilt. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25

Figure 12. Hawaiian stilt winter counts, based on biannual waterbird counts from1976 to 2003. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26

Figure 13. Hawaiian stilt summer counts, based on biannual waterbird countsfrom 1976 to 2002. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27

Figure 14. Waterbird populations at wetlands on Oàhu. . . . . . . . . . . . . . . . . . . 33

Figure 15. Waterbird populations at wetlands on Maui. . . . . . . . . . . . . . . . . . . . 34

Figure 16. Waterbird populations at wetlands on Molokaì and Lanaì. . . . . . . 35


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Figure 17. Waterbird populations at wetlands on Kauaì and Niìhau. . . . . . . 36

Figure 18. Waterbird populations at wetlands on Hawaiì. . . . . . . . . . . . . . . . . 43

Figure 19. Distribution and abundance of Hawaiian ducks, feral mallards, andmallard-Hawaiian duck hybrids on Oàhu, based on winter counts from1999 to 2003. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50

Figure 20. Distribution and abundance of Hawaiian duck, feral mallards, andmallard-Hawaiian duck hybrids on Maui, based on winter counts from1999 to 2003. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51

Figure 21. Distribution and abundance of Hawaiian duck, feral mallards, andmallard-Hawaiian duck hybrids on Hawaiì, based on winter counts from1999 to 2003. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52

Figure 22. Distribution and abundance of Hawaiian ducks, feral mallards, andmallard-Hawaiian duck hybrids on Kauaì, based on winter counts from1999 to 2003. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53

Figure 23. Mallard-Hawaiian duck hybrid winter and summer counts on Oàhu,based on biannual waterbird counts from 1986 to 2002. . . . . . . . . . . . . . 54

Figure 24. Mallard-Hawaiian duck hybrid winter and summer counts on Maui,based on biannual waterbird counts from 1999 to 2003. . . . . . . . . . . . . . 55

Figure 25. Mallard-Hawaiian duck hybrid winter and summer counts on Hawaiì,based on biannual waterbird counts from 1986 to 2002. . . . . . . . . . . . . . 56

Figure 26. Mallard-Hawaiian duck hybrid winter and summer counts on Kauaì,based on biannual waterbird counts from 1986 to 2003. . . . . . . . . . . . . . 57


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List of Tables

Table 1. Locations of numbered wetlands on Oàhu shown in Figure 14. . . . . . 34

Table 2. Locations of numbered wetlands on Maui shown in Figure 15. . . . . . . 37

Table 3. Locations of numbered wetlands on Molokaì (Mo) and L~naì (L)shown in Figure 16. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38

Table 4. Locations of numbered wetlands on Kauaì (K) and Niìhau (N) shownin Figure 17. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41

Table 5. Locations of numbered wetlands on Hawaiì shown in Figure 18. . . . 44

Table 6. Core and supporting wetlands on Kauaì (K) and Niìhau (N) identifiedfor protection and management in order to recover the Hawaiian duck,Hawaiian coot, Hawaiian common moorhen, and Hawaiian stilt. . . . 67

Table 7. Core and supporting wetlands on Oàhu identified for protection andmanagement in order to recover the Hawaiian duck, Hawaiian coot,Hawaiian common moorhen, and Hawaiian stilt. . . . . . . . . . . . . . . . . . . 68

Table 8. Core and supporting wetlands on Maui (M), Molokaì (Mo), and L~naì(L) identified for protection and management in order to recover theHawaiian duck, Hawaiian coot, Hawaiian common moorhen, andHawaiian stilt. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69

Table 9. Core and supporting wetlands on Hawaiì island identified for protectionand management in order to recover the Hawaiian duck, Hawaiian coot,Hawaiian common moorhen, and Hawaiian stilt. . . . . . . . . . . . . . . . . . . 70

Table 10. Specific recovery actions recommended for core wetlands in the mainHawaiian Islands. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 93

Table 11. Specific recovery actions recommended for supporting wetlands in themain Hawaiian Islands. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 95


1

I. Introduction and Overview

A. INTRODUCTION

Hawaiì accounts for less than 1percent of the total land mass of theUnited States, yet it is home toapproximately 40 percent of all animaland plant species federally listed asthreatened or endangered (U.S. Fish andWildlife Service [USFWS] 2004a). Atotal of 109 endemic (i.e., found only inHawaiì) species and subspecies of birdshave been described in the HawaiianIslands, 35 (32 percent) of which arestill extant (Scott et al. 2001). Reasonsfor losses of many of the Hawaiian birdshave been well documented, includingdestruction and alteration of habitat,hunting, introduced predatory mammalsand nonnative birds, and diseases(Warner 1968; Atkinson 1977; vanRiper et al. 1986; Cuddihy and Stone1990; Engilis and Pratt 1993; Scott et al.2001).

The Hawaiian Islands historicallysupported a diverse array of waterbirdsin both wetland and forest habitats. Atleast 30 waterbird species are knownfrom historical and fossil records (Scottet al. 2001). During the past 2,000years of human presence, all ofHawaiì’s endemic rails, flightlessgeese, and an ibis have become extinct(Olson and James 1991). This massiveextinction is attributed to the impacts ofhumans and the plants and animals theyintroduced to Hawaiì. Both Polynesianand European settlers have played

significant roles in the alteration ofHawaiian ecosystems and the resultingextinctions of species (Kirch 1982,1983; Olson and James 1992).

The six endemic species ofwaterbirds that persist today are theHawaiian duck or koloa maoli (Anaswyvilliana), Laysan duck (A.laysanensis), Hawaiian coot or àlaekeòkeò (Fulica alai), Hawaiiancommon moorhen or àlae ùla(Gallinula chloropus sandvicensis),Hawaiian stilt or aeò (Himantopusmexicanus knudseni), and the Hawaiiangoose or n‘n‘ (Branta sandvicensis). All of these species, with the exceptionof n‘n‘, require wetlands for theirsurvival, and all are listed asendangered. Recovery actions for theLaysan duck and the n‘n‘ are outlinedin separate recovery plans (USFWS2004b,c). In this document, unlessotherwise noted, the term “endangeredwaterbirds” refers to the four speciesaddressed by this plan: the Hawaiianduck, Hawaiian coot, Hawaiian commonmoorhen, and Hawaiian stilt. Thesefour species are currently found onvarious "main Hawaiian Islands" (Figure1). The term "main Hawaiian Islands"refers to the following eight islands: Niìhau, Kauaì, Oàhu, Maui, Molokaì,L~naì, Kahoòlawe, and Hawaiì (alsoknown as "the Big Island"). The islandsof Maui, Molokaì, and L~naìcollectively comprise “Maui Nui.”

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The Hawaiian duck and Hawaiiancommon moorhen were added to theFederal List of Endangered andThreatened Plants in 1967 (USFWS1967), and the Hawaiian coot and stiltwere added to this list in 1970 (USFWS1970a). Recovery priority numbersranging from 1C to 18 (1C being highestpriority) are assigned to each listedspecies based on degree of threat,recovery potential, taxonomic status,and conflict with human activities(USFWS 1983a,b; Appendix D). Recovery priority numbers with a letterdesignation of “C” indicate conflict withhuman economic activity. The recoverypriority number of 2 for the Hawaiianduck reflects a high degree of threat, ahigh potential for recovery, and itstaxonomic status as a full species, whichis given a higher priority than asubspecies. The Hawaiian commonmoorhen and Hawaiian stilt each have arecovery priority number of 9, reflectinga moderate degree of threat, a highpotential for recovery, and theirtaxonomic status as subspecies. Therecovery priority number of 14 for theHawaiian coot reflects a low degree ofthreat, a high potential for recovery, andits taxonomic status as a distinct species. The Hawaiian coot was considered asubspecies of the American coot (Fulicaamericana) at the time it was listed, butit was recently split from the Americancoot and is now regarded as a distinctspecies (Fulica alai; AmericanOrnithologists’ Union [AOU] 1989). Critical habitat has not been designatedfor any of these species.

B. SPECIES ACCOUNTS

1. Hawaiian Duck or KoloaMaoli

(a) Taxonomy. The Hawaiianduck or koloa maoli (Anas wyvilliana)was first described in 1851. At the time,it was considered to be a species orpossibly a subspecies of the mallard(Anas platyrhynchos). However, morerecent genetic studies indicate that theHawaiian duck is distinct at the specieslevel and is closely related to themallard (AOU 1983; Browne et al.1993). Allozyme data indicate there hasbeen extensive hybridization betweenHawaiian ducks and feral mallards onOàhu, with the near disappearance ofHawaiian duck alleles from thepopulation on that island (Browne et al.1993). On Maui, Kauaì, and Hawaiì,Hawaiian duck-mallard hybrids havebeen documented but occur inapparently low numbers (Engilis et al.2002; Hawaiì Department of Land andNatural Resources [HDLNR] 1976-2003).

(b) Species Description. TheHawaiian duck is a small (mean weightof males 604 grams [19 ounces],females 460 grams [15 ounces]), drab-brown duck (Griffin and Browne 1990).Both sexes are mottled brown andsimilar in appearance to a femalemallard (Figure 2). Adult males aredark brown, variably spotted andmottled, with distinctive dark brownchevrons on the breast, flank, and back


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Figure 2. Hawaiian duck female (front) and male. USFWS file photo.

feathers, and an olive bill (Engilis et al.2002). Adult females are similar but areslightly smaller than males on average,and slightly lighter in color, withplainer, buff-colored chin and backfeathers (Engilis et al. 2002). Bothsexes have emerald green to bluespeculums (brightly colored areas on thewings), bordered both in front and backby white, with orange to yellow-orangelegs and feet. The plumage of first-yearmale Hawaiian ducks resembles theeclipse (non-breeding) plumage of malemallards, with a subdued green head andblack upper and under-tail coverts (theshort feathers covering the base of thetail feathers).

In areas where hybridization occurswith mallards, it may be difficult todistinguish between Hawaiian ducks,female mallards, and hybrids. Hawaiianducks and mallards differ in size,behavior, voice, and coloration. Theextent of the differences between thesetwo species and hybrids is dependentupon the extent of hybridization at thelocation, the plumage at that time of

year, and variation among individualsand islands, making it difficult todistinguish Hawaiian ducks and hybridsbased on phenotypic (visible)characteristics alone. Research thatcombines morphological measurementsand genetic identification, partly fundedby the U.S. Fish and Wildlife Service, iscurrently being conducted in order todevelop reliable criteria fordistinguishing between Hawaiian ducks,female mallards, and hybrids (A.Engilis, Ducks Unlimited [formerly],pers. comm. 2003). Hawaiian ducklingscan be distinguished from mallardducklings more easily than adults. Hawaiian ducklings are primarily darkbrown with a yellow mark on the chin,and do not have a yellow eyestripe orflank spot as do mallard ducklings (F.Duvall, Hawaiì Division of Forestryand Wildlife, pers. comm. 2004).

(c) Historical Range andPopulation Status. Hawaiian duckswere known historically from all of themain Hawaiian Islands except L~naìand Kahoòlawe. There are nopopulation estimates prior to 1940, butin the 1800's they were fairly commonin natural and farmed wetland habitats(Engilis et al. 2002). The arrival of thePolynesian people in Hawaiì about1,600 years ago (Kirch 1982) and theircultivation of taro (Colocasiaesculenta), an agricultural crop grown ina pond-like environment, considerablyincreased the amount of wetland habitatin the islands (Swedberg 1967). Rice(Oryza sativa) cultivation from the late1800's to the 1940's continued to


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provide wetland habitat for theHawaiian duck. A decline in floodedagriculture had occurred by 1900, butthere were still about 7,700 hectares(19,000 acres) of taro and 6,500 hectares(16,000 acres) of rice at that time(Bostwick 1982).

A variety of factors, includingpredation of eggs and chicks by rats(Rattus spp.), mongooses (Herpestesauropunctatus), domestic dogs (Canisfamiliaris), domestic cats (Felis catus),introduced fish and birds, habitatreduction due to changes in agriculturalpractices and urban development, andlocal hunting pressure, brought about asignificant population decline of theHawaiian duck early in the 20th century. Introduced ungulates such as pigs (Susscrofa) and goats (Capra hircus) havesignificantly impacted Hawaiian ducknesting habitat along Kauai's montanestreams (T. Telfer, Hawaiì Division ofForestry and Wildlife, and A. Engilis,Ducks Unlimited, pers. comm. 1992). In 1949, an estimated 500 Hawaiianducks remained on Kauaì, and about 30on Oàhu. By that time, Hawaiian duckswere considered only an occasionalvisitor to the island of Hawaiì, andwere presumed extirpated on Maui andMolokaì (Schwartz and Schwartz1949). By 1960, they were apparentlyextirpated on Oàhu when KaelepuluPond in Kailua, the last Hawaiian duckstronghold on Oàhu, was modified aspart of a housing development. By the1960's, Hawaiian ducks were found insmall numbers only on Kauaì andprobably on Niìhau.

From the late 1950's through theearly 1990's, Hawaiian ducks werereintroduced to Oàhu, Maui, andHawaiì (Paton 1981; Bostwick 1982;Engilis et al. 2002) through captivepropagation and release (see Federal andState Actions under Section E,Conservation Measures, for details). Although populations of Hawaiianducks still exist on each of these islands,these populations are impacted byhybridization with feral mallards tovarying degrees.

(d) Current Range andPopulation Status. Engilis et al.(2002) estimated the current statewidepopulation of pure Hawaiian ducks to be2,200 birds, with 2,000 on Kauaì and200 on Hawaiì. The biannual waterbirdcount1 produces a lower number, anaverage of 337 based on winter countsfrom 1998 through 2003, primarilybecause this survey does not includemontane streams that harbor much ofthe Hawaiian duck population on Kauaìand Hawaiì. In addition, approximately300 and 50 Hawaiian duck-like birdsoccur on Oàhu and Maui, respectively,some of which may be Hawaiian ducks,with the remainder being mallard-Hawaiian duck hybrids. The totalHawaiian duck population appears to beincreasing based on the biannualwaterbird count, due primarily toincreases in the Hawaiian duckpopulation on Kauaì, but Hawaiian

1See Section F. Monitoring (p. 63),for a description of the biannual waterbirdcounts.


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ducks are declining on other islands(Figures 3 and 4) due to hybridization(Engilis and Pratt 1993; see Figures 23–25, pages 54–56). On Kauaì, seasonalmovement of birds occurs from lowlandwetlands to more secluded habitats insummer. Differences between thesummer and winter bird surveys couldrepresent altitudinal movements,dispersal up stream valleys, or possiblya reclusive post-breeding molt period.

i. Kauaì Population. TheHawaiian duck population on Kauaì hasmaintained itself without the release ofcaptive-bred birds. Lowland surveysduring the 1940's and 1950's estimatedthe population at 500 birds. Surveys inthe 1960's estimated a population of3,000 Hawaiian ducks (Swedberg 1967),mostly in remote montane streams andvalleys. This apparent increase wasprobably a result of the underestimationof birds in the mountainous streamhabitat by earlier observers. The islandpopulation was estimated to be between1,500 and 2,000 Hawaiian ducks in1988 (T. Telfer, pers. comm. 1988). The most recent estimate placed theKauaì population at 2,000 birds(Engilis et al. 2002). The Hawaiianduck population on Kauaì issubstantially larger than on all otherislands combined. This comparativelylarge population size is probably due tothe lack of an established population ofmongooses and very low occurrence ofhybridization. However, the threat ofhybridization with mallards and itspotential to increase on Kauaì is of

great concern, and mongooses havebeen detected recently on Kauaì.

Many Hawaiian ducks on Kauaìuse lowland ponds and wetlandsprimarily for feeding and loafing, andnest along montane streams. Hawaiianducks use the Hanalei National WildlifeRefuge and nearby taro fieldsthroughout the year. They feedprimarily in the taro loì (ponds), with asmall number of ducks breeding in thearea. Numbers of Hawaiian ducksincreased at the refuge with the creationof impoundments in the 1980's and1990's, which initially providedadditional loafing areas. Modificationsto the impoundments in 1999 providedadditional foraging habitat. Manmadereservoirs, particularly near L§huè andon the M~n~ Plain, are also used byHawaiian ducks.

ii. Oàhu Population. Hawaiianducks were reintroduced to Oàhuthrough a captive propagation andrelease program between 1958 and1982. During this period, a total of 326Hawaiian ducks were released by Statebiologists at Kawainui Marsh (177birds), Nuùpia Ponds (45), WaimeaFalls Park (66), and Hoòmaluhia Cityand County Park (38). However, thestatus of Hawaiian ducks on Oàhu isquestionable due to the abundance of mallard-Hawaiian duck hybrids. Agenetic study by Browne et al. (1993)found that all birds sampled on Oàhuwere hybrids, although the sample ofbirds tested was small. Biannual

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N ote : In 1982,1994,1996, and 2002, not a ll rou tinely surveyed is land wetlands on a particu lar is land were covered during sum m er surveys. C ounts on the fo llow ing is lands and years m ay be erroneously low :1982 - O ’ahu1984, 1996 – Hawai’i2002 – Kaua’i and Hawai’i

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waterbird surveys indicate a decreasingpopulation trend over the past 5 yearsfor the Hawaiian duck on Oàhu(Figures 3 and 4), while the number ofmallard-Hawaiian duck hybrids hasincreased (Figure 23, page 54). Hawaiian ducks are still reported fromwetlands on the windward coast ofOàhu (Kawainui, H~m~kua, and HeèiaMarshes, Kaèlepulu and NuùpiaPonds, and Hoòmaluhia BotanicalGarden), north shore (James CampbellNational Wildlife Refuge, Kahukuaquaculture ponds, Punahoòlapa,Haleìwa), Pearl Harbor area (PearlHarbor National Wildlife Refuge,Pouhala Marsh), and Lualualei (Figure19, page 50), but whether these areHawaiian ducks or hybrids is not clear.

iii. Maui Population. A release offewer than 12 captive-bred Hawaiianducks was conducted on Maui by theState of Hawaiì in 1989. From thesebirds, a small breeding population wasestablished (F. Duvall, pers. comm.2004). Currently, the Hawaiian duckpopulation probably numbers fewer than20 birds, which occur primarily atKanah~ Pond (Figure 15, page 36). Mallards were not eradicated from Mauiprior to the release of Hawaiian ducks,and hybridization is now occurring. Biannual waterbird counts over the past5 years indicate hybrids may outnumberHawaiian ducks (HDLNR 1976-2003;Figures 20 and 24, pages 51 and 55).

iv. Hawaiì Population. Thenumber of Hawaiian ducks on Hawaiìwas estimated to be 200 by Engilis et al.

(2002). The number of Hawaiian duckscounted on the biannual waterbirdsurveys is much lower (Figures 21 and25, pages 52 and 56), but these surveysdo not include montane stream habitat inKohala where many ducks occur. Hawaiian ducks were reestablished onthe island of Hawaiì between 1976 and1982, when captive-bred birds werereleased in the Kohala Mountains. Some birds have dispersed from releasesites and have been recorded up to 32kilometers (20 miles) away (Giffin1982). They have been observed usingstock ponds in the Kohala Mountains,stream habitats of Pololã, Waimanu, andWaipio Valleys, and on Mauna Kea instock ponds and larger montane streams. Successful breeding in the wild has beendocumented in the Kohala Mountainsand at Hakalau Forest National WildlifeRefuge. Hawaiì’s upper elevationHawaiian duck population was thoughtto be genetically pure and isolated fromlowland populations of mallards, butpair bonds between Hawaiian ducks andmallards have been observed in the Hiloarea (Engilis et al. 2002), and morerecently hybrid birds have beendocumented to occur on Hawaiì’slowland wetlands (Figure 21, page 52;A. Engilis, pers. comm. 2003).

(e) Life History. Hawaiian ducksbreed year-round, but the majority ofnesting records are from March throughJune (Engilis et al. 2002). In Kauaìlowlands, Hawaiian ducks form pairbonds between November and May,with pairs dispersing to montane nestinglocalities. Hawaiian duck numbers


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fluctuate seasonally at Hanalei NationalWildlife Refuge, with the highestnumbers in September and lowestnumbers in June and July (A. Asquith,Hanalei National Wildlife Refuge, pers.comm. 1999). These seasonal changesmay reflect dispersal into montane areasduring the breeding season, perhapsindicating a later breeding period forthese Kauaì birds. Some pairs findsuitable nesting habitat in lowlandwetlands.

Nests are on the ground near water,but little else is known of their specificnesting habits. There have been fewdocumented records of nesting in areaspopulated by humans, particularly wherecats, dogs, or mongooses are common. Clutch size ranges from 2 to 10 eggs(mean = 8.3) (Swedberg 1967). Incubation lasts approximately 30 days,with most chicks hatching from April toJune.

Hawaiian ducks are usually foundalone or in pairs and are wary,particularly when nesting or molting. Hawaiian ducks may congregate insubstantially larger numbers whenloafing or exploiting rich food sources. Concentrations of 200 or more Hawaiianducks have been observed at HanaleiNational Wildlife Refuge. They arestrong flyers and usually fly at lowaltitudes. Hawaiian ducks exhibit intra-island movement but dispersaltendencies are still unclear (Engilis et al.2002).

Hawaiian ducks, like mallards,apparently are opportunistic feeders. Foods consumed include snails, insectlarvae, earthworms, grass seeds, rice,green algae, and seeds and leaf parts ofwetland plants (Swedberg 1967). Feeding in wetlands and streamstypically occurs in water less than 24centimeters (9.4 inches) deep (Engilis etal. 2002).

(f) Habitat Description. TheHawaiian duck historically used a widevariety of natural wetland habitats fornesting and feeding, includingfreshwater marshes, flooded grasslands,coastal ponds, streams, montane pools,and forest swamplands at elevationsranging from sea level to 3,000 meters(9,900 feet). Agricultural and artificialwetlands such as taro, lotus (Nelumbonucifera), shrimp, fish, and sewagetreatment ponds supplement naturalwetland habitats and provide importantfeeding habitat for the Hawaiian duck. They may also use irrigation ditches,flooded ephemeral fields, reservoirs, andthe mouths of larger streams for feedingor nesting.

Swedberg (1967) estimated that 90percent of the Hawaiian duck populationon Kauaì lives along that island'sextensive upland stream system,between 300 and 1,200 meters (1,000 to4,000 feet) elevation. A typical streamused by the Hawaiian duck on the BigIsland is 7 meters (23 feet) wide, swiftlyflowing, strewn with boulders, and hasheavily vegetated banks (Paton 1981). However, little information is available


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Figure 5-A. Color variation in frontal shields and bills of Hawaiian coots. Photo by Eric VanderWerf.

on habitat use of upland stream systemsby the Hawaiian duck.

Ephemeral wetlands are importanthabitat for the Hawaiian duck, althoughhow they are used beyond foraging isunknown (Engilis et al. 2002). Hawaiian ducks move regularly betweenNiìhau and Kauaì in response toabove-normal precipitation and theflooding and drying of Niìhau’sephemeral wetlands (Engilis 1988;Engilis and Pratt 1993). Moreinformation is needed on movements ofthe Hawaiian duck in response to theavailability of seasonal and permanentwetland habitats between the summer(dry) and winter (wet) seasons.

(g) Species-specific Threats.Hybridization with feral mallards iscurrently the primary threat to therecovery of the Hawaiian duck. Extensive hybridization has occurred onOàhu and Maui, with limitedhybridization on Kauaì and Hawaiì. Hybridization is unlikely to occur withwild migratory mallards that winter orpass through the islands since migrantsoccur in Hawaiì during their non-

breeding season. Damage to watershedsby pigs, goats, and other feral ungulatesmay pose direct impacts to nestinghabitat. Other limiting factors thatthreaten all of Hawaiì’s waterbirds arecovered in the “Reasons for Decline andCurrent Threats” section of this recoveryplan.

2. Hawaiian Coot or ÀlaeKeòkeò

(a) Taxonomy. The Hawaiiancoot or àlae keòkeò (Fulica alai) isendemic to the Hawaiian Islands. In thepast the Hawaiian coot was considered asubspecies of the American coot (Fulicaamericana) and was originally listedunder the Endangered Species Act assuch, but it is now regarded as a distinctspecies (AOU 1993). The Hawaiiancoot is nonmigratory and presumablyoriginated from stray migrants fromcontinental North America thatremained as residents in the islands(Brisbin et al. 2002).

(b) Species Description. TheHawaiian coot is smaller in body sizethan the American coot, and the bulbous

frontal shield above the bill isdistinctly larger than that of theAmerican coot and is usuallycompletely white (Shallenberger1977; Pratt et al. 1987. A smallpercentage of the Hawaiian cootpopulation has a red lobe at thetop of the frontal shield and deepmaroon markings at the tip of thebill, similar to the American coot(Pratt et al. 1987; Figure 5-A).


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Figure 5-B. Hawaiian coot. Photo by Eric VanderWerf.

Adult coots are dark, slate-gray in color,with white undertail feathers. Male andfemale coots are similar in color. Cootshave large feet with lobed toes, unlikethe webbed feet of ducks (Figure 5-B). Immature coots are a lighter gray withbuff-tipped contour feathers, smaller,dull white bills, and lack a well-developed frontal shield. Downy chickshave red skin and a bill with a yellowtip, similar to that of the American coot(Brisbin et al. 2002).

(c) Historical Range andPopulation Status. Hawaiian cootshistorically occurred on all of the mainHawaiian Islands except L~naì andKahoòlawe, which lacked suitablewetland habitat. Coots have alwaysbeen most numerous on Oàhu, Maui,and Kauaì (Shallenberger 1977). It islikely that they were once fairlycommon in large natural marshes andponds and used wetland habitats createdby Hawaiians for taro cultivation andlarge scale fish production.

No population estimates areavailable prior to the 1950's, howeverSchwartz and Schwartz (1949)identified a decline and potential threatof extinction in the first half of thiscentury. Censuses from the late 1950'sto the late 1960's indicated a populationof fewer than 1,000 birds, contributingto the Federal listing of the Hawaiiancoot as endangered (USFWS 1978).

(d) Current Range andPopulation Status. Hawaiian cootscurrently inhabit all of the mainHawaiian Islands except Kahoòlawe. Based on winter counts from biannualwaterbird surveys from 1998 through2003 (2002 was excluded due to missingdata), the coot population averaged2,100 birds and fluctuated between1,500 and 3,000 birds (HDLNR 1976-2003). Summer counts were generallymore variable than winter counts due tothe variability in hatch-year birdsurvival. As coots are conspicuous andoften use open water areas, they arerelatively easy to census, so these dataare considered fairly accurate minimumpopulation estimates. Not all wetlandsare counted, but the population numbersat least 2,100 coots, with Kauaì, Oahu,and Maui supporting 80 percent of thesebirds. Engilis and Pratt (1993) reportedthe statewide coot population to rangefrom 2,000 to 4,000 birds.

Survey data from 1976 through2003 reveal short-term populationfluctuations, with a long-term slightlyincreasing population trend overall(Figures 6 and 7). Coots are known to

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Figure 6 . H awaiian coot w in ter counts, based on b iannua l counts from 1976 to 2003.

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Figure 7 . H awaiian coot sum m er counts, based on b iannual counts from 1976 to 2002.

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disperse readily and exploit seasonallyflooded wetlands, thus their populationswill naturally fluctuate according toclimatic and hydrologic conditions(Engilis and Pratt 1993). The largeplaya lakes on Niìhau have supportedlarge numbers of coots in wet years.

i. Kauaì and NiìhauPopulations. On Kauaì, coots occurprimarily in lowland valleys, such asHanalei, Lumahaì, and `Æpaekaà, andin reservoirs, but they have occasionallybeen observed in plunge pools atelevations above 1,500 meters (4,950feet) (HDLNR 1989). Over the past 5 years (excluding 2002 due to missingdata), the coot population on Kauaì hasfluctuated between 300 and 1,500 birds(HDLNR 1976-2003). Some of thisvariation is due to dispersal of coots toNiìhau in wet years. Several authorshave speculated that annual migrationoccurs between Kauaì and Niìhau, butstatewide surveys indicate that thesemovements are less frequent, usuallyoccurring when annual precipitation isabove normal and Niìhau’s ephemerallakes become flooded (Engilis and Pratt1993). Numbers of coots counted onNiìhau during wet winters include 949birds in 1986 and 803 birds in 1996, butNiìhau has not been surveyed since1999.

ii. Oàhu Population. On Oàhu,the coot population has fluctuatedbetween approximately 500 and 1,000birds in recent years (HDLNR 1976-2003). Oàhu's extensive coastalwetlands provide excellent habitat for

Hawaiian coots, and the species occursless frequently on interior reservoirs,such as Lake Wilson and NuùanuReservoir. Large concentrations ofcoots occur at the Kiì Unit of JamesCampbell National Wildlife Refuge, theKahuku aquaculture ponds, the Kuilimawastewater treatment plant, KaèlepuluPond in Kailua, the Honouliuli Unit ofPearl Harbor National Wildlife Refuge,and the Hawaiì Prince Golf Course(Figure 14, page 33). Aquacultureponds for shrimp and fish productionprovide year-round foraging habitat forcoots; however, nesting opportunitiesare limited on these ponds as vegetationis generally controlled along the banksand predators (dogs, cats, andmongooses) can readily find nestsaround these ponds.

iii. Maui, Molokaì, and L~naì(Maui Nui) Populations. The cootpopulation on Maui Nui fluctuatesbetween approximately 200 to 600 birds(HDLNR 1976-2003). The largestconcentrations of coots occur at Kanah~and Ke~lia Ponds on Maui, theKaunakakai Sewage Treatment Pondson Molokaì, and the L~naì SewageTreatment ponds (Figures 15, 16 [pages36, 39]). Waterbird survey data suggestthat annual movements occur betweenKanah~ and Ke~lia Ponds, and alsopossibly among islands within MauiNui. Monthly surveys of Kanah~ andKe~lia Ponds from 1995 to 1999 suggestthat increased coot numbers at Ke~liaPond are the result of influxes fromother populations. This assumption issupported by counts at Ke~lia Pond


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which exceed the combined total ofKe~lia and Kanah~ Ponds from theprevious monthly count (M. Nishimoto,Maui National Wildlife RefugeComplex, pers. comm. 2004). Inaddition to these wetlands, many of theremaining reservoirs associated withformer sugar cane (Saccharumofficinarum) production are frequentedby coots.

The largest concentrations of cootson Molokaì occur at the KaunakakaiSewage Treatment Ponds and KualapuùReservoir, but coots also occur onMolokai's coastal ponds and playawetlands, particularly Paialoa Pond. There is some evidence from statewidewaterbird surveys that coots movebetween Maui and Molokaì. Thesemovements are not seasonal, but aresporadic and seem to correlate withperiods of heavy rainfall (Engilis andPratt 1993). The playa habitats onMolokaì are usually dry, but flood inwet winters. Coots have becomepermanent residents at the L~naì Citywastewater treatment ponds since 1989when these ponds became operational. During the 2002 summer waterbirdcounts, 45 birds were observed usingthis area. Coots have also beenobserved nesting at the wastewatertreatment facility (HDLNR 1976-2003).

iv. Hawaiì Population. The BigIsland, with its limited wetlands,supports only a small Hawaiian cootpopulation, generally fewer than 100birds (HDLNR 1976-2003). Four pondson the island support the majority of

these birds: Àimakap~ and `ÆpaeùlaPonds on the Kona Coast, and Waiakeaand Loko Waka Ponds in Hilo. Thelatter two ponds are in an urban area. The Big Island's coot population showslittle seasonal fluctuation. Numbersvary from year to year, suggesting birdsdisperse to and from other islands.

(e) Life History. Hawaiian cootsnest on open fresh water and brackishponds, taro ponds, shallow reservoirs,irrigation ditches, and in small openingsof marsh vegetation (Udvardy 1960; Shallenberger 1977). They constructfloating nests of aquatic vegetation inopen water, or semi-floating nestsanchored to emergent vegetation or inclumps of wetland vegetation (Byrd etal. 1985). Open-water nests typicallyare anchored on semi-floating mats ofvegetation, usually constructed fromwater hyssop (Bacopa monnieri) andHilo grass (Paspalum conjugatum). Nests in emergent vegetation areplatforms constructed from buoyantstems of nearby vegetation, such asbulrush (Scirpus spp.) (Byrd et al.1985). Nests have also beendocumented on shorelines or rocky islets(M. Morin, USFWS, pers. comm. 1994). Additional "false nests" may beconstructed near the actual nest and areoften used as loafing or broodingplatforms.

Nesting occurs primarily fromMarch through September, althoughsome nesting occurs in all months of theyear (Shallenberger 1977). Nestingoccurred at Àimakap~ Fishpond,


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Hawaiì, in all months except Novemberand January (M. Morin, pers. comm.1999). The timing of nesting appears tocorrespond with seasonal weatherconditions (Byrd et al. 1985; Engilis andPratt 1993). Water levels are critical fornest initiation and success. Taro pondsprovide good nesting habitat becausethey are shallow and have limited waterfluctuation compared to other sites. Clutch size ranges from 3 to 10 eggs,with an average of 5 eggs (Byrd et al.1985). The incubation period is about25 days (Shallenberger 1977; Bryd et al.1985), and chicks are able to swim assoon as their down has dried (Brisbin etal. 2002).

Coots are generalist feeders,obtaining food near the surface of thewater, diving, or foraging in mud orsand. They also graze on upland grassysites such as golf courses that areadjacent to wetlands, especially duringtimes of drought and when food isunavailable elsewhere (T. Telfer, pers.comm. 1999). Food items include seedsand leaves of aquatic plants, variousinvertebrates including snails,crustaceans, and aquatic or terrestrialinsects, tadpoles, and small fish(Schwartz and Schwartz 1949). Cootstypically feed close to their nesting areasbut will travel long distances when foodis not locally available (Shallenberger1977). Intra-island movements occurwhen water levels are low and foodsources become concentrated.

The Hawaiian coot is an active andat times gregarious species. Like its

North American relative, the Hawaiiancoot sometimes forms large flocks. Thisusually occurs in the summer, but somelocalities do not show a seasonalflocking pattern, such as the HanaleiNational Wildlife Refuge where largecoot flocks have been observed duringall months.

Coot population fluctuations may beexplained by inter-island dispersal inrelation to rainfall patterns and are notthe result of North American cootsmigrating to the Hawaiian Islands(Engilis and Pratt 1993). Statewidewaterbird surveys from 1977 to 1986indicate that coots migrate betweenislands in response to precipitationpatterns. Periodic increases in cootnumbers on Niìhau and Molokaìpresumably are the result of movementof birds from Kauaì and Maui,respectively (Engilis and Pratt 1993). Population increases on Niìhau arecorrelated with the intermittentavailability of wetlands resulting fromhigh rainfall.

(f) Habitat Description. TheHawaiian coot is typically a species ofthe coastal plain, usually found below400 meters (1,320 feet) elevation, andpreferring wetland habitats with suitableemergent plant growth interspersed withopen water. However, some birds useupland plunge pools above 1,500 meters(4,900 feet) on Kauaì and montanestock ponds up to 2,000 meters (6,600feet) on Hawaiì. Hawaiian coots preferfreshwater wetlands, but will usebrackish wetlands, and rarely, saline


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habitats. Coots forage in water less than30 centimeters (12 inches) deep, but candive in water up to 120 centimeters (48inches) deep. They prefer more openwater than do moorhens, particularly forfeeding. Optimum nesting habitat forthe North American coot (Fulicaamericana) is generally in a 50:50 to75:25 mix of dense emergent vegetationand open water. Hawaiian coots mayprefer a similar mix but research onnesting habitat is limited. Large, deepponds appear to provide only limitedhabitat for coots, particularly in areaswhere strong winds can cause theformation of wavelets. Interspersion ofrobust emergent vegetation can help toreduce wind fetch.

Loafing sites include logs, rafts ofvegetation, narrow dikes, mud bars,artificial islands, and "false nests." Coots also loaf on open bodies of watersuch as reservoirs. Because of theirability to disperse to find suitableforaging habitat, ephemeral wetlandsplay an important part in their annuallife cycle. Ephemeral wetlands maysupport large numbers of coots duringthe nonbreeding season (e.g., up to 25coots per hectare [10 per acre] year-round on Molokaì wetlands [Coleman1978; Engilis 1988], and concentrationsof 600 or more coots on Niìhau inwinter [HDLNR 1976-2003]).

3. Hawaiian Common Moorhen or<Alae <Ula

(a) Taxonomy. The Hawaiiancommon moorhen or <alae <ula(Gallinula chloropus sandvicensis) is anendemic subspecies of the commonmoorhen (Gallinula chloropus) (AOU1998). The Hawaiian subspecies is non-migratory and presumably originatedfrom stray migrant birds that colonizedHawaiì from North America (Nagata1983).

(b) Species Description. Although the Hawaiian commonmoorhen is recognized as distinct fromits North American relative, there are noevident plumage, soft body coloration,or measurement differences from formsin North America (Wilson and Evans1890 to 1899; Rothschild 1900). Hawaiian common moorhenssuperficially resemble the relatedHawaiian coot, but they are noticeablysmaller, possess a red shield over theirred and yellow bill, and have a whiteflank stripe (Schwartz and Schwartz1949; Bannor and Kiviat 2002). Theyare black above and slate blue below,with underwing coverts mostly white. Their legs and feet are yellowish green,and the feet are not lobed, as in the coot(Figure 8). The sexes are similar inappearance. Immature birds are olive-brown to grayish brown, with a paleyellow or brown bill.


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Figure 8. Hawaiian common moorhen. Photo by Eric VanderWerf.

(c) Historical Range andPopulation Status. The Hawaiiancommon moorhen was found on all ofthe main Hawaiian Islands except L~naìand Kahoòlawe in 1891 (Munro 1960). However, by the late 1940's their statuswas considered "precarious," especiallyon Oàhu, Maui, and Molokaì(Schwartz and Schwartz 1949). Moorhens disappeared from Molokaìsometime after the 1940's and werereintroduced in 1983, but the populationdid not persist and the species currentlyis not known to occur on the island. Like the Hawaiian coot, the Hawaiianmoorhen is predominantly a species ofthe coastal plains, generally foundbelow 125 meters (410 feet) elevation.

The Hawaiian common moorhen isquite secretive and difficult to census,and even rough population estimateswere lacking until the 1950's, so the

long-term population trend is difficult todetermine. Surveys in the 1950's and1960's estimated no more than 57individuals (Engilis and Pratt 1993). The spread of aquaculture on Oàhu inthe late 1970's and 1980's probably ledto an increase in the numbers ofmoorhens. In some locationsaquaculture projects support some of thehighest concentrations of moorhens inthe State (Engilis 1988; M. Silbernagle,USFWS, pers. comm. 2000) althoughwetlands managed for moorhens havethe potential to support highconcentrations as well.

(d) Current Range andPopulation Status. Hawaiiancommon moorhens are currently foundon the islands of Kauaì and Oàhu. Biannual waterbird surveys provide arough idea of recent population trends,but an accurate population estimate isnot available due to the secretive natureof this species and its use of denselyvegetated wetland areas. Counts ofmoorhens have been stable, but remainlow, with average totals of 314 birdsover the past 5 years (1998 to 2001 and2003; Figures 9 and 10) (HDLNR 1976-2003). The inaccuracy of currentmethodology used in the biannualwaterbird count, which involvesrelatively brief visits to each wetland(Griffin et al. 1989), is demonstrated bythe extreme differences in numbersbetween summer and winter waterbirdsurveys of lotus fields on Oàhu. In thewinter, after fields have been harvestedand visibility is greater, numbers may betwo to three times higher than the

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numbers seen during the summer surveyof the same areas. A more time-intensive point count method canprovide accurate assessments ofmoorhens at a given site (Chang 1990),but this method requires a substantialcommitment of resources. For example,the number of moorhens detected atHamakua Marsh during waterbirdcounts is low (average of 3.8 moorhensfrom 2000 to 2002), but repeated carefulobservations by Smith and Polhemus(2003) for longer periods revealed 10moorhen pairs at the same site. Anothersurvey method that may enhancedetection of moorhens during surveys isthe use of tape playbacks, which havebeen used successfully for othermoorhen species and subspecies(Brackney and Bookhout 1982; Ribic etal. 1999; Takano and Haig 2004a).

i. Kauaì Population. Hawaiiancommon moorhens are widelydistributed in lowland wetlands andvalleys on Kauaì (Figure 22, page 53). Sizable populations exist in the Hanaleiand Wailua River valleys, WaiakaluaReservoir, and Wilcox Ponds. Theirrigation canals on the M~n~ Plain ofwestern Kauaì also support birds, butaccurate counts have proven logisticallydifficult (T. Telfer, pers. comm. 1988). Dense vegetation around lowlandreservoirs may also support moorhens,but nesting is limited by deep water andsevere water level fluctuations. Moorhens are also found in wetlandagricultural areas such as taro fields.

ii. Oàhu Population. Moorhensare widely distributed on Oàhu, but aremost prevalent on the northern andeastern coasts between Haleìwa andWaim~nalo (Figure 14, page 33). Smallnumbers exist in Pearl Harbor, whereforaging occurs in semi-brackish water. The population on the leeward coast islimited to Lualualei Valley. Based onbiannual waterbird surveys during thepast 5 years, Oàhu holds approximatelyhalf of the State’s total population ofmoorhens (Figures 9 and 10).

iii. Maui and MolokaìPopulations. In the past, moorhenswere observed regularly on Maui, withunsubstantiated reports of moorhen fromthe Keànae Peninsula (Shallenberger1977). Six marked birds were releasedby U.S. Fish and Wildlife Service staffat Kakahaià National Wildlife Refugeon Molokaì in June 1983. At least twobirds were still present in January 1984,but there have been no confirmedsightings since 1985 (USFWS, unpubl.data).

iv. Hawaiì Population. Thereare unsubstantiated reports of moorhenobserved on the Big Island (HDLNR,unpubl. data), but no confirmed reports.

(e) Life History. Little is knownof the Hawaiian common moorhen'sbreeding biology. Most nests areinconspicuously placed within denseemergent vegetation over shallow water. Moorhens generally nest in areas withstanding freshwater less than 60centimeters (24 inches) deep. The


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emergent vegetation is folded over intoa platform nest (Shallenberger 1977). Where emergent aquatic vegetation isinsufficient, nests may be placed on theground, but most have tall cover nearby. Apparently, the particular species ofemergent plant used for nestconstruction by moorhens isunimportant as long as it is a robustemergent (Weller and Fredrickson1973).

Like other common moorhensubspecies, the Hawaiian commonmoorhen is territorial. Territory size ofnesting pairs at Hamakua Marsh onOàhu ranged from 853 to 2,416 squaremeters (9,182 to 26,006 square feet)(Smith and Polhemus 2003). Nestingoccurs year-round, but most activityextends from March through August andis influenced by water levels andvegetation growth (Shallenberger 1977;Byrd and Zeillemaker 1981; Chang1990). Clutch size differed among 2island investigations, where it averaged4.9 eggs on Kauaì (n = 87 nests)(Chang 1990) and 5.6 eggs on Oàhu (n= 64 nests; Byrd and Zeillemaker 1981). An average clutch size of 8.4 eggs wasreported from seven North Americanmoorhen sites (Byrd and Zeillemaker1981). The incubation period rangesfrom 19 to 22 days (Byrd andZeillemaker 1981). Moorhens are aprecocial species; chicks are coveredwith down and are able to walk, but aredependent on the parents for severalweeks. Renesting and multiple broodsduring one season have been observed(Byrd and Zeillemaker 1981). Brood

sizes have been observed to range from2 to 7 chicks (mean of 4.4 chicks perbrood) at Hamakua Marsh, Oàhu(Smith and Polhemus 2003).

Little information is available on thefeeding habits of the Hawaiian commonmoorhen. Food items consumed by thissubspecies may include algae, aquaticinsects, and mollusks (Schwartz andSchwartz 1949). Telfer (unpubl. data)found remains of snails, guava seeds,algae, and other plant material instomachs of road-killed moorhens onKauaì. Seeds of grasses, parts ofvarious plants, and other types ofinvertebrates are probably also includedin the moorhen's diet. These birds areapparently opportunistic feeders, so thediet may vary with the particular habitat(Shallenberger 1977).

Hawaiian common moorhens are themost secretive of the native Hawaiianwaterbirds, preferring to forage in denseemergent vegetation. Most birdsfeeding along the edge or in the openquickly seek cover when disturbed. Moorhens are good swimmers and oftencross open water to reach foraging sites. They are generally sedentary; however,moorhens readily disperse in spring,presumably to breed (Nagata 1983). Dispersal may occur in relation to dryand wet periods (Engilis and Pratt1993). This pattern also occurs in asimilar island common moorhensubspecies, the Mariana commonmoorhen (Gallinula chloropus guami),where moorhens exhibited reducedbreeding and natal site tenacity. This


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was presumably in response to resourceshifts caused by flooded habitat andcreation of new seasonal habitat, andpossibly behavioral changes as juvenilesdispersed to other wetlands (Takano2003). Mariana common moorhenshave been also documented to movebetween islands in response to highrainfall during the wet season andcreation of new habitat (Worthington1998; Takano and Haig 2004b). Whether the Hawaiian commonmoorhen is capable of inter-islandmovement is unknown.

(f) Habitat Description. Hawaiian common moorhen habitatconsists of freshwater marshes, taropatches, lotus fields, reedy margins ofwater courses (streams, irrigationditches, etc.), reservoirs, wet pastures,and occasionally saline and brackishwater areas. The conversion ofaquaculture ponds in Kahuku, Oàhu,from fresh to salt water resulted in anobserved decline in moorhen numbers(Engilis and Pratt 1993). The densestmoorhen nesting areas are at the HanaleiNational Wildlife Refuge and taro fieldson the island of Kauaì, and at theKahuku and Ùkoà wetlands andWaialua lotus fields on Oàhu.

The key features of habitat areas formoorhens are: 1) dense stands of robustemergent vegetation near open water; 2)floating or barely emergent mats ofvegetation; 3) water depth less than 1meter (3.3 feet); and 4) fresh water asopposed to saline or brackish water. Interspersion of robust emergent

vegetation and open water is importantfor common moorhens on the mainland,and presumably is also for the Hawaiiansubspecies. The optimal overall ratio ofemergent vegetation to open water is50:50 (Weller and Fredrickson 1973). Continued management of wetland areasis necessary to maintain these habitatconditions.

4. Hawaiian Stilt or Aeò

(a) Taxonomy. The Hawaiian stiltor aeò (Himantopus mexicanusknudseni) is part of a cosmopolitansuperspecies complex including theblack-necked stilt (Himantopusmexicanus) of North and SouthAmerica, the black-winged stilt (H.himantopus) of Eurasia and Africa, andpied stilt (H. leucocephalus) and blackstilt (H. novazelandiae) from Australasia(Robinson et al. 1999). The Hawaiianstilt is clearly allied with the black-necked stilt and is considered a distinctsubspecies (AOU 1998). Colonizationof Hawaiì by stilts probably resultedfrom North American vagrants.

(b) Species Description. Thestilt is a slender wading bird, blackabove (except for the forehead) andwhite below with distinctive long, pinklegs (Figure 11-A). The Hawaiian stiltdiffers from North American black-necked stilts by having black extendinglower on the forehead as well as aroundto the sides of the neck, and by having alonger bill, tarsus (lower leg), and tail(Coleman 1981; Robinson et al. 1999).


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Figure 11-B. Juvenile Hawaiian stilt. Photo by Eric VanderWerf.

Figure 11-A. Adult male Hawaiian stilt. Photo by Eric VanderWerf.

Sexes are distinguished by the color of the back feathers (brownish in females,black in males) as well as voice (lowerin females). Downy chicks are wellcamouflaged, tan with black speckling. Immatures have a brownish back andmore extensive white on the cheeks andforehead (Pratt et al. 1987; Figure 11-B). Immature birds produce a sharppeeping call. The total length of adultHawaiian stilts is about 40 centimeters(16 inches).

(c) Historical Range andPopulation Status. Hawaiian stiltswere historically known from all of themajor islands except L~naì andKahoòlawe (Paton and Scott 1985). Prior to 1961, documented records ofHawaiian stilts on the island of Hawaiìwere limited to three collected by S. B.Wilson in the late 1800's and possiblyone collected by Collett prior to1893(Banko 1979). As with the otherHawaiian waterbirds, there are noestimates of historical numbers. However, extensive wetlands andaquatic agricultural lands historicallyprovided a fair amount of habitat. Lossof this habitat undoubtedly caused adecrease in stilt numbers. It has beensuggested that the population haddeclined to approximately 200 birds bythe early 1940's (Munro 1960). Thisnumber, however, may have been anunderestimation of the population, asother estimates from the late 1940'splace the population at approximately1,000 birds (Schwartz and Schwartz1949). This number may still be a lowestimate, as a sizable number of stiltscan be found seasonally on Niìhau,which was not surveyed in the 1940's. The Hawaiian stilt was a popular gamebird, and hunting contributed to localpopulation declines until waterbirdhunting was prohibited in 1939(Schwartz and Schwartz 1949).

(d) Current Range andPopulation Status. Hawaiian stiltsare currently found on all of the mainHawaiian Islands except Kahoòlawe. The first stilts on L~naì were

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Figure 12 . Hawaiian stilt w in te r counts, based on b iannua l waterb ird counts from 1976 to 2003.

N ote : In 1982-3 ,1996, 2002, and 2003 no t a ll routine ly surveyed wetlands on a particu la r is land were covered during sum m er surveys. C ounts on the fo llow ing is lands and years m ay be erroneously low :1982,1883 – Kaua’i1984, 1996, 2003 – H awai’i2002 – Kaua’i and Hawai’i

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Figure 13 . Hawaiian stilt sum m er counts, based on b iannua l waterb ird counts from 1976 to 2002.

N ote : In 1982,1984,1996, and 2002, no t a ll rou tinely surveyed wetlands on a particu la r is land were covered during sum m er surveys. C ounts on the fo llow ing is lands and years m ay be erroneously low :1982 – O ’ahu and K aua ’i1984, 1996 – Hawai’i2002 – Kaua’i and Hawai’i

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documented in 1989 at the L~naì Citywastewater treatment ponds (Engilis andPratt 1993; M. Ueoka, Hawaiì Divisionof Forestry and Wildlife, pers. comm.1993). Based on biannual Hawaiianwaterbird surveys from 1998 through2003 (2002 was excluded because ofmissing data), the stilt populationaveraged 1,350 birds, but fluctuatedbetween 1,200 and 1,500 birds (Figure12; HDLNR 1976-2003). The censusmethod used during these surveysappears to provide an accurate picture ofthe number of stilts at a site (Chang1990). Summer counts were notaveraged because these counts aregenerally more variable than wintercounts due to the variability in hatch-year bird survival (Reed and Oring1993).

Long-term census data indicatestatewide populations have beenrelatively stable or slightly increasingfor the last 30 years (Reed and Oring1993; Figures 12, 13). As with coots,census data show year-to-yearvariability in the number of stiltsobserved. This variability can bepartially explained by rainfall patternsand reproductive success (Engilis andPratt 1993). Hawaiian stilts readilydisperse between various islands andcollectively the Hawaiian islandpopulations constitute onemetapopulation (Reed et al. 1994,1998).

i. Kauaì and NiìhauPopulations. Considerable movementof Hawaiian stilts occurs between thesetwo islands, apparently in response to

rainfall patterns and the flooding anddrying of Niìhau's ephemeral lakes(Engilis and Pratt 1993). On Kauaì,stilts are numerous in large river valleyssuch as Hanalei, Wailua, and Lumahaì,and on the M~n~ Plain (Figure 17, page40). Stilts also frequent Kauaì'sreservoirs, particularly duringdrawdown periods, as well as sugarcaneeffluent ponds in L§huè and Waimea.

Over the past 5 years (excluding

2002 because of missing data), the stiltpopulation on Kauaì has fluctuatedbetween approximately 125 to 350 birds(HDLNR 1976-2003). Niìhau canpotentially support a large number ofstilts when the extensive ephemerallakes are flooded.

ii. Oàhu Population. Oàhusupports the largest number of stilts inthe Hawaiian Islands (Engilis 1988;HDLNR 1976-2003). Largeconcentrations of stilts can be found atthe James Campbell National WildlifeRefuge, the Kahuku aquaculture ponds,the Honouliuli and Waiawa units of thePearl Harbor National Wildlife Refuge,and on Nuùpia Ponds in K~neòhe. Populations also exist at the ChevronRefinery, the fishponds at Kualoa BeachPark, at Salt Lake District Park, and atscattered locations along the northernand eastern coasts. Over the past 5years, Oàhu accounted for 35 to 50percent of the State’s stilt population,with approximately 450 to 700 birdscounted during any single year (HDLNR1976-2003).


29

iii. Maui, Molokaì, and L~naì(Maui Nui) Populations. Maui's twolarge coastal wetlands, Kanah~ andKe~lia, support a significant number ofHawaiian stilts, with important nestinghabitat at Ke~lia. Monthly countsindicate that birds freely move betweenthese two wetlands, apparently in searchof optimal foraging habitat (Ueoka1979). A small number of stilts alsofrequent aquaculture areas on Maui. Over the past 5 years, stilt numbers haveranged from approximately 250 to 530birds (HDLNR 1976-2003).

Molokai's south coast wetlands andplaya lakes are, at times, importanthabitats for stilts, with largeconcentrations at the KaunakakaiSewage Treatment Plant. There is someevidence of periodic movements of birdsbetween Maui and Molokaì, againprobably in response to availableforaging habitat (Engilis and Pratt1993). Since 1968, statewide waterbirdsurveys have shown a significantincrease in stilts on Molokaì (Reed andOring 1993). On Molokai, the stiltpopulation has fluctuated betweenapproximately 25 to 90 birds over thepast 10 years.

Hawaiian stilts are now permanentresidents at the L~naì City wastewatertreatment pond. They have beenrecorded there annually since the pondsbecame operational in 1989 andnumbers sometimes exceed 100 birds(HDLNR 1976-2003).

iv. Hawaiì Population. TheKona Coast from Kawaihai Harborsouth to Kailua supports the largestnumber of stilts on the Big Island, withMakalawena and Àimakap~ Pondsbeing key breeding areas (Figure 18,page 43). Until recently, the CyanotechPonds were a key breeding area becausemanagement focused on providingadequate breeding habitat for stilts tominimize nesting attempts in hazardousareas (Waddington 2003). For a varietyof reasons, these ponds are no longeravailable to stilts, and we are workingwith Cyanotech and the State to identifyother suitable nesting habitats onHawaiì for stilts displaced fromCyanotech (J. Kwon, USFWS, pers.comm. 2004).

Hawaiian stilts can also be foundalong the H~m~kua Coast and in theKohala river valleys of Waipio,Waimanu, and Pololã (Figure 18). Thescattered anchialine2 ponds along theKona Coast are important feeding sites. Hawaiian stilts have become numerousat the Kona (Kealakehe) wastewatertreatment plant. The County of Hawaiìhas designed wildlife habitat forHawaiian stilts to fit within the 12-hectare (30-acre) perimeter around theKona Wastewater Treatment Plant. Comprehensive surveys on Hawaiìhave placed the Kona Coast populationat 130 birds (Ducks Unlimited 1996 to

2land-locked brackish-water poolsadjacent to the ocean, lacking surfaceconnection to the ocean but with asubterranean connection and showing adamping tidal fluctuation in water level


30

1997). Based on biannual waterbirdsurveys (1999 to 2002; 2003 is excludedbecause of missing data), there areapproximately 200 birds islandwide(HDLNR 1976-2003).

(e) Life History. Hawaiian stiltsprefer to nest on freshly exposedmudflats interspersed with low growingvegetation. The nest itself is a simplescrape on the ground. They have alsobeen observed using grass stems androcks for nesting material (Coleman1981; M. Morin, pers. comm. 1994). Nesting also occurs on islands (naturaland manmade) in fresh or brackishponds (Shallenberger 1977). Highernesting densities are found on largemudflat expanses interspersed withvegetation. Stilts have also beenobserved successfully using manmadefloating nest structures on Kauaì (T.Telfer, pers. comm. 1988) and floatingwooden platforms at Àimakap~Fishpond in Kona, Hawaiì (Morin1994, pers. comm. 1999). Stilts areterritorial and maintain an areaapproximately 14 to 30 meters (46 to 98feet) around nests (Robinson et al.1999).

The nesting season normallyextends from mid-February throughAugust, but varies among years, perhapsdepending on water levels. Stiltsusually lay 3 to 4 eggs that are incubatedfor approximately 24 days (Coleman1981; Chang 1990). Chicks areprecocial, leaving the nest within 24hours of hatching. Young may remain

with both parents for several monthsafter hatching (Coleman 1981). Parentsare extremely aggressive toward foreignyoung (Robinson et al. 1999).

A hatching success of 54 percent (n= 243 nests, 833 eggs) was reported forHawaiian stilts at the Kiì Unit of theJames Campbell National WildlifeRefuge (Chang 1990). Of the 243 totalnests observed at Kiì, 61 (25 percent)were lost to predation and 42 (17percent) were lost to flooding orabandonment (Chang 1990). Robinsonet al. (1999) reported 2.18 chickshatched per nest and 0.93 fledged perbrood for Hawaiian stilts. In a morerecent study at the James CampbellNational Wildlife Refuge, bullfrogs(Rana catesbeiana) were found to be themost important predators of young stiltsbased on tracking of birds fitted withradio transmitters (Eijzenga 2003).

Other predators of Hawaiian stilts

include mongooses, black rats (Rattusrattus), feral cats, feral dogs, black-crowned night herons (Nycticoraxnycticorax), cattle egrets (Bubulcusibis), Hawaiian short-eared owl or pueo(Asio flammeus sandwichensis), andcommon mynas (Acridotheres tristis)(Robinson et al. 1999). Stilts have avariety of antipredator behaviors, including mobbing aerial predators, a“popcorn display” (birds hopping andflapping around a ground predator), andstriking ground predators from behindwith their legs (Robinson et al. 1999). Because of their exposed nest sites, stilts


31

appear to be more susceptible to avianpredators than other Hawaiianwaterbirds.

Stilts are opportunistic feeders. They eat a wide variety of invertebratesand other aquatic organisms as availablein shallow water and mudflats. Specificorganisms taken include water boatmen(insects in the family Corixidae), beetles(order Coleoptera), possibly brine fly(Ephydra riparia) larvae, polychaeteworms, small crabs, fish (e.g.,Mozambique tilapia [Oreochromismossambica] and mosquito fish[Gambusia affinis]), and tadpoles (Bufospp.) (Shallenberger 1977; Robinson etal. 1999).

Feeding typically occurs in shallow

flooded wetlands. These types ofwetlands are ephemeral in nature andmay appear at any time of year, but areprimarily available in winter. Hawaiianstilts require specific conditions (waterdepths of 13 centimeters [5 inches] orless) for optimal foraging (Telfer 1973). Thus, intra- and inter-island movementis an important strategy for exploitingfood resources and has beendocumented between Oàhu and Mauiby statewide waterbird survey data andbanding studies (Ueoka 1979; Engilisand Pratt 1993; Reed et al. 1994; Reedet al. 1998).

(f) Habitat Description. Hawaiian stilts use a variety of aquatichabitats but are limited by water depthand vegetation cover. Stilts require

early successional marshlands withwater depth less than 24 centimeters (9inches) and favor perennial vegetationthat is limited and low growing such asnonnative pickleweed, California grass,and seashore paspalum or knotgrass(Paspalum spp.), or exposed tidal flats. Native low-growing wetland plantsassociated with stilt nesting areasinclude water hyssop, sea purslane(Sesuvium portulacastrum), and thesedges makaloa (Cyperus laevigatus)and kaluha (Bolboschoenus maritimus)(Robinson et al. 1999). Stilts may alsouse taro ponds where the full-grownvegetation forms a protective canopy. Stilts are rarely found in wetlands above200 meters (660 feet) elevation.

Ephemeral wetlands on Molokaì,Maui, and Niìhau are important forstilts. Management techniques thatmimic seasonal inundation andevaporation of freshwater mudflats arebeneficial to nesting stilts and provideinvertebrate forage for their young. Insular mudflats that are isolated fromterrestrial predators are still susceptibleto avian and amphibian predation. Onthe island of Hawaiì, anchialine pondsprovide important foraging habitat forthe Hawaiian stilt. Prawn farms, whichhave numerous ponds with changingwater levels, provide excellent foraginghabitat for adult birds.

Stilts generally forage and nest indifferent wetland sites, moving betweenthese areas daily. Adults with 3-day-oldchicks have been observed to move 0.5


32

kilometer (0.3 mile) from the nest site(Reed and Oring 1993). Nesting sitesare adjacent to or on low-relief islandswithin bodies of fresh, brackish, or saltwater. These include irrigationreservoirs and settling basins, natural ormanmade ponds, marshes, taro patches,silted ancient fish ponds, saltevaporation pans, and other wetlands.

Feeding habitat consists of shallowwater that is fresh, brackish, or saline. Freshwater sites include irrigationditches, reservoirs, settling basins, taropatches, sewage ponds, and marshes. Brackish-water feeding habitat consistsof coastal ponds, fish ponds, andestuaries. Saltwater feeding habitatincludes inshore reefs, beach areas, andtidal flats. Loafing areas include openmudflats, pickleweed flats, and pasturelands where visibility is good andpredator populations are low.

C. SPECIES DISTRIBUTION MAPS AND WETLAND IDENTIFICATIONTABLES

Figure 14. Waterbird populations at wetlands on Oàhu . . . . . . . . . . . . . . . . . . . p. 33Table 1. Locations of numbered wetlands on Oàhu shown in Figure 14. . . . .p. 34

Figure 15. Waterbird populations at wetlands on Maui. . . . . . . . . . . . . . . . . . . . p. 36Table 2. Locations of numbered wetlands on Maui shown in Figure 15. . . . . p. 37

Table 3. Locations of numbered wetlands on Molokaì and L~naì shown inFigure 16. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . p. 38

Figure 16. Waterbird populations at wetlands on Molakaì and L~naì. . . . . . . . p. 39

Figure 17. Waterbird populations at wetlands on Kauaì and Niìhau. . . . . . . . . p. 40Table 4. Locations of numbered wetlands on Kauaì and Niìhau shown in Figure

17. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . p. 41

Figure 18. Waterbird populations at wetlands on Hawaiì. . . . . . . . . . . . . . . . . p. 43Table 5. Locations of numbered wetlands on Hawaiì shown in Figure 18. . . p. 44

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Figure 14. Waterbird populations at wetlands on Oàhu. Values are 5-year averages using winter counts of adults only from1999 to 2003.


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Table 1. Locations of numbered wetlands on Oàhu shown in Figure 14.

Wetland Number on MapAirstrip Ponds 1Amorient (includes Ming + Romey’s) 2Apokaà Pond 3Chevron Refinery Ponds 4Coconut Grove 5Fort Kamehameha Reef Flats 6Gavin's Pond (Waiawa NWR) 7Haleiwa Lotus/Taro Fields 8H~m~kua Marsh 9Hawaiì Kai 10Hawaiì Prince Golf Course 11Heèia Marsh 12Honouliuli Unit Pearl Harbor NWR 13Hoòmaluhia Botanical Garden 14Kaèlepulu Mitigation Pond (Enchanted 15Kahuku Prawn Farm 16Kawainui Levee 17Kawainui Marsh 18Kiì Unit James Campbell NWR 19Kualoa State Park (`}pua Pond) 20Kuilima Sewage Treatment Plant 21L~ìe Prawn Farm 22Loko Ea Pond 23MCBH Clipper Golf Course 24MCBH Sewage Treatment Plant 25Mokul‘ìa Quarry 26Mokul‘ìa Ranch 27MÇliì Fish Pond 28Niuliì Reservoir 29Nuùanu Reservoir 30Nuùpia Ponds 31Olomana Golf Course 32Oneawa Canal 33PaikÇ Lagoon 34PC Watercress Farm 35Pouhala Marsh 36Punahoòlapa Marsh 37Punaluù Prawn Farm 38PunamanÇ Unit James Campbell NWR 39Airport Reef Runway 40Rubber Lined Pond 41


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Table 1 (continued). Locations of numbered wetlands on Oàhu shown in Figure 14.

Wetland Number on MapSalt Lake 42Turtle Bay Golf Course 43UH Mariculture Research Center 44UH Waialeè Agricultural Research 45Ùkoà Marsh 46Unisyn 47Waiawa Unit Pearl Harbor NWR 48Waimea Falls Arboretum 49Waipiò Soccer Field Wetlands 50

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Figure 15. Waterbird populations at wetlands on Maui. Values are 5-year averages using winter counts of adults only from1999 to 2003.


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Table 2. Locations of numbered wetlands on Maui shown in Figure 15.Wetland Number on MapAirport Drainage Ditch 1Azeka Ponds 1 and 2 2Cut Mountain 3Hailiimaile Treatment Pond 4Hansen Road Ponds (Reservoirs 70, 71) 5K~ànapali Golf Course Ponds 6Kahului Fairgrounds Drainage 7Kahului Oxidation Pond (HC&S Settling Pond) 8Kahului Settling Pond 9Kahului Sewage 10Kanah~ Pond Wildlife Sanctuary 11Kapalua Bay 12Kapalua Reservoir 13Kapalua Village 14Kauhi 15Ke~lia Pond and Wetlands 16Keànae Peninsula 17K-mart Settling Pond 18Lahaina Aquatic Center 19Maluaka Pond 20Mill Pond 21Nuù Pond 22Olowalu Reservoir 23Olowalu Reservoir 2 24P~niaka Pond 25Reservoir 20 26Reservoir 21 27Reservoir 22 28Reservoir 23 29Reservoir 26 30Reservoir 29 31Reservoir 32 32Reservoir 33 33Reservoir 35 34Reservoir 40 35Reservoir 42 36Reservoir 50 37Reservoir 51 38Reservoir 52 39


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Table 2 (continued). Locations of numbered wetlands on Maui shown in Figure 15.

Wetland Number on MapReservoir 60 40Reservoir 61 41Reservoir 72 (Æmaòpio) 42Reservoir 73 (Waiàle) 43Reservoir 80 44Reservoir 81 45Reservoir 82 46Reservoir 84 47Reservoir 90 (Airport Village) 48Reservoir 92 49Ukumehame Settling Pond + Reservoirs 50Waiheè Wetlands 51

Table 3. Locations of numbered wetlands on Molokaì (Mo) and L~naì (L) shown inFigure 16.

Wetland Island Number on MapKakahaià NWR Mo 1Kaluaapuhi Fish Pond Mo 2Kaluakoì Golf Course Mo 3KamalÇ Flats Mo 4Kaunakakai River Mo 5Kaunakakai Sewage Treatment Plant Mo 6Kualapuù Reservoir Mo 7Maunaloa Sewage Treatment Plant Mo 8`Æhiàpilo Mo 9Oliwai Sewage Treatment Plant Mo 10Paialoa Fish Pond Mo 11L~naì City Oxidation Ponds L 1

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Figure 16. Waterbird populations at wetlands on Molokaì and Lanaì. Values are 5-year averages using winter counts of adults onlyfrom 1999 to 2003.

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Figure 17. Waterbird populations at wetlands on Kauaì and Niìhau.Values are 5-year averages using winter counts of adults only from 1999 to 2003 for Kauaì and 1993, 1995,1996, 1997, and 1999 for Niìhau.


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Table 4. Locations of numbered wetlands on Kauaì (K) and Niìhau (N) shown inFigure 17.

Wetland Island Number on MapAeopoalua Reservoir K 1Aepo Reservoir K 2Aepoeha Reservoir K 3De Mello Reservoir K 4Halen~nahu Reservoir K 5Hanalei N.W.R K 6Hanalei Post Office Taro Fields K 7Hanalei Trader Taro Fields K 8Hanap‘p‘Taro Fields K 9Hanini Reservoir K 10Hukiwai Reservoir K 11Hul‘ìa National Wildlife Refuge K 12Ioleau Reservoir K 13Kahelunui Reservoir K 14Kailiìliainale (Okinawa) Res. K 15Kalihiwai Reservoir K 16Kalihiwai River Estuary K 17Kapaà Stream Estuary K 18Kapaia Reservoir K 19Kauaì Lagoons Westin K 20Kaumakani Gulch Pond K 21Kaupale Reservoir K 22Kawailele Sand Mine K 23Kekaha Landfill (Leachate) Pond K 24Kekaha Slaught. House Res K 25Kekaha Sugar Company Settling Basin K 26K§lauea Stream Estuary K 27K§pã Reservoirs 1-4 K 28K§pã Road Reservoir K 29Kolo Reservoir K 30KÇloa (Kukuiùla) Sewage Pond K 31KÇloakapohu Reservoir K 32Kumano Reservoir K 33Lauwai Reservoir K 34L§huè Settling Basin K 35Lono Reservoir K 36Lumahaì River K 37M~n~ Base Pond K 38M~n~ Ditches & Drains K 39M~n~ House Reservoir K 40M~n~ Reservoir K 41Mauka Reservoir K 42


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Table 4 (continued). Locations of numbered wetlands on.Kauaì (K) and Niìhau (N)shown in Figure 17.

Wetland Island Number on MapMenehune Fish Pond K 43Morita Reservoir K 44Niu Valley Reservoir K 45Olokele Settling Basin Reservoir K 46`Æmaò Reservoir K 47`Æpaekaà Valley K 48P~puaà Reservoir K 49Pia Mill Reservoir K 50Princeville Golf Course Ponds K 51Puù Ka Ele Reservoir K 52Puù O Hewa Reservoir K 53Puù O Papai Reservoir K 54Saki Mana Reservoir K 55Sloggett Reservoir K 56Smith's Tropical Paradise K 57Twin Reservoir K 58U.S. Navy Sewage Treatment Pond K 59Waiakalua Reservoir K 60Waiawa Reservoir K 61Wailau Siphon Reservoir K 62Wailua Golf Course Pond K 63Wailua Jail Swamp K 64Waimea Heights Reservoir K 65Waimea Taro Fields K 66Wainiha River Taro Fields K 67Waioli Taro Fields K 68Waiopili Spring Quarry K 69Waipa Taro Fields K 70Wait~ Reservoir K 71Wilcox Ponds K 72`}pana Reservoir N 1Hal~liì Ditches N 2Hal~liì Lake N 3Halulu Lake N 4Kaununui Ponds N 5Kièkiè Ponds N 6L‘àhi Pond N 7Nonopapa Lake N 8Palikoaè Ponds N 9PÇhueloa Valley Pond N 10Puù Àlala Pond N 11Puù Wai Pond N 12

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Figure 18. Waterbird populations at wetlands on Hawaiì. Values are 5-year averages using winter counts of adults onlyfrom 1999 to 2003.


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Table 5. Locations of numbered wetlands on Hawaiì shown in Figure 18.

Wetland Number on MapAhn's Pond 1Àimakap~ Pond 2Cyanotech 3Keaàu Pond (Shipman) 4Kealakehe (Kona) Sewage Treatment Plant 5Keanakolu Road Stock Ponds 6Kehena Reservoir and Ponds (1-5) 7Loko Waka Pond 8Nakagawa Pond 9`Æpaeùla Pond 10P~iakuli Reservoir 11Punaluù Pond 12Puù Pã`lehu Reservoir 13Slatter Pond 14Wai~kea Pond 15Waipuhi Ponds (1 and 2) 16

D. REASONS FOR DECLINE ANDCURRENT THREATS

The most important cause of declineof these four species of endangeredHawaiian waterbirds is loss of wetlandhabitat. Other factors that havecontributed to population declines, andwhich continue to be detrimental,include predation by introducedanimals, altered hydrology, alteration ofhabitat by invasive nonnative plants,disease, and possibly environmentalcontaminants. Hunting in the late1800's and early 1900's took a heavy tollon Hawaiian duck populations, and to alesser extent on populations of the otherthree species (Swedberg 1967). Currently, predation by introducedanimals may be the greatest threat to thecoot, moorhen, and stilt, andhybridization with feral mallards (Anas

platyrhynchos) is the most serious threatto the Hawaiian duck.

The identified threats to theHawaiian waterbirds are each classifiedaccording to the five factors identifiedunder section 4(a)(1) of the EndangeredSpecies Act in consideration for listing,delisting, and reclassification decisions. These five factors are as follows:

A — The present or threateneddestruction, modification, or curtailmentof its habitat or range;

B — Overutilization forcommercial, recreational, scientific, oreducational purposes;

C — disease or predation;D — the inadequacy of existing

regulatory mechanisms;E — other natural or manmade

factors affecting its continued existence.


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1. Loss of Wetland Habitat(Factor A)

A significant amount of Hawaiì’swetlands have been filled or otherwisemodified and are now occupied byhotels, housing developments, golfcourses, shopping centers, landfills,military installations, highways, formersugarcane fields, and industrial sites. Hawaiì contains approximately 44,320hectares (110,800 acres) of wetlands anddeep freshwater habitats, of which 81percent are classified as palustrinescrub-shrub forest habitats, which arenot used by Hawaiì’s four endangeredwaterbirds. This wetland class islocated at mid- to high elevations andoccurs as bogs and rainforestecosystems. The waterbirds addressedin this recovery plan primarily utilizewetlands that exist within the coastalplains of Hawaiì, of which an estimated8,990 hectares (22,475 acres) existedcirca 1780 (USFWS 1990). By 1990,however, only an estimated 6,190hectares (15,474 acres) of thesewetlands remained, a decrease of 31percent (Dahl 1990).

Wetland agriculture (taro, lotus, andrice) has provided additional managedwetlands for waterbirds since the arrivalof the first Polynesians (Stone 1989). As early as the 1850's, significant lossesof this type of habitat began with thepartial replacement of taro by otheragricultural crops (e.g., sugarcane) andby development for an expandingindustrial society (Bostwick 1982). Thisgradual loss of natural and agriculturalwetlands has continued to the present. Sugar plantations provided a limitedamount of habitat via settling basins and

reservoirs. The collapse of thesugarcane industry has resulted in thedraining of many of these reservoirs andbasins, which were widely utilized byresident waterbirds, migratorywaterfowl, and migratory shorebirds.

Hawaiian common moorhens havebecome dependent in some areas uponmodern aquacultural wetlands (used forraising, for example, taro or shrimp) fortheir survival (Engilis and Pratt 1993),and many other bird species also usethese wetlands. The majority ofaquacultural wetlands occur on Oàhu. The industry reached its peak in themid-1980's and is now declining.Waterbirds are occasionally implicatedas a cause of depredation on taro andprawn farms. Suspected depredationmay result in efforts by farmers to placeexclusion devices around ponds thatwould effectively eliminate some habitatpresently utilized by waterbirds.

Many of Hawaiì’s wetlands occurin coastal areas that are highly valuedfor development and are becomingincreasingly urbanized. This urbanencroachment raises concerns regardinghuman disturbance, urban runoffimpacts on water quality, and anincreased incidence of domestic cats anddogs in wildlife areas (Brown andDinsmore 1986; Reid 1993). Development pressure in wetland areashas been most prevalent on the islandsof Oàhu and Maui, but is increasing onall islands. Urban development hasencroached upon both Kanah~ andKe~lia Ponds on Maui, and theHonouliuli Unit of Pearl HarborNational Wildlife Refuge is nowsurrounded by urban development. If


46

hotels and golf courses on the KahukuPlain of Oàhu expand, ephemeralwetlands that are utilized by waterbirdswill be lost to development.

2. Hunting (Factor B)

Indiscriminate hunting of migratorywaterfowl in the late 1800's and early1900's took a heavy toll on Hawaiianduck populations. During this period, ashabitat size and quality decreased, directpressure on waterbird populationsincreased. When bag limits wereintroduced, they were generous (25ducks, including both Hawaiian ducksand mainland duck migrants, per dayover a 4-month season) and difficult toenforce. In 1925, the Territorial Fishand Game Commission closed theHawaiian duck season, but because oftheir similarity to female mallards andpintails, Hawaiian ducks probablyreceived little protection (Swedberg1967). A total ban on waterfowlhunting, initiated in 1939 and which isstill in effect today, provided importantprotection for the remaining Hawaiianducks (Bostwick 1982). Althoughoverhunting contributed to the historicaldecline of the Hawaiian duck, it is notconsidered a current threat to thespecies.

3. Predators (Factor C)

The introduction of alien predatorshas had a negative impact onpopulations of all four endangeredwaterbirds (Griffin et al. 1989). Birdson the Hawaiian Islands evolved in theabsence of mammalian predators, andare consequently highly vulnerable tothese introduced animals. Mongooses

were first introduced to the island ofHawaiì in 1883, subsequently to Maui,Molokaì, and Oàhu, and it is possiblean incipient population exists on Kauaì(K. Gundersen, Kauaì Invasive SpeciesCommittee, pers. comm. 2004). Mongooses have become a seriousthreat to waterbirds throughout theseislands, taking eggs, young birds, andnesting adults. Feral cats becameestablished in Hawaiì shortly afterEuropean contact and were common inOàhu forests as early as 1892 (Tomich1969). Cats range from sea level to atleast 2,900 meters (9,500 feet) on theBig Island (Hu et al. 2001) and 3,055meters (10,000 feet) on Maui (Hodgesand Nagata 2001). The proliferation offeral cat feeding stations near parks andother areas that support waterbirds mayhave a significant effect on waterbirdrecovery in these areas. Dogs havebecome a serious problem in somewetlands, particularly near urban areas. Although direct evidence is lacking, ratsmost likely have a negative effect on thewaterbirds as well (Atkinson 1977). Rats are known to be one of the primarypredators on the eggs and goslings ofthe endangered n‘n‘ (USFWS 2004c).

Other introduced species, such asthe cattle egret, bullfrog, and barn owl(Tyto alba), also have had negativeimpacts on waterbirds. The introducedbullfrog is a voracious predator of allsmall animals, and is known to eatyoung Hawaiian ducks (R. Walker,USFWS, pers. comm. 1982) and youngstilts (Robinson et al. 1999; Eijzenga2003). Barn owls have been observedtaking adult stilts and are presumed totake chicks as well (K. Viernes,USFWS, pers. comm. 1994). Cattle


47

egrets play an unquantified role as apredator of nestling birds. Otherpredators on Hawaiian stilts include thealien common myna (Robinson et al.1999) and perhaps the native Hawaiianshort-eared owl or pueo.

In addition, both native andnonnative fish may prey uponendangered waterbirds. It is suspectedthat large fish in the Àimakap~Fishpond in Kona may be a source ofmortality for coot chicks (Morin 1994). It is believed introduced tilapia degradewaterbird feeding habitats by depletingthe invertebrate prey base used by thesebirds (C. Swenson, USFWS, pers.comm. 2004). Native barracuda(Sphyraena barracuda) in NuùpiaPonds on Oàhu are suspected of eatingyoung stilts (C. Swenson, pers. comm.2004).

The problems posed by thesepredators are magnified by a severeshortage of protected nesting areas. Theimportance of core wetland areas,permanent habitat that supportssubstantial numbers of Hawaiianwaterbirds, is most evident duringdrought periods when waterbirdpopulations become concentrated. These sites must be protected andmanaged to recover Hawaiì’swaterbirds. During drought periods,nesting, foraging, and loafing sitesbecome limited and overcrowding canresult. Predator numbers then rapidlyincrease in response to this concentratedfood source. This type of predatorresponse has been well documented inNorth America and is summarized bySargeant and Raveling (1992).

4. Alteration of Hydrology (FactorA)

Hydrologic alterations of wetlands,such as flood control andchannelization, often make habitat lesssuitable or unusable for nativewaterbirds because they alter both waterdepth and timing of water levelfluctuations. Hawaii*s waterbirds maybe unable to adjust their breedingbehavior to accommodate thesemodifications, possibly resulting indecreased reproductive success. Inaddition, the depletion of freshwateraquifers causes salt water intrusion intocoastal ground water, altering thesalinity levels in associated wetlands. Although stilts and coots will usebrackish water, moorhens and Hawaiianducks do so only rarely. In addition,fluctuations in salinity levels alter thespecies composition of the vegetationand arthropod communities, thusimpacting food availability for thewaterbirds. At Nuùpia Ponds onO’ahu, mean salinity varied from 35 to64 ppt (parts per thousand) (HawaiìDivision of Forestry and Wildlife 1978),and in a study on Kauaì, salinity rangedfrom a low of 4 ppm (parts per million)to a high of 68 ppm (Coleman 1981). Such changes in hydrology highlight theneed for secure water sources for boththe core and supporting wetlandsidentified in this recovery plan (seeRecovery Strategy, page 65). Analysisand management of hydrology are vitalto managing waterbird habitat.


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5. Invasion of Habitat byNonnative Plants (Factor A)

The alteration of wetland plantcommunities due to invasion bynonnative plants can greatly reduce theusefulness of wetland areas for nativewaterbirds. Nonnative plant control is akey problem facing wetland managers inthe State of Hawaiì. Managers areconstantly faced with the challenge ofdeveloping techniques and then securingenough staff and funding to implementmanagement. Species such asCalifornia grass (Brachiaria mutica),pickleweed (Batis maritima), waterhyacinth (Eichornia crassipes), Indianfleabane (Pluchea indica), andmangrove (Rhizophora mangle) presentserious problems in most Hawaiianwetlands by outcompeting nativespecies and eliminating open water,exposed mudflats, or shallows(Shallenberger 1977).

6. Hybridization (Factor E)

The most serious threat specificallyaffecting Hawaiian ducks is geneticintrogression (the introduction of a genefrom one gene complex into another)through interbreeding with feralmallards (i.e. domesticated mallards thathave escaped and now breed in thewild). Wild, migratory mallards alsooccur in Hawaiì (Pyle 2002) butgenerally leave the islands before thebreeding season starts and thus are notthought to interbreed with Hawaiianducks. Reduction of wetland habitatmay increase opportunities forhybridization as populations ofHawaiian ducks and feral mallards areforced to share smaller wetland areas.

The distribution and abundance ofHawaiian ducks and mallard-Hawaiianduck hybrids is not clear in some areas,particularly Oàhu and Maui, due todifficulties in identification andinconsistency in attempting todistinguish hybrids. Determination ofthe population status of Hawaiian ducksand whether there are any pureHawaiian ducks left on Oàhu willrequire simultaneous genetic testing andmorphological characterization todevelop reliable morphological criteriafor distinguishing Hawaiian ducks,female mallards, and hybrids. Oncesuch criteria are available they can beused to identify birds for removal inorder to reduce interbreeding andintrogression. The number of hybridsapparently has increased rapidly onsome islands in recent years (Figures 19through 26); this pattern is no doubtreal, but it is possible that hybridizationhas been occurring for some time andthe apparently rapid increase is due togreater realization of the hybridizationproblem and more careful identificationof Hawaiian duck-like birds.

Kauaì has by far the largestHawaiian duck population and isthought to be largely free of hybrids,making it extremely valuable as apotential source of individuals fortranslocation or captive breeding andreintroduction to other islands. However, hybridization appears to bebeginning on Kauaì, and a fewHawaiian duck-mallard hybrids havebeen recorded at Smith’s TropicalParadise (Paradise Pacific) in the WailuaRiver bottoms, and possibly at HanaleiNational Wildlife Refuge (Figure 22). Mallards and known hybrids should be


49

removed from these and other sitesimmediately to stop hybridization andprevent introgression into the Hawaiianduck gene pool on Kauaì. BecauseKauaì represents the core of the speciesdistribution and is the only island thatlikely could provide birds forreintroduction to other islands, removalof feral mallards and hybrids on Kauaìis of the highest priority.

On Oàhu, Hawaiian ducks are stillreported in small numbers at some sites(Figures 19 and 23), but whether thesebirds are actually Hawaiian ducks orhybrids is not clear. Many areas onOàhu now have numerous feralmallards and mallard-Hawaiian duckhybrids, with the largest concentrationsin Kawainui Marsh, Oneawa Canal,Kaelepulu (Enchanted Lake),Hoòmaluhia, and the Hawaiì PrinceGolf Course. Although hybridization ismost severe on Oàhu, removal of feralmallards from Oàhu is a lower prioritythan on other islands because few or nopure Hawaiian ducks are left.

On Maui, most feral mallards arefound in the Kaànapali area, withsmaller numbers in the numerousreservoirs of the central valley (Figure20). All Hawaiian duck-like birds onKanah~ Pond recently have beenrecorded as Hawaiian ducks, while allthose at Ke~lia Pond have been recordedas hybrids, but it seems unlikely that thisapparent segregation is real; ducks couldmove easily between these sites, and thedifference is probably due to thedifficulty of identification in the field. Feral mallards have not been reportedon Molokaì or L~naì. Efforts shouldbe made to prevent their arrival.

On the island of Hawaiì, the largestconcentration of feral mallards is atWaiakea Pond in Hilo, which alsosupports many other exotic waterfowland may serve as a source of feralmallards that disperse across the island(Figure 21). Substantial numbers ofHawaiian ducks exist in the Kohala area,but hybrids have been reported recentlyin stock ponds on Kohala and MaunaKea (Figure 21; K. Uyehara, DucksUnlimited [formerly], pers. comm.2003). Hybridization appears to belimited on Hawaiì at this point, andmanagement of feral mallards andknown hybrids is a high priority beforethe problem worsens.

7. Avian Disease (Factor C)

The most prevalent disease affectingwaterbirds is avian botulism, which hasbeen documented at Æhiàpilo Pond onMolokai, Hanalei National WildlifeRefuge, Kauaì, Àimakap~ Pond onHawaiì, and at Ke~lia Pond NationalWildlife Refuge on Maui. It is causedby a toxin produced by anaerobicbacteria (Clostridium botulinum type Ca)in stagnant water. The disease mayreappear annually and can affect allnative and migratory waterbirds, causingflaccid paralysis which is evidenced bystaggering and the eventual loss of useof legs. Tracking of the location andtiming of avian botulism outbreaksmight reveal patterns that could be usedto avoid environmental conditions thatlead to outbreaks.

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Figure 19. Distribution and abundance of Hawaiian ducks (koloa), feral mallards, and mallard-Hawaiian duck hybrids onOàhu, based on winter counts from 1999 to 2003.

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Figure 20. Distribution and abundance of Hawaiian duck (koloa), feral mallards, and mallard-Hawaiian duck hybrids onMaui, based on winter counts from 1999 to 2003.

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Figure 21. Distribution and abundance of Hawaiian duck (koloa), feral mallards, and mallard-Hawaiian duck hybrids onHawaiì, based on winter counts from 1999 to 2003.

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evision • May 2005Figure 22. Distribution and abundance of Hawaiian ducks (koloa), feral mallards, and mallard-Hawaiian duck hybrids

on Kauaì, based on winter counts from 1999 to 2003.

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Figure 24. Mallard-Hawaiian duck hybrid winter and summer counts on Maui, based on biannual waterbird counts from 1999 to 2003.

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Figure 26. Mallard-Hawaiian duck hybrid winter and summer counts on Kauaì, based on biannual waterbird counts from 1986 to 2003.


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8. Environmental Contaminants(Factor E)

Environmental contaminants inwetlands are of concern to waterbirdrecovery because the general diet ofthese birds makes them susceptible totoxins accumulated in the food chain(Rattner 2000). In 1988, a fuel spill inPearl Harbor caused direct mortality andnest abandonment of native waterbirdsat the Honouliuli Unit of Pearl HarborNational Wildlife Refuge (J. Leinecke,USFWS, pers. comm. 1993). In 1996,an oil spill in Pearl Harbor imperiled theHawaiian stilt as well as marine fisheries(Pearl Harbor Natural Resource Trustees1999). Degradation of water qualityfrom urban encroachment on wetlandsalso has the potential to negativelyaffect waterbirds.

E. CONSERVATION MEASURES

A variety of conservation measureshave been implemented to protectHawaii`s endangered waterbirds. Theseefforts include a long-term hunting ban,protection of habitat throughestablishment and management ofrefuges and sanctuaries, populationmonitoring, research projects, release ofcaptive-bred Hawaiian ducks, andrestrictions on importation of mallards. Federal, State, and private entities haveall contributed to Hawaiian waterbirdrecovery. The major contributions ofthese entities are summarized below.

1. Federal and State Actions

Indiscriminate hunting of migratorywaterfowl in the late 1800's and 1900'stook a heavy toll on waterbird

populations, especially for the Hawaiianduck because of their similar appearanceto mallards and pintails. When baglimits were introduced they weregenerous and difficult to enforce. AllHawaiian waterbird species continued tobe hunted for several more decades. In1925, the Territorial Fish and GameCommission closed the Hawaiian duckseason, but because of their similarity tofemale mallards and pintails, Hawaiianducks probably received little protection(Swedberg 1967). A total ban onwaterfowl hunting in 1939, which is stillin effect today, provided importantprotection for the remaining Hawaiianducks (Bostwick 1982).

In 1952, the State designatedKanah~ Pond on Maui as the first Statewildlife sanctuary. Other Statesanctuaries include Kawaièle onKauaì, and H~m~kua Marsh, PaikÇLagoon, and Pouhala Marsh on Oàhu. In 1964, the U.S. Fish and WildlifeService (then called the Bureau of SportFisheries and Wildlife) and the HawaiìDepartment of Land and NaturalResources initiated studies of Hawaiianstilts and other waterbirds at Kanah~Pond.

Additional legal protection wasafforded these waterbirds with thepassage of Federal legislation forendangered species, including theEndangered Species Preservation Act of1966, the Endangered SpeciesConservation Act of 1969, and theEndangered Species Act of 1973. TheHawaiian duck and the Hawaiiancommon moorhen were declaredFederal endangered species in 1967(USFWS 1967). The Hawaiian coot and


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stilt were added to the Federalendangered species list in 1970(USFWS 1970).

The State Division of Forestry andWildlife (then called the Division ofFish and Game) initiated Hawaiian duckrestoration efforts in 1956 when theybrought Hawaiian ducks from Kauaìinto captivity at Pohakuloa, Hawaiì, tocreate a captive breeding population foruse in reestablishing the species on otherislands. The first release of 26 captive-bred Hawaiian ducks occurred in 1958at Kahua Ranch, Hawaiì (Engilis et al.2002). Releases of captive-bred birdscontinued on Hawaiì from 1968through 1979, with 361 birds released atKahua Ranch and 58 released in theHilo Forest Reserve. On Oàhu, 350Hawaiian ducks were released from1968 through 1982 (Engilis and Pratt1993). Feral mallards were not removedfrom the reintroduction sites on Oahuprior to the releases, however, resultingin extensive hybridization and geneticintrogression of mallards into thereestablished Hawaiian duck populationon that island. Hawaiian ducks werealso released on Maui from 1989 to1990, resulting in the establishment of asmall population, although hybridizationwith feral mallards has provenproblematic there as well (DucksUnlimited 1998).

In 1970, State and Federal biologistspublished an assessment of wetlandhabitats for endangered waterbirds(USFWS and HDLNR 1970). Animportant summary of the status ofHawaiì's wetlands followed thisassessment (Shallenberger 1977). Since1972, six National Wildlife Refuges

have been established for the protectionof waterbirds and their habitats: Hanaleiand Hul‘ìa on Kauaì, James Campbelland Pearl Harbor on Oàhu, Kakahaiàon Molokaì, and Ke~lia Pond on Maui. Two sanctuaries have also beendesignated on military lands for theconservation of Hawaiian waterbirds:Niuliì Ponds in Lualualei NavalMagazine and Nuùpia Ponds onKaneohe Marine Corps Base, both onOàhu. State and Federal efforts havenow protected 1,711 hectares (4,230acres) or 27 percent of the remaining6,190 hectares (15,475 acres) of coastalwetlands in Hawaiì.

In 1975, we established theHawaiian Waterbird Recovery Team. The mission of this team was to evaluateavailable data and develop a plan for therecovery of the Hawaiian coot,moorhen, and stilt (the Hawaiian duckwas not included in this originalrecovery plan). Limited informationwas available to the team due to the lackof statewide surveys and research oneach of the species.

The team recognized that theavailability of optimum habitat for thewaterbirds was key to maintaining self-sustaining populations of these species. Population target levels were based onexpected habitat carrying capacity andbest professional judgement. The firstHawaiian Waterbirds Recovery Planwas completed in 1978 (USFWS 1978). The primary objective of this recoveryplan, as defined by the team, was tomaintain self-sustaining populations ofat least 2,000 individuals of each speciesthroughout the island distributions andhabitats existing in 1976. Upon the


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accomplishment of this objective,downlisting and then delisting of thewaterbirds could be considered if thebirds maintained these target populationsizes and distributions for 3 and then 6years, respectively. Specificrecommendations discussed in theoriginal recovery plan included: 1)providing optimum habitat throughoutthe state for each endangered species tocomplete their life cycle (accomplishedthrough preservation and enhancementof primary habitat and development andenhancement of secondary and formerhabitats); 2) reducing adverse factorsaffecting waterbirds and their habitat,such as predation and/or encroachmentof wetlands by invasive nonnativeplants, to the lowest possible level; 3)preventing or moderating disastersadversely affecting the species inprimary habitats, including habitatmanagement to avoid disease; 4)monitoring populations to determinenumbers, status, and distribution and todetermine the progress of the statewiderecovery program; 5) fostering publicawareness and support of recovery planimplementation through an educationand information program; and 6)investigating the possibility of captiverearing and release of moorhens onMaui, Molokaì, and Hawaiì (USFWS1978).

The recovery plan was revised andupdated in 1985 to include the Hawaiianduck (USFWS 1985). While theprimary recovery objectives and timeframes remained the same, there weresome modifications in the primaryhabitats identified as needing protectionor management, based on changes inhabitat status. Specific

recommendations of the first revisedrecovery plan included: 1) providingprotection of suitable habitat insufficient abundance and distributionthroughout the State for each of the fourtaxa of waterbirds; 2) maximizingproductivity and survival of adults andyoung; 3) conducting management-related research to fill the gaps inrequired information; 4) continuingmonitoring of all populations ofwaterbirds; 5) maintaining pure geneticstocks of Hawaiian ducks; 6)supplementing existing or historicalpopulations of waterbirds, as needed;and 7) generating public awareness andsupport for the waterbird recoveryprogram through education andinformation.

This second draft of the second

revised recovery plan builds upon theprevious efforts. The goal of thissecond draft revised recovery plan is toidentify actions needed to downlistHawaiì’s four endangered waterbirdsfrom endangered to threatened statusand, ultimately, to remove them fromthe Federal list of threatened andendangered species (delisting). Stepsnecessary for the recovery of the fourendangered waterbirds include:increasing population numbers to astatewide baseline level; establishingmultiple self-sustaining breedingpopulations throughout each species’historical range; establishing a networkof wetlands on the main Hawaiianislands that are protected and managedfor waterbirds, including managementactions aimed at eradicating orcontrolling threats such as introducedpredators, disease, and contaminants;and for the Hawaiian duck in particular,


61

removing the threat of hybridizationwith feral mallards. The time frame forachieving these objectives has beenmodified in this revision of the planfrom 3 and 6 years for downlisting anddelisting, respectively, to 5 and 10years. The following section outlinesthe strategy and criteria for recoveryleading to the downlisting andeventually delisting of these endangeredspecies.

Studies initiated since the firstrecovery plan was published haveallowed the authors to modifypopulation target levels and identifymore specific recommendations for eachspecies. In this recovery plan,population target levels are based uponState waterbird biannual survey datacollected from 1976 through 2002, aswell as a population viability analysisfor the Hawaiian stilt. While thestatewide survey data providesinformation about population trends, apopulation viability analysis is neededfor the other three species to developpopulation targets that may serve asmore accurate predictors of long-termrecovery.

Over the past decades, State andFederal land managers have tested anumber of experimental managementtechniques that increase waterbirdproductivity, including development ofartificial nesting islets, floating neststructures, and eradication of theinvasive red mangrove (Rhizophoramangle) using mechanical clearing andherbicide treatments. Theseexperiments show promise forincreasing productivity of endangeredwaterbirds in habitats currently lacking

adequate nesting and foraging habitat. Use of windmills for watermanipulation, fencing and trapping tocontrol predators, and controllinghuman disturbance are additionalsuccessful management techniques thathave increased waterbird numbers.

Managers have also studied theconnectivity between wetland habitats,such as the study commissioned by theMarine Corps Base Hawaiì as part ofthe implementation of their IntegratedNatural Resources Management Plan. This study (Rauzon et al. 2002)examined wetland use by the Hawaiianstilt in the windward OàhuKoòlaupoko District. The goal of thisstudy was to increase understanding ofcurrent and potential habitatenhancements for the Hawaiian stilt on windward Oàhu and distribute thisinformation to help regionalstakeholders improve programs andactivities that might improve Hawaiianstilt recovery efforts there. Over thepast two decades, the Marine CorpsBase has worked to maintain Hawaiianstilt habitat on its properties andfacilitated events that promote Hawaiianstilt conservation and involve both thepublic and military personnel. Theiroverall goal is to contribute to regionalrecovery efforts of the Hawaiian stilt,with a view to building regionalpartnerships and strengthening the stiltpopulation outside of the core habitat onMarine Corps Base Hawaiì.

Additional research is needed to

develop appropriate census techniques,determine those parameters thatcharacterize a viable self-sustainingbreeding population, and to understand


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the behavior and biology of theseendangered waterbirds to allow us toeffectively manage for these species.

2. Private Actions

Significant research on the endemicwaterbirds of Hawaiì began in 1962with a study of Hawaiian ducks onKauaì supported by the World WildlifeFund. From 1980 to the present,research has been conducted to improveour biological knowledge of Hawaiì’sendangered waterbirds (Coleman 1981;Nagata 1983; Griffin et al. 1989; Chang1990; Engilis and Pratt 1993; Browne etal. 1993; Reed and Oring 1993; Reed etal. 1994, 1998; Eijzenga 2003; Smithand Polhemus 2003; Gee 2004). TheUniversity of Hawaiì conducts researchon wetland biology and ecology andoffers Sea Grant extension services onaquaculture and coastal conservation. Research on anchialine pools has beenconducted by the Oceanic Institute. TheUniversity of Hawaiì also administersthe Hawaiì Natural Heritage Programas part of the Center for Conservationand Training. The Hawaiì NaturalHeritage Program maintains a databaseof natural communities and rare andendangered species and has beeninstrumental in summarizing biannualwaterbird counts for the State. Theseresearch projects and data summarieshave enhanced our knowledge ofHawaiì’s waterbirds; however, manygaps still exist in our understanding ofthese species.

A variety of non-governmentalorganizations have also beeninstrumental in protecting Hawaiì’swetlands and endangered waterbirds.

Ducks Unlimited, a private wetlandsconservation organization, workscooperatively with State and Federalagencies, as well as with privatelandowners and local corporations, onwetlands conservation and habitatrestoration and protection efforts. In1997, Ducks Unlimited developed acomprehensive, cooperative plan toprotect and restore wetlands used bynative waterbirds in Hawaiì. DucksUnlimited has signed a Memorandum ofUnderstanding with the NaturalResources Conservation Service toundertake Wetlands Reserve Programprojects statewide.

In addition to Ducks Unlimited’sefforts, a variety of other conservationorganizations are contributing to therecovery of Hawaiì’s endangeredwaterbirds. The Nature Conservancymanages several ecological preserves inthe state. The Hawaiì Audubon Societyand the Sierra Club advocate on behalfof wetland protection. The NationalAudubon Society organizes the annualChristmas Bird Count, which providesanother tool for monitoring waterbirdpopulations. The Kawai Nui HeritageFoundation is a watchdog organizationthat oversees the future of KawainuiMarsh on Oàhu.

3. Partnerships

The recovery of Hawaiì’sendangered waterbirds cannot occurwithout the formation of strongpartnerships among Federal, State, local,and private groups. A variety ofpartnerships have been formed to protectand manage waterbird habitat. Examples of such partnership


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opportunities include our Pacific CoastJoint Venture, Partners for Fish andWildlife Program, Coastal Program, andHabitat Conservation Plan and SafeHarbor Agreement Programs; the multi-agency Coastal America program;restoration plans for hazardous materialsspills that target waterbird habitat; andthe Natural Resources ConservationService’s Wildlife Habitat IncentiveProgram (WHIP). Partnerships aim toencourage landowners and privatecitizens to protect and preservewaterbirds and their habitats throughcooperative agreements, funding, orhabitat restoration or creation projects. Partnerships with private landownersand conservation groups can assist landmanagers in acquiring and maintainingwetland habitats and developing andimplementing public awarenessprograms.

Examples of ongoing partnershipsare agreements with Chevron Refineryon Oàhu and Ùmikoa Ranch on theisland of Hawaiì. From 1993 to 2003,Chevron Refinery and the U.S. Fish andWildlife Service implemented the termsspecified in a Cooperative Agreement tomanage Rowland’s Pond as temporarynesting habitat for Hawaiian stilts,including predator control andvegetation management at Rowland’sPond, the impounding basin, andoxidation ponds. As a result of thisagreement, a total of 361 stilt chicksfledged at Chevron over the 10-yearperiod (L. Gibson, USFWS, pers.comm. 2004). The Safe HarborAgreement for Ùmikoa Ranch includedthe creation and maintenance (e.g.,fencing to exclude cattle and predatorcontrol) of 10 ponds for the Hawaiian

duck and Hawaiian goose over a periodof 20 years (J. Kwon, USFWS, pers.comm. 2004).

F. MONITORING

After World War II, State biologists,with Federal assistance, began aninvestigation of migratory waterfowl inthe belief that wintering populationsmight support a continued huntingprogram. Although hunting was neverreopened, this early study became thefoundation of a continuing program ofbiannual statewide waterfowl surveys,which was later expanded to include allendemic and migratory waterbirds.

Biannual counts, organized by theHawaiì Division of Forestry andWildlife, have been conducted statewidesince the mid-1950's, but coverage ofcertain areas was somewhat inconsistentuntil about 1976. Data from thesesurveys were recently compiled by theHawaiì Natural Heritage Program(under contract from the State ofHawaiì) and by the U.S. Fish andWildlife Service, making it possible toexamine a comprehensive data set ofwaterbird abundance for populationtrends from 1976 through 2003.

The biannual waterbird surveysconsist of visits to wetlands on allislands on a single day each winter andsummer, reducing the possibility ofcounting birds more than once as theymove among sites. In addition torecording the number of individuals ofall waterbird species at each wetland,surveyors collect information on waterlevel, vegetation cover, weatherconditions, and human disturbance.


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These surveys include the majority ofwetlands on each island, but a fewlocations that support waterbirds are notcovered. The numbers resulting fromthese surveys are thus minimum valuesand likely underestimate the actualpopulation by an unknown amount. These counts are probably fairlyaccurate population estimates for cootsand stilts in most years because thesespecies are relatively conspicuous andoften use open water areas. Hawaiiancommon moorhens and Hawaiian ducks,however, may be seriouslyundercounted since they are secretiveand often hide in densely vegetatedareas, in the case of the moorhen, or usemontane stream habitats that are notcovered in the biannual survey, in thecase of the Hawaiian duck. Niìhau hasnot been covered in surveys since 1999but supports many coots and stilts in wetyears. Returning Niìhau to the surveyswould increase their accuracy andutility.

The biannual waterbird count is thebest tool available for estimating therelative abundance of waterbirds and isextremely valuable for monitoring theirpopulations. The overall goal andmethodology of the count are sound, butimprovements could include greaterstandardization and consistency amongislands in the identification of Hawaiianducks, mallards, and hybrids; moreconsistent coverage of wetlands eachyear to increase comparability overtime; development of more accuratemethods of surveying Hawaiiancommon moorhens, possibly includingplaybacks; and inclusion of montanestream habitats to provide a morethorough estimate of the Hawaiian duck

population. Efforts are underway toimprove the utility of the count formonitoring populations of migratoryshorebirds (Engilis and Naughton 2004),including more thorough instructions forcounters and a photographic guide (E.VanderWerf, USFWS, pers. comm.2004; Appendix E).

Population values presented in thisplan are based on 5-year averages ofwinter counts from the biannualwaterbird survey (Figures 3, 4, 6, 7, 9,10, 12, 13). In most cases data from1999 to 2003 were used to calculate this5-year average, but in a few cases datafrom 1998 to 2003 were used becausedata from 2002 were missing. Althoughdata from both summer and wintercounts are presented, we used the wintercounts to examine population trendsbecause summer counts tend to be morevariable due to annual variation insurvival of hatch-year birds.

When compiling this data, we foundnumerous differences between thenumbers recorded on the original datasheets obtained from the State and thesummary values reported in previousversions of the recovery plan forHawaiian waterbirds (USFWS 1999).

The population data reported in thisplan are based on the original datarecorded wetland by wetland on eachisland, are verifiable, and are thereforeregarded as correct. Values in theprevious draft plan could not beverified, and were not consistentlyhigher or lower. Researchers andmanagers using previously availabledata are urged to confirm that theinformation they have is correct.


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II. Recovery

A. RECOVERY STRATEGY

The recovery of Hawaiì’sendangered waterbirds focuses onattaining adequate population sizes anddistribution of multiple self-sustainingpopulations throughout the historicalrange of each species. These foci arebased upon two widely recognized andscientifically accepted goals forpromoting viable self-sustainingpopulations: 1) the creation ormaintenance of multiple populations sothat a single or series of catastrophicevents will not result in the extinction ofthe species; and 2) increasing thepopulation size of each speciesthroughout its range to a level where thethreats of genetic, demographic(population dynamics), and normalenvironmental uncertainties arediminished (Mangel and Tier 1994;National Research Council 1995; Tear etal. 1995; Meffe and Carroll 1996). Furthermore, for these population anddistribution goals to ensure the long-term viability of the species requires thesuccessful control or elimination of thethreats identified in this plan. Bymaintaining minimum populationnumbers and self-sustaining breedingpopulations at multiple sites on multipleislands, the endangered waterbirds havea greater likelihood of achieving long-term survival and recovery.

The population size and distributionprescribed for recovery of the Hawaiianstilt are based on a population viabilityanalysis conducted by Reed et al.(1998), which estimated that stilts would

increase in number to a mean of 1,901(SD = 88) individuals in 200 yearsbased on current habitat conditions andother limiting factors. That number,rounded up to 2,000 to be conservative,was used as the basis for estimating thepopulation size required for recoverybecause apparently it is the carryingcapacity of the existing habitat. Furthermore, since population viabilityanalyses or other quantitative means ofestablishing population requirementshave not yet been developed for theHawaiian duck, coot, or moorhen, thepopulation size requirements for thesespecies are also based on the research onthe Hawaiian stilt and current populationestimates from the biannual statewidewaterbird survey, which represent thebest information available to date. Thepopulation size requirements for thesespecies should therefore be viewed asstarting points for the establishment ofrecovery targets and are subject torevision based on future research andstatistical analyses, as recommended inthis recovery plan.

Wetland protection andmanagement is crucial to maintain self-sustaining breeding populations ofwaterbirds. This recovery planidentifies a number of actions forimportant wetlands used by theHawaiian coot, duck, moorhen, and stilt. The recovery strategy for theendangered waterbirds relies on acombination of core and supportingwetlands, as defined below:


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Core Wetlands are areas thatprovide habitat essential to largerpopulations of Hawaiian waterbirds thatcomprise the bulk of the numbersprescribed for recovery. These sitesmust be protected and managed torecover Hawaiì’s waterbirds. AppendixA provides a brief description of thecore wetlands identified in this plan.

Supporting Wetlands areadditional areas that provide habitatimportant for smaller waterbirdpopulations or that provide habitatneeded seasonally by segments of thewaterbird populations during part oftheir life cycle. Protection andmanagement of these or similarwetlands is required to recoverHawaiì’s waterbirds, but there is roomfor some flexibility in regard to whichsites must be managed, and it is possiblethat other sites may fulfill the sameneeds as those listed here. Appendix Bprovides a brief description of thesupporting wetlands listed in this plan.

The core and supporting wetlandsidentified in Tables 6 through 9 arecurrently thought to be the sites on eachisland that provide the greatest potentialfor recovery of Hawaiian waterbirds. However, it is possible that in the futuresome of these sites, particularly those onprivate land, may become unsuitable forwaterbirds due to changes in land usepractices. Similarly, additional sites thatare not currently suitable for waterbirdsmay become so following restorationefforts. The implementation of recoveryactions for Hawaiian waterbirds must beflexible and often depends onopportunities provided by interestedparties. The recovery criteria for these

species thus also should be flexible, sothat future changes in land use andunexpected opportunities for recoverycan be accommodated. Therefore, itmay be possible to substitute otherwetlands for the supporting wetlands, aslong as they provide a similar amount ofhabitat that can be expected to support asimilar number of birds. We will usethe best available information andupdate the supporting wetland list asnecessary. Appendix C provides a morecomprehensive list of wetlands on eachisland.

For core wetlands it will be difficultto substitute an alternate site thatprovides the same function because theyare among the largest wetlands andsupport the greatest abundance of eachspecies. An exception among the corewetlands may be the Playa Lakes onNiìhau, which in some years provideseasonally important habitat for largenumbers of stilts and coots, but arelocated on private land where it may bedifficult to ensure protection of thehabitat. If similar habitat can berestored in a supporting location, suchas the M~n~ Plain, which once containedextensive seasonal wetlands, then thatsite could be substituted for the PlayaLakes as a core wetland.

Core and supporting wetlands includeFederal, State, and private lands. Mostsites are natural wetlands, but some areof human origin, such as aquacultureponds, agricultural areas, sewagetreatment ponds, and reservoirs. Whilethese sites generally are not managed forwaterbirds, resource management andregulatory agencies should seek thedevelopment of cooperative agreements,


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Table 6. Core and supporting wetlands on Kauaì (K) and Niìhau (N) identified forprotection and management in order to recover the Hawaiian duck, Hawaiian coot,Hawaiian common moorhen, and Hawaiian stilt.

Island Wetland Status Ownership

N Playa Lakes Core Private

K Hanalei NWR Core USFWS1

K Hul‘ìa NWR Core USFWS1

K Kawaièle Waterbird Sanctuary Core HDLNR2

K Lumahaì Wetlands Core Private

K Hanalei Taro Fields and River Supporting Private/State

K Hanap‘p‘ Salt Ponds Supporting Private/HDLNR2

K M~n~ Base Wetlands Supporting Private/HDLNR2

K M~n~ Wetlands Supporting Private/State

K Æpaekaà Marsh Supporting Private/HDLNR2

K Smith’s Tropical Paradise Supporting Private/State

K Wailua River Bottoms Supporting Private/State

K Waimea River System Supporting Private/State

K Wainiha Valley Taro Fields and River Supporting Private/County

K Wait~ Reservoir Supporting Private

1USFWS = U.S. Fish and Wildlife Service2 HDLNR = Hawaiì Department of Land and Natural Resources


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Table 7. Core and supporting wetlands on Oàhu identified for protection andmanagement in order to recover the Hawaiian duck, Hawaiian coot, Hawaiiancommon moorhen, and Hawaiian stilt.

Wetland Status Ownership

James Campbell National Wildlife Refuge Core USFWS1

Kawainui Marsh Core HDLNR2

Nu'upia Ponds Core MCBH3

Pearl Harbor National Wildlife Refuge Core USFWS1

Pouhala Marsh Waterbird Sanctuary Core HDLNR2

Kahuku aquaculture farms Supporting Private

Kuilima (Turtle Bay) Sewage Treatment Plant Supporting Private

Halei'wa Lotus Fields Supporting Private/County

H~m~kua Marsh Wildlife Sanctuary Supporting HDLNR2

He'eia Marsh Supporting HDLNR2

Ka'elepulu Pond Supporting Private

L~'ie Wetlands Supporting Private

Niuli'i Ponds (RTF Lualualei) Supporting USN4 /USFWS1

Punahoòlapa Marsh Supporting Private

Ùkoà Marsh Supporting Private

Waialua Lotus Fields Supporting Private

Waiheè Marsh Supporting Private

1USFWS = U.S. Fish and Wildlife Service2 HDLNR = Hawaiì Department of Land and Natural Resources3 MCBH = Marine Corps Base Hawaiì4 USN = U.S. Navy


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Table 8. Core and supporting wetlands on Maui (M), Molokaì (Mo), and L~naì (L)identified for protection and management in order to recover the Hawaiian duck,Hawaiian coot, Hawaiian common moorhen, and Hawaiian stilt.

Island Wetland Status Ownership

M Kanah~ Pond Wildlife Sanctuary Core HDLNR2

M Ke~lia Pond National Wildlife Refuge Core USFWS1

M Keànae Point Supporting State

M Waiheè Preserve (coastal dunes andwetlands)

Supporting Private

Mo Kakahaià National Wildlife Refuge Core USFWS1

Mo Kaunakakai Sewage Treatment Pond Supporting County

Mo Kualapuù Reservoir Supporting State

Mo `Æhiàpilo Wetland Supporting County

Mo Paialoa Fish Pond Supporting Private

L L~naì Sewage Treament Ponds Supporting County

1USFWS = U.S. Fish and Wildlife Service2 HDLNR = Hawaiì Department of Land and Natural Resources


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Table 9. Core and supporting wetlands on Hawaiì island identified for protection andmanagement in order to recover the Hawaiian duck, Hawaiian coot, Hawaiiancommon moorhen, and Hawaiian stilt.

Wetland Status Ownership

Àimakap~/Koloko Pond Core NPS5

Loko Waka Pond Core Private/State

Waiakea Pond Core State/County

Keànae Pond (Keaàu) Supporting Private

Kohala Stock Ponds Supporting Private

Mauna Kea Stock Ponds Supporting Private

Kona (Kealakehe) Sewage Treatment Plant Supporting County

`Æpaeùla Pond Supporting Private

Parker Ranch Ponds Supporting Private

Waimanu Valley Supporting County

Waipiò Valley Supporting County/Private

5 NPS = National Park Service

Habitat Conservation Plans, Safe HarborAgreements, conservation easements, orother protective measures to restore,enhance, or create wetland sites thatprovide important habitat for waterbirds. Such actions may provide long-termprotection of these sites or encouragehabitat improvements.

The distribution of core andsupporting habitat allows for multiplebreeding localities on the mainHawaiian islands within each species’historical distribution. Such adistribution should enhance recovery byminimizing the impact of randomenvironmental events and catastrophesthat can adversely affect the viability of

these endangered waterbirds (Meffe andCarroll 1996; Shaffer 1996).

Actions identified in this plan toprotect and manage both core andsupporting wetlands include efforts todirectly address many of the threatsidentified for the endangered waterbirds,as detailed below. Some of therecommended actions are site-specific,such as establishing protected landstatus and writing management plans,while other actions, such as populationmonitoring, assessing reproductivesuccess, and increasing publicawareness should be implemented on astatewide basis. The basic steps detailedin this recovery plan are as follows:


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1) Protect and manage core andsupporting wetland habitats in orderto maximize productivity andsurvival of endangered waterbirds. This management would include thefollowing actions: develop writtenmanagement plans; secure watersources; manage water levels;manage vegetation; controlpredation; monitor waterbirdpopulations and reproductivesuccess; remove the threat ofmallard-Hawaiian duckhybridization; minimize humandisturbance; and monitor andcontrol avian diseases andenvironmental contaminants (Tables10 and 11, pages 93 and 95). Someof these wetland habitat areasalready have protected status butneed to be more actively managed.

2) Conduct research to betterunderstand factors limitingHawaiian waterbird populationnumbers, refine recovery objectives,and improve managementtechniques.

3) Establish a Hawaiian duckpopulation on one additional islandand moorhen populations on twoadditional islands.

4) Plan and implement an educationprogram to increase landowner andland manager knowledge ofwaterbird needs and increase publicsupport for waterbird recovery.

5) Reevaluate recovery objectives asadditional information becomesavailable.

The key to the success of thisgeneral recovery strategy will be theformation of productive partnershipsamong Federal, State and local agencies,private organizations, and individuals. Partnerships have been instrumental inachieving past conservation efforts andare essential to protect and manageexisting wetlands. Such partnershipsalso result in greater community supportto insure long-term wetland andwaterbird protection. Each of the basicsteps identified above will succeed onlywith the active participation of a varietyof entities.

B. GOAL AND OBJECTIVES

The ultimate goal of the recoveryprogram is to restore and maintainmultiple self-sustaining populations ofthese Hawaiian waterbirds within theirhistorical ranges, which will allow themto be reclassified to threatened statusand eventually removed from theFederal list of endangered species.

The recovery of the endangeredwaterbirds focuses on the followingobjectives:

1) increasing population numbers tostatewide baseline levels;

2) establishing multiple, self-sustainingbreeding populations throughouteach species’ historical range;

3) establishing and protecting anetwork of wetlands that aremanaged as habitat suitable forwaterbirds, including themaintenance of appropriatehydrological conditions and control


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Box 1. Definitions according to section 3 of the

Endangered Species Act.

Endangered SpeciesAny species that is in danger ofextinction throughout all or a significantportion of its range.

Threatened SpeciesAny species that is likely to becomeendangered within the foreseeable futurethroughout all or a significant portion ofits range.

of invasive nonnativeplants;

4) for all four species, eliminating orcontrolling the threats posed byintroduced predators, humandisturbance, avian diseases, andcontaminants; and

5) for the Hawaiian duck, removing thethreat of hybridization with feralmallards.

C. RECOVERY CRITERIA

Downlisting or delisting iswarranted when a listed species nolonger meets the definition of threatenedor endangered under the EndangeredSpecies Act (Box 1). We set recoverycriteria to serve as objective, measurableguidelines to assist us in determiningwhen a species has recovered to thepoint that the protections afforded by theEndangered Species Act are no longernecessary. However, the actual changein listing status is not solely dependentupon achieving the recovery criteria setforth in a recovery plan; it requires aformal rulemaking process based uponan analysis of the same five factorsconsidered in the listing of a species (seepage 44). The recovery criteriapresented in this recovery plan thusrepresent our best assessment of theconditions that would most likely resultin a determination that downlisting ordelisting of each of the four Hawaiianwaterbirds is warranted as the outcomeof a formal five factor analysis in asubsequent regulatory rulemaking.

The successful elimination orcontrol of the threats that originally ledto the need for protection under theEndangered Species Act is a keycomponent of recovery. In this recoveryplan, hybridization with feral mallards isa threat unique to the Hawaiian duck,and this threat is therefore addressedseparately for this species. Otheridentified threats to the four endangeredwaterbirds, including introducedpredators, altered hydrology, nonnativeplants, avian disease, and contaminants,are specifically addressed by themanagement actions recommended inthis plan (see Narrative Outline ofRecovery Actions, page 79) and areincorporated in the Recovery Criteriathrough Criteria 1 and 2 for eachspecies, which call for the protectionand management of wetlands inaccordance with the managementpractices outlined in this recovery plan.


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1. Downlisting Criteria

To consider downlisting the fourspecies to threatened status, thefollowing criteria should be met:

(a) Hawaiian Duck downlistingcriteria

Criterion 1. All core wetlands listed inTable 10 on the islands of Kauaì,Oàhu, Maui, and Hawaiì are protectedand managed in accordance with themanagement practices outlined in thisrecovery plan;

Criterion 2. Of the supporting wetlandslisted in Table 11 on the islands ofKauaì, Oàhu, Maui, and Hawaiì, atleast 25 percent are protected andmanaged in accordance with themanagement practices outlined in thisrecovery plan;

Criterion 3. The statewide Hawaiianduck population shows a stable orincreasing trend at a number greaterthan 2,000 birds for at least 5consecutive years;

Criterion 4. There are multiple self-sustaining breeding populations, withpopulations present on Kauaì, Oàhu,Maui, and Hawaiì; and

Criterion 5. The threat of hybridizationwith feral mallards is removed from allislands.

(b) Hawaiian Coot downlisting criteria

Criterion 1. All core wetlands listed inTable 10 on the islands of

Kauaì/Niìhau, Oàhu, Hawaiì, andMaui/Molokaì, are protected andmanaged in accordance with themanagement practices outlined in thisrecovery plan;

Criterion 2: Of the supporting wetlandslisted in Table 11 on the islands ofKauaì/Niìhau, Oàhu, Hawaiì, andMaui/Molokaì/L~naì, 25 percent areprotected and managed in accordancewith the management practices outlinedin this recovery plan;

Criterion 3: The statewide cootpopulation shows a stable or increasingtrend at a number greater than 2,000birds for at least 5 consecutive years;and

Criterion 4: There are multiple self-sustaining breeding populations, withpopulations present on Kauaì/Niìhau,Oàhu, Hawaiì, and Maui/Molokaì/L~naì.

(c) Hawaiian Common Moorhendownlisting criteria

Criterion 1: All core wetlands listed inTable 10 on the islands of Kauaì andOàhu are protected and managed inaccordance with the managementpractices outlined in this recovery plan;

Criterion 2: Of the supporting wetlandslisted in Table 11 on the islands ofKauaì and Oàhu, 25 percent areprotected and managed in accordancewith the management practices outlinedin this recovery plan;

Criterion 3: The statewide moorhenpopulation shows a stable or increasing


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trend at a number greater than 2,000birds for at least 5 consecutive years;and

Criterion 4: There are multiple self-sustaining breeding populations, withpopulations present on Kauaì andOàhu, and on Maui/Molokaì and/orHawaiì.

(d) Hawaiian Stilt downlistingcriteria

Criterion 1: All core wetlands listed inTable 10 on the islands ofKauaì/Niìhau, Oàhu, Hawaiì, andMaui/Molokaì, are protected andmanaged in accordance with themanagement practices outlined in thisrecovery plan;


Criterion 3: The statewide stiltpopulation shows a stable or increasingtrend at a number greater than 2,000birds for at least 5 consecutive years;and

Criterion 4: There are multiple self-sustaining breeding populations,including populations onKauaì/Niìhau, Oàhu, Hawaiì, andMaui/Molokaì/L~naì.

2. Delisting Criteria

To consider delisting the fourspecies, the following criteria must bemet:

(a) Hawaiian Duck delistingcriteria

Criterion 1: All core wetlands listed inTable 10 on the islands of Kauaì,Oàhu, Maui, and Hawaiì are protectedand managed in accordance with themanagement practices outlined in thisrecovery plan;

Criterion 2: Of the supporting wetlandslisted in Table 11 on the islands ofKauaì, Oàhu, Maui, and Hawaiì, 75percent are protected and managed inaccordance with the managementpractices outlined in this recovery plan;

Criterion 3: The statewide Hawaiianduck population shows a stable orincreasing trend at a number greaterthan 2,000 birds for at least 10consecutive years;

Criterion 4: There are multiple self-sustaining breeding populations, withpopulations present on Kauaì, Oàhu,Maui, and Hawaiì; and

Criterion 5: The threat of hybridizationwith feral mallards is removed from allislands.


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(b) Hawaiian Coot delistingcriteria



Criterion 3: The statewide cootpopulation shows a stable or increasingtrend at a number greater than 2,000birds for at least 10 consecutive years;and


(c) Hawaiian Common Moorhendelisting criteria

Criterion 1: All core wetlands listed inTable 10 on the islands of Kauaì andOàhu are protected and managed inaccordance with the managementpractices outlined in this recovery plan;

Criterion 2: Of the supporting wetlandslisted in Table 11 on the islands ofKauaì and Oàhu, 75 percent areprotected and managed in accordance

with the management practices outlinedin this recovery plan;

Criterion 3: The statewide moorhenpopulation shows a stable or increasingtrend at a number greater than 2,000birds for at least 10 consecutive years;and

Criterion 4: There are multiple self-sustaining breeding populations, withpopulations present on Kauaì, Oàhu,Hawaiì, and Maui/Molokaì.

(d) Hawaiian Stilt delistingcriteria



Criterion 3: The statewide stiltpopulation shows a stable or increasingtrend at a number greater than 2,000birds for at least 10 consecutive years;and



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D. STEP-DOWN OUTLINE OF RECOVERY ACTIONS

1. Protect (secure from development) and manage all core (100%) and supportingwetlands (25% for downlisting and 75% for delisting) listed in Tables 10 and 11(pages 93 and 95).1.1 Develop management plans for core and supporting wetlands.1.2 Coordinate management of core and supporting wetlands with other agencies

and organizations.1.3 Implement management plans for core and supporting wetlands.

1.3.1 Secure water sources and manage water levels to maximize nestingsuccess, brood survival, food availability, and recruitment of waterbirds.

1.3.2 Manage vegetation to maximize nesting success, brood survival, foodavailability, and recruitment of waterbirds.

1.3.2.1 Encourage desirable plant species.1.3.2.2 Control undesirable plant species.

1.3.2.3 Prevent introduction of invasive nonnative plants.1.3.3 Eliminate or reduce and monitor predator populations.

1.3.3.1 Prevent predator access.1.3.3.2 Control mongooses. 1.3.3.3 Control feral cats.1.3.3.4 Control feral dogs.1.3.3.5 Control rats.1.3.3.6 Control cattle egrets.1.3.3.7 Control tilapia.1.3.3.8 Control bullfrogs.

1.3.4 Prevent introduction of new nonnative predators, such as the browntreesnake (Boiga irregularis).

1.3.5 Minimize human disturbance to waterbirds and their habitats.1.3.5.1 Assess and if necessary prevent intentional or accidental

shooting of waterbirds.1.3.5.2 Control human access to waterbird habitats during breeding

season.1.3.5.3 Resolve conflicts from actual or perceived depredation of

aquaculture or agriculture products by waterbirds.1.3.5.4 Minimize influence of urban encroachment.

1.3.6 Monitor and control avian disease.1.3.6.1 Monitor waterbird populations to detect disease outbreaks as

soon as possible.1.3.6.2 Take immediate action to restrict the spread of disease outbreaks.

1.3.7 Minimize contamination of waterbird habitat by toxic substances.1.3.7.1 Monitor water quality.1.3.7.2 Restrict introduction of contaminants into wetland systems.1.3.7.3 Assess nutrient levels and other parameters that influence core

and supporting wetland productivity for waterbirds.


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1.4 Monitor all populations of endangered waterbirds.1.4.1 Continue standardized, biannual, statewide surveys for all endangered

waterbirds.1.4.2 Continue regular, standardized surveys on core and supporting

wetlands.1.4.3 Develop improved survey techniques for the Hawaiian duck and

Hawaiian common moorhen.1.4.4 Monitor reproductive success on core and supporting

wetlands.1.4.5 Monitor aquatic invertebrate prey species used by waterbirds and fish to

determine whether they compete with waterbirds for aquaticinvertebrates.

2. Remove the threat of mallard-Hawaiian duck hybridization on all islands whereHawaiian ducks occur and establish a self-sustaining population of Hawaiian duckson Maui and/or Molokaì.2.1 Conduct a public information and education program regarding the mallard-

Hawaiian duck interbreeding problem and the need for the removal program.2.2 Develop methods for differentiating between Hawaiian ducks and mallard-

Hawaiian duck hybrids.2.3 Implement a statewide program to humanely remove feral mallards and

mallard-Hawaiian duck hybrids.2.4 Ensure new stocks of mallards and closely related ducks are not brought into

the state.2.5 Establish a self-sustaining population of Hawaiian ducks on Maui and/or

Molokaì.2.5.1 Identify sites for reintroduction of the Hawaiian duck on Maui and

Molokaì.2.5.2 Investigate the pros and cons of captive propagation versus

translocation for establishing additional Hawaiian duck populations anddevelop a reintroduction plan that includes the preferred method.

2.5.3 Reintroduce either captive-bred or translocated Hawaiian ducks toprotected and managed sites on Maui and Molokaì and monitor theirsurvival, dispersal, and reproduction.

3. Establish a self-sustaining population of Hawaiian common moorhen on the island ofHawaiì and either Maui or Molokaì.3.1 Conduct thorough surveys of wetland areas on Maui, Molokaì, and Hawaiì

to confirm that a moorhen population does not already exist.3.2 If a population of moorhen is found on Maui, Molokaì, or Hawaiì, protect

and manage its wetland habitat.3.3 If no population of moorhen is found on Maui, Molokaì, or Hawaiì, evaluate

potential reintroduction sites. 3.4 Investigate the pros and cons of captive propagation versus translocation for

establishing additional moorhen populations and develop a reintroduction planthat includes the preferred method.


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3.5 Reintroduce Hawaiian common moorhens to a protected and managed site onHawaiì and either Maui or Molokaì and monitor their survival, dispersal,and reproduction.

4. Conduct research to better understand population biology and limiting factors,evaluate recovery objectives, and improve management techniques.4.1 Increase understanding of Hawaiian waterbird population limiting factors.

4.1.1 Investigate the effects of different predators on endangered waterbirds. 4.1.2 Research improved predator control methods.4.1.3 Research improved methods to control nonnative plants and restoration

of native plants.4.2 Conduct research to better understand Hawaiian waterbird population biology

and recovery needs. 4.2.1 Analyze existing survey data and estimate current population size and

population trends.4.2.2 Determine carrying capacity of wetland habitats.4.2.3 Estimate reproductive parameters.4.2.4 Estimate mortality rates.4.2.5 Research movement of adults and natal dispersal.4.2.6 Determine the sex and age structure of populations.4.2.7 Investigate genetic population structure and potential inbreeding

depression.4.2.8 Develop population viability analyses for the Hawaiian duck, coot, and

moorhen.4.3 Research Hawaiian waterbird habitat needs and habitat manipulation.

5. Plan and implement a public information and education program to increase publicawareness and support for waterbird recovery.5.1 Prepare and distribute television and radio spots, written information, slide

programs, videos, films, posters, and displays.5.2 Coordinate with the Hawaiì Department of Education and private schools to

incorporate wetland and waterbird information into school curricula.5.3 Develop and maintain interpretive displays of endangered waterbirds and

wetlands.


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E. NARRATIVE OUTLINE OF RECOVERY ACTIONS

1. Protect (secure from development) and manage all core (100%) and supportingwetlands (25% for downlisting and 75% for delisting) listed in Tables 10 and 11(pages 93 and 95).A network of protected and managed wetland habitats is the key element in therecovery strategy for all four taxa. Loss of habitat has been and continues to be aprimary threat, thus maintenance of suitable habitat distributed over all the mainislands is imperative for recovery of these waterbirds. Most core wetlands areprotected except the Playa Lakes (Niìhau), Lumahaì Wetlands (Kauaì), LokoWaka Ponds (Hawaiì), and Wai~kea Pond (Hawaiì). Agreements with thelandowners should be developed to insure protection of these wetlands. Some ofthese areas are sufficiently managed, but most need increased levels of managementto maximize waterbird production and survivability.

Supporting wetlands are additional areas that provide habitat important for smallerwaterbird populations or that provide habitat needed seasonally by segments of thewaterbird population during part of their life cycle. Protection and management ofthese or similar wetlands is required to recover Hawaii`s waterbirds, but there is roomfor some flexibility in which sites must be managed, and it is possible that other sitesmay fulfill the same needs as those listed here (Appendix C). Tools available towork with private landowners to provide habitat management and protection includeHabitat Conservation Plans, Safe Harbor Agreements, Partners for Fish and Wildlifeand Coastal programs, and conservation easements.

1.1 Develop management plans for core and supporting wetlands.Management of the core and supporting wetlands is required to realize theirfull potential for providing waterbird nesting and/or feeding habitat.Management plans should be developed for core and supporting wetlands andactions to be implemented on these habitats will include, but are not limitedto, the recommended recovery actions in Tables 10 and 11.

1.2 Coordinate management of core and supporting wetlands with otheragencies and organizations.Managers charged with the stewardship of refuges and sanctuaries havedeveloped numerous methods of habitat management. These techniques varyamong sites. Interagency management workshops, such as the Wetland andPredator Control Workshops organized by The Wildlife Society and theHawaiì Department of Land and Natural Resources, or other forums forexchanging information have been held and should continue to be regularlyconducted in Hawaiì. These meetings provide a professional forum for thepresentation of management methodology practiced in Hawaiì and allowmanagers to present published and unpublished research results, develop newmethods, and find solutions to shared management problems. A statewide


80

approach to wetland stewardship is important for successful management ofcore and supporting wetlands.

1.3 Implement management plans for core and supporting wetlands.Wetland habitats in Hawaiì, including wildlife sanctuaries and refuges, havebeen altered or influenced to a varying extent by a number of factors. Providing these areas with the habitat components that allow waterbirds tosurvive and reproduce successfully requires active management. The stepsnecessary for enhancing habitat for Hawaiì’s endangered waterbirds areoutlined below. A number of these are already being implemented onprotected wetland areas.

1.3.1 Secure water sources and manage water levels to maximize nestingsuccess, brood survival, food availability, and recruitment ofwaterbirds.Hydrology is key to ensuring the suitability of wetland habitat for theseendangered waterbirds. An adequate water source must be ensured, andwater levels must be managed so as to enhance productivity of wetlandfood sources and to provide suitable vegetative cover.

1.3.2 Manage vegetation to maximize nesting success, brood survival,food availability, and recruitment of waterbirds.The composition and distribution of vegetation in a wetland ecosystemdetermines the habitat's value for waterbirds. Most of Hawaiì’swetlands have been extensively altered such that vegetationmanagement is required to provide habitat for waterbirds.

1.3.2.1 Encourage desirable plant species.Certain types of vegetation provide better feeding and nestingconditions for waterbirds. Habitat management should aim todevelop the optimum distribution and density of these species,with an emphasis on enhancing native species. Desirable nativeplant species include, but are not limited to, Bacopa monnieri(àeàe, water hyssop); Bolboschoenus maritimus (kaluha,bulrush); Cyperus javanicus C. laevigatus, C. polystachyos, andC. trachysanthos (ahuàwa, makaloa, umbrella sedge);Eleocharis obtusa (kohekohe, spikerush); Ludwigia octovalvis(primrose willow); Ruppia maritima (ditchgrass, widgeongrass);Schoenoplecus juncoides and S. lacustris (àkaàkai); andSesuvium portulacastrum (àkulikuli, sea purslane).

In some cases naturalized nonnative plants can provide importanthabitat components for waterbirds as well, serving as a source offood, cover, nesting material, and habitat for invertebrate prey.


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Nonnative plants that serve these functions should not beeradicated before a suitable native plant species is identified thatwould provide equivalent resources. Nonnative plants that mayprovide beneficial resources for waterbirds include Cyperusdifformis (variable flatsedge); Echinochloa spp. (cockspur,barnyard grass); Eleocharis geniculata (spikesedge);Fimbristylis ferruginea (West Indian fimbry); Lemna spp.(duckweed); Leptochloa uninervia (sprangletop); Paspalumdistichum (knotgrass); and Typha spp. (cat-tails).

1.3.2.2 Control undesirable plant species.Undesirable plants, mainly introduced species such asBrachiaria mutica (California grass), Batis maritima(pickleweed), Eichornia crassipes (water hyacinth), Plucheaindica (Indian fleabane), and Rhizophora mangle (redmangrove), make wetlands less useful or unusable forwaterbirds. These plants should be eliminated, where feasible,or controlled. In many cases, water level management can beused to control noxious species. Some indigenous species mightpose a problem as they overgrow wetlands and result inmonocultures. Control methods that do not introduceenvironmental contaminants and that can be sustained over thelong-term should be employed.

1.3.2.3 Prevent introduction of invasive nonnative plants.Nonnative plants, particularly invasive species, can decreasewetland suitability for waterbirds. Measures should be taken toprevent accidental introduction of nonnative plants by people orequipment used in the management of wetlands and to preventthese plants from becoming established in wetland habitats. Forexample, equipment used on wetlands should be thoroughlycleaned before being used at a site.

1.3.3 Eliminate or reduce and monitor predator populations.

Predation is a major cause of waterbird mortality and nest failure. Introduced mammals such as mongooses, cats, dogs, and rats are theprimary predators, but depredation by birds and bullfrogs has also beendocumented. Adult waterbirds are occasionally taken, but mostdepredation is of eggs and young. Long-term predator management atnesting sites is needed and may be more effective when control methodsare used in conjunction with exclusion devices such as fences.


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1.3.3.1 Prevent predator access.One means of controlling predators is preventing their access tonesting habitat. This can be accomplished by the use of barriers,moats, or fences. Moats can be constructed around nestinghabitat if sedimentation and vegetation are adequately controlled. Where appropriate and feasible, barriers and/or fences should beinstalled around important breeding sites to exclude as manyspecies of predators as possible.

1.3.3.2 Control mongooses.Mongooses are thought to be the most serious predator ofHawaiì’s waterbirds in many areas. Removal of mongooses hasbeen proven to increase waterbird reproduction and should beactively pursued using trapping and/or toxicants. Moats can beconstructed around nesting islands if sedimentation andvegetation can be adequately controlled.

1.3.3.3 Control feral cats.Feral cats are known to be predators of waterbirds and should becontrolled. Feral cat feeding stations near waterbird habitatshould be removed or relocated. Public education about thedetrimental effects of feral cats is also important.

1.3.3.4 Control feral dogs.Dogs are known to kill waterbirds and should be removed. Dogsoften can be effectively excluded by fences.

1.3.3.5 Control rats.Rats have been known to prey on waterbird chicks and eggs. The importance of rat predation should be assessed and controlmeasures implemented as necessary.

1.3.3.6 Control cattle egrets.Predation and competition for food resources by cattle egrets ispoorly understood in Hawaiì, but we do know that cattle egretsprey on stilt chicks. Modified habitats and exposed nesting areasmake young waterbirds more vulnerable to predation. Theseareas should be identified and improved. Control of cattle egretsin rookeries near, or in, refuges has proven effective and shouldbe continued.

1.3.3.7 Control tilapia.Tilapia modify the bottom of wetlands by creating circular nestsand are suspected of depleting the invertebrate prey base used by


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endangered waterbirds, thereby degrading waterbird feedinghabitats. Tilapia should be controlled, possibly by manipulatingwater levels.

1.3.3.8 Control bullfrogs.Bullfrogs are known to prey on juvenile Hawaiian ducks andstilts, and were identified as an important predator on radio-tracked stilt chicks at James Campbell National Wildlife Refuge(Eijzenga 2003). It may be possible to control bullfrogs bydirect removal, or by strategic manipulation of water levels.

1.3.4 Prevent introduction of new nonnative predators, such as thebrown treesnake (Boiga irregularis). Nonnative predators are causing severe problems for native waterbirds. Introductions of new predators, such as the brown treesnake, must beprevented in the entire state. Special attention is needed to prevent theestablishment of mongooses on Kauaì, L~naì, and Niìhau.

1.3.5 Minimize human disturbance to waterbirds and their habitats.Disturbance or loss of adult and young waterbirds is occasionallyattributed to people. Although such losses are usually restricted toisolated incidents, measures should be taken to minimize this threat.

1.3.5.1 Assess and if necessary prevent intentional or accidentalshooting of waterbirds.The occurrence of shooting of waterbirds should be assessed andcontrol measures taken as necessary to prevent such eventsthrough law enforcement and/or public education.

1.3.5.2 Control human access to waterbird habitats during breeding season.Certain habitats and birds are more sensitive to humandisturbance, especially during the breeding season. Restricting human access to sensitive habitat areas during certain times ofthe year may be needed.

1.3.5.3 Resolve conflicts from actual or perceived depredation onaquaculture or agriculture products by waterbirds.Some waterbird habitat is also used for agriculture andaquaculture. This can result in conflicts due to actual and/orperceived depredation problems attributed to endangeredwaterbirds. Wildlife agencies need to respond to potentialproblems associated with waterbirds and minimize conflicts. Problems not associated with waterbirds can be explained and


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solutions to problems associated with waterbirds can be soughtbefore birds or nests are harmed. Open communication betweenagricultural and waterbird managers is necessary to minimizeconflicts.

1.3.5.4 Minimize the influence of urban encroachment.Urban encroachment is a significant threat to wetland areas inHawaiì. Urban encroachment has increased because of therecent shift in land use from agriculture to housingdevelopments. Issues such as predator control, water quality,and harassment are magnified in an urban setting. Refuges thatwere once surrounded by cane fields are now surrounded byhousing tracts or resort developments. The establishment ofbuffer lands around protected wetlands through cooperativeagreements or other measures is critical to the protection of thesehabitats. Buffer lands can also provide corridors betweenwetland refuges within a large complex.

1.3.6 Monitor and control avian disease.Waterbirds and their habitat should be monitored for potential diseaseproblems. When avian diseases are detected, control measures must beemployed rapidly. Diseases that may affect endangered waterbirdsinclude, but may not be limited to, avian botulism, cholera, malaria,pox, and West Nile virus.

1.3.6.1 Monitor waterbird populations to detect disease outbreaks assoon as possible.Disease monitoring should be a part of wetland areamanagement. A disease monitoring protocol should bedeveloped, made available for wide use, and incorporated intomanagement plans. Wildlife health professionals should beconsulted to develop monitoring techniques.

1.3.6.2 Take immediate action to restrict the spread of diseaseoutbreaks.When a disease outbreak is identified, managers need to takeimmediate action to restrict the disease's spread and severity. Disease response protocols should be developed andincorporated into management plans.

1.3.7 Minimize contamination of waterbird habitat by toxic substances.Contamination of wetlands with toxic substances is a potential threat. Because waterbirds are often concentrated in small areas, the localizedcontamination of water or food can affect a large number of birds.


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1.3.7.1 Monitor water quality.To minimize exposure of waterbirds to contaminants,environmental contaminant monitoring should be incorporatedinto management plans.

1.3.7.2 Restrict introduction of contaminants into wetland systems.To minimize potential impacts to waterbirds, the introduction ofchemicals to wetland areas, either directly or via water supplies,should be restricted as much as possible.

1.3.7.3 Assess nutrient levels and other parameters that influencecore and supporting wetland productivity for waterbirds.Wetland productivity for waterbirds varies annually. Measuringnutrient levels, food availability, and other parameters thatinfluence productivity of wetlands for waterbirds will enhanceour understanding of waterbird populations.

1.4 Monitor all populations of endangered waterbirds.Monitoring populations of waterbirds is important for assessing the success ofmanagement activities.

1.4.1 Continue standardized, biannual, statewide surveys for allwaterbirds.The biannual statewide surveys provide valuable information forgauging the status of endangered waterbirds, particularly Hawaiiancoots and stilts. These surveys should be continued to provide a long-term data set for examining population trends.

1.4.2 Continue regular, standardized surveys on core and supportingwetlands.Regular, standardized surveys of core and supporting wetlands willprovide valuable information on short-term population fluctuations andresponses to management techniques. Monthly counts at core andsupporting wetlands that include the evaluation of habitat parameterswill provide valuable information on wetland biology.

1.4.3 Develop improved survey techniques for the Hawaiian duck andHawaiian common moorhen.Existing survey techniques are adequate for assessing Hawaiian cootand stilt populations, but improved methods are needed to accuratelysurvey Hawaiian ducks and Hawaiian common moorhens. Because oftheir secretive behavior and use of densely vegetated and montanestream habitats, these birds are difficult to accurately survey.


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1.4.4 Monitor reproductive success on core and supporting wetlands.Surveys are needed to determine the reproductive success of endangeredwaterbirds. Hawaiian stilt recruitment survey techniques have alreadybeen developed, but methods for monitoring the reproductive success ofthe other species should be developed and implemented on core andsupporting wetlands.

1.4.5 Monitor aquatic invertebrate prey species used by waterbirds andfish to determine whether they compete with waterbirds for aquaticinvertebrates.Monitoring seasonal densities of aquatic invertebrates that occur in thediets of waterbirds may identify periods when food sources are scarce. Fish should also be monitored to determine if they are competitors ofaquatic invertebrate prey used by waterbirds. If nonnative fish such astilapia are determined to be competitors, control measures and/oreradication of fish should be developed and implemented.

2. Remove the threat of mallard-Hawaiian duck hybridization on all islands whereHawaiian ducks occur and establish a self-sustaining population of Hawaiianducks on Maui and/or Molokaì.Hybridization between Hawaiian ducks and mallards has resulted in a largepopulation of hybrids and a scarcity of pure Hawaiian ducks on the island of Oàhu. This threat also occurs on Kauaì, Maui, and Hawaiì, although to a lesser extent. Hybridization of the Hawaiian duck with mallards or other related waterfowl shouldbe prevented.

Self-sustaining Hawaiian duck populations should be established on Maui and/orMolokaì. Although a small population (fewer than 15 individuals) of Hawaiianducks exist on Maui (F. Duvall, pers. comm. 2004), augmentation may be needed toincrease the likelihood of its sustainability.

2.1 Conduct a public information and awareness program regarding themallard-Hawaiian duck interbreeding problem and the need for a feraland hybrid duck removal program.Eliminating hybridization will be controversial unless the public becomesaware of its importance. The public may be more supportive of programs toremove mallards, other closely related feral ducks, and mallard-Hawaiianduck hybrids from the islands if the program’s role in preserving the nativespecies is better understood.

2.2 Develop methods for differentiating between Hawaiian ducks andmallard-Hawaiian duck hybrids. Methods for identifying mallard-Hawaiian duck hybrids need to be developedto insure that the correct birds are removed from the population. The


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development of such identification criteria will require the simultaneouscollection of genetic and morphological data. Genetic information can beused to confirm field identification of birds, thus protecting Hawaiian ducks. An identification guide outlining physical characteristics unique to pureHawaiian ducks is currently under development to assist in differentiatingbetween Hawaiian ducks and hybrids (A. Engilis, pers. comm. 2003).

2.3 Implement a statewide program to humanely remove feral mallards andmallard-Hawaiian duck hybrids.A Hawaiian duck recovery implementation group that includes variousresource agencies and researchers was recently established to address thisproblem. The group is working on developing a comprehensive statewideapproach to the mallard-Hawaiian duck hybridization problem. Efforts toremove mallards and related waterfowl should be accomplished throughapproved duck trapping techniques and other humane methods.

2.4 Ensure new stocks of mallards and closely related ducks are not broughtinto the state.Strict control over the entry of additional domesticated mallards or closelyrelated ducks into Hawaiì should be enacted. Coordination with the HawaiìDepartment of Agriculture will be necessary to maintain or improveimportation controls.

2.5 Establish a self-sustaining population of Hawaiian ducks on Maui and/orMolokaì.Techniques for breeding the Hawaiian duck in captivity have been developed;however, translocation might also prove to be a useful method ofreestablishing or augmenting populations.

2.5.1 Identify sites for reintroduction of the Hawaiian duck on Maui andMolokaì.Core wetlands that are protected and managed for waterbirds (Table 10)should be considered first as sites for Hawaiian duck reintroduction. Ifnone of these areas are suitable, supporting wetlands (Table 11) shouldbe considered before consideration of other areas (Appendix C).

2.5.2 Investigate the pros and cons of captive propagation versustranslocation for establishing additional Hawaiian duck populationsand develop a reintroduction plan that includes the preferredmethod.The pros and cons of captive propagation versus translocation should beinvestigated to determine which method is likely to be more successfuland efficient for reestablishing a Hawaiian duck population. Areintroduction plan should be developed using the preferred method.


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2.5.3 Reintroduce either captive-bred or translocated Hawaiian ducks toprotected and managed sites on Maui and Molokaì and monitortheir survival, dispersal, and reproduction.Depending on the outcome of Recovery Actions 2.5.1. and 2.5.2, eithercaptive propagation or translocation should be used to reestablish or, inthe case of Maui, augment Hawaiian duck populations at protected andmanaged sites. Newly established Hawaiian duck populations shouldbe monitored to evaluate the success of the reintroduction.

3. Establish a self-sustaining population of Hawaiian common moorhen on Hawaiìand either Maui or Molokaì.Hawaiian common moorhens formerly occurred on all of the main Hawaiian Islandsexcept L~naì and Kahoòlawe, but now occur only on Kauaì and Oàhu. Captivepropagation and release, or translocation of moorhen should be conducted to helprestore this species to its former range.

3.1 Conduct thorough surveys of wetland areas on Maui, Molokaì, andHawaiì to confirm that a moorhen population does not already exist.It is possible that a population of moorhens already exists on the islands ofMaui, Molokaì, or Hawaiì. While this possibility is slim, all likely moorhenhabitat areas should be thoroughly searched, reasons for the disappearance ofmoorhens identified, and the use of core and/or supporting wetlands forpotential reintroduction sites assessed.

3.2 If a population of moorhens is found on Maui, Molokaì, or Hawaiì,protect and manage its wetland habitat.Hawaiian common moorhen populations found on the islands of Maui,Molokaì, or Hawaiì should be increased through habitat protection andmanagement.

3.3 If no population of moorhen is found on Maui, Molokaì, or Hawaiì,potential reintroduction sites should be evaluated. Habitat criteria for the reintroduction of moorhens need to be established. Core and supporting wetlands that are protected and managed should beconsidered first for moorhen reintroduction. If none of these areas aresuitable, additional wetlands (Appendix C) that meet the habitat criteriashould be considered.

3.4 Investigate the pros and cons of captive propagation versus translocationfor establishing additional moorhen populations and develop areintroduction plan that includes the preferred method.Captive propagation and translocation are both useful methods forreintroducing species; however, the method most appropriate in a particularcase depends on the ease of capturing, breeding, and maintaining the species


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in captivity. A reintroduction plan should be developed using the preferredmethod.

3.5 Reintroduce Hawaiian common moorhens to a protected and managedsite on Hawaiì and either Maui or Molokaì and monitor their survival,dispersal, and reproduction.Depending on the outcome of action 3.4, either captive propagation ortranslocation should be used to reestablish a moorhen population on Hawaiìand Maui or Molokaì. Newly established Hawaiian common moorhenpopulations should be monitored to evaluate success of the reintroduction.

4. Conduct research to better understand population biology and limiting factors,evaluate recovery objectives, and improve management techniques.Proper management requires the application of information obtained from research. Many of the successful waterbird management techniques currently in use weredeveloped in response to research findings. Additional research is needed to betterunderstand limiting factors, refine recovery objectives, and improve managementtechniques for Hawaiì’s endangered waterbirds. Adaptive management should beimplemented as management techniques evolve.

4.1 Increase understanding of Hawaiian waterbird population limitingfactors.A better understanding of the factors that limit the recovery of Hawaiì’swaterbirds will allow more effective management techniques to be developed.

4.1.1 Investigate the effects of different predators on endangeredwaterbirds.Waterbirds may be preyed on by a variety of animals, including dogs,cats, mongooses, bullfrogs, black-crowned night-herons, cattle egrets,owls, and possibly others. The relative importance of these predatorsmay differ among sites and waterbird species. The frequency ofpredation, demographic effects, and efficiency of potential controlprograms should be investigated for each predator and at different sites.

4.1.2 Research improved predator control methods.The effectiveness of predator control methods should be evaluated andimproved methods should be developed if possible.

4.1.3 Research improved methods for nonnative plant control andrestoration of native plants.Improved methods for controlling nonnative plants and outplantingnative plants should be developed to improve habitat suitable forwaterbird use.


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4.2 Conduct research to better understand Hawaiian waterbird populationbiology and recovery needs. Scientific information is needed to better understand the population biology ofthese four species. This information can be used to more effectively managethe recovery program and support or modify the recovery criteria for theHawaiian coot, duck, moorhen, and stilt.

4.2.1 Analyze existing survey data and estimate current population sizeand population trends. Surveys to monitor waterbird populations have been conducted formany years. A great deal of information about the size and status ofwaterbird populations can be obtained by careful analysis of this data.

4.2.2 Determine the carrying capacity of wetland habitats.Understanding the limits to the potential population density of thewaterbird species at different types of wetlands will improve our abilityto predict population sizes and whether additional management willallow for an increase in the population size.

4.2.3 Estimate reproductive parameters.Collecting information on the reproductive parameters of all fourwaterbird species will increase our understanding of each species’biology. This research should focus on the following areas: age at firstbreeding, nest site and mate fidelity, length of nesting season, clutchsize, hatching and feeding rates, and nesting attempts per pair.

4.2.4 Estimate mortality rates.Determining the rates and sources of mortality will allow a betterunderstanding of the threats and management needs for each species andfacilitate a determination of the minimum reproductive rates needed toincrease and stabilize populations.

4.2.5 Research on movement of adults and natal dispersal. Investigate the movement patterns of adults and natal dispersal of

juveniles. Evidence from banding studies and population fluctuationsindicates there is some movement of waterbirds among and withinislands (Engilis and Pratt 1993; Reed et al. 1998). More information ofthis kind will allow a better understanding of statewide population sizeand trends.

4.2.6 Determine the sex and age structure of populations.Determine the sex and age structures of important populations (e.g.,waterbird populations that use core wetlands) of all four endangeredwaterbird species.


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4.2.7 Investigate genetic population structure and potential inbreedingdepression. Determine the genetic population structure and the potential forinbreeding depression in all four endangered waterbird species.

4.2.8 Develop population viability analyses for the Hawaiian duck, coot,and moorhen.A population viability analysis has been completed for the Hawaiianstilt (Reed et al. 1994), and similar population viability analyses shouldbe conducted for the Hawaiian duck, coot, and moorhen to help identifythe population numbers and time spans that may serve as usefulpredictors of long term recovery. This exercise will also help identifythose parameters that have the most impact on population viabilitythrough a sensitivity analysis.

4.3 Research Hawaiian waterbird habitat needs and habitat manipulation.Determine the habitat requirements of each species for foraging, nesting, andloafing and develop management techniques to produce these habitatconditions. In particular, research is needed on the use of montane streamsystems by the Hawaiian duck, especially the use of these streams as nestingsites. It is thought that many Hawaiian ducks nest on the banks of uplandstreams near pools of water. Surveys of montane stream habitat should beconducted on Kauaì and Hawaiì to obtain a more accurate populationestimate of the Hawaiian duck. In the past, selected samples of streams inupland habitat were surveyed and the results used to calculate an index of thenumber of Hawaiian ducks per linear mile of stream. This method, as well asother methods, should be evaluated to determine the best way to accuratelyestimate Hawaiian duck populations in montane stream habitats.

5. Plan and implement a public information and awareness program to increasepublic understanding and support for waterbird recovery.The waterbird recovery program cannot be fully successful without a well informedand supportive public. Efforts need to be made to inform the public, increase publicaccessibility to waterbird areas, and provide information on the various programsoutlined in this recovery plan.

5.1 Prepare and distribute television and radio spots, written information,slide programs, videos, films, posters, and displays.Educational materials on waterbird conservation should be developed toimplement a public awareness and information program to enhance recoveryof endangered waterbirds.


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5.2 Coordinate with the Hawaiì Department of Education and privateschools to incorporate wetland and waterbird information into schoolcurricula.Efforts to teach wetland ecology and avian biology should be made within thepublic and private school systems. Wetland refuges and sanctuaries provideexcellent opportunities for field trips and field studies.

5.3 Develop and maintain interpretive displays of endangered waterbirds andwetlands.Interpretive displays should be developed and maintained at wetland habitatareas and at various community locations.

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Table 10. Specific recovery actions recommended for core wetlands in the main Hawaiian Islands.

CORE WETLANDSSTATUS RECOMMENDED RECOVERY ACTIONS

Hectares(Acres)

Responsibility1 Protected2 1.3 1.3.1 1.3.2 1.3.3 1.3.5 1.3.6 1.3.7 1.4 2

Niìhau

Playa Lakes 769 (1900) Private No X X X X

Kauaì

Hanalei National Wildlife Refuge

371 (917) USFWS Yes X X X X X X X X X

Hul‘ìa National Wildlife Refuge


Kawaièle Waterbird Sanctuary

14 (35) HDLNR Yes X X X X X X X

Lumahaì Wetlands 51 (125) Private No X X X X X

Oàhu

James Campbell National Wildlife Refuge


Kawainui Marsh 304 (750) HDLNR Yes X X X X X X X X

Nuùpia Ponds 196 (483) MCBH Yes X X X X X X

Pearl Harbor National Wildlife Refuge

25 (61) USFWS Yes X X X X X X X X

Pouhala Marsh Waterbird Sanctuary

28 (70) HDLNR Yes X X X X X X X

1 Responsibility: HDLNR = Hawaiì Department of Land and Natural Resources, DU = Ducks Unlimited, MCBH = Marine Corps Base Hawaiì, NPS = National Park Service,

USFWS = U.S. Fish and Wildlife Service, USN = U.S. Navy. , NWR = National Wildlife Refuge, Pvt = Private landowner.2 Protected refers to wetland habitats that are secure from development.

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Table 10 (continued). Specific recovery actions recommended for core wetlands in the main Hawaiian Islands.

CORE WETLANDSSTATUS RECOMMENDED RECOVERY ACTIONS

Hectares(Acres)


Molokaì

Kakahaià National Wildlife Refuge

18 (45) USFWS Yes X X X X X X X X

Maui

Kanah~ Pond Wildlife Sanctuary

59 (145) HDLNR Yes X X X X X X X X X

Ke~lia Pond National Wildlife Refuge


Hawaiì

Àimakap~/Kaloko Pond 22 (55) NPS Yes X X X X X X

Loko Waka Ponds 10 (24.5) Pvt/State No X X X X X X X X

Waiakea Pond 16 (39.5) State/County Yes X X X X X X X X X1 Responsibility: HDLNR = Hawaiì Department of Land and Natural Resources, DU = Ducks Unlimited, MCBH = Marine Corps Base Hawaiì, NPS = National Park Service,

USFWS = U.S. Fish and Wildlife Service, USN = U.S. Navy. , NWR = National Wildlife Refuge, Pvt = Private landowner.2 Protected refers to wetland habitats that are secure from development.

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Table 11. Specific recovery actions recommended for supporting wetlands in the main Hawaiian Islands.

SUPPORTING WETLANDS

STATUS RECOMMENDED RECOVERY ACTIONS

Hectares(Acres)


Kauaì

Hanalei Taro Fields and River (that are not part of Hanalei National Wildlife Refuge)

40.4 (100) Pvt/State No X X X X X X

Hanap‘p‘ Salt Ponds 20 (49.4) Pvt/HDLNR No X X X X X X X X

M~n~ Wetlands 81 (200) Pvt/State No X X X X X

Opaekaà Marsh 20 (50) Pvt/HDLNR No X X X X X X X X

Smith’s Tropical Paradise 1.9 (4.7) Pvt/State No X X X X X X X X

Wailua River Bottoms 20 (8) Pvt/State No X X X X X

Waimea River System 64 (158) Pvt/State No X X X X X

Wainiha Valley Taro Fields and River

44 (109) Pvt/County No X X X X X X X

Wait~ Reservoir 151 (373) Private No X X X X X X

1 Responsibility: HDLNR = Hawaiì Department of Land and Natural Resources, DU = Ducks Unlimited, MCBH = Marine Corps Base Hawaiì, NPS = National Park Service,

USFWS = U.S. Fish and Wildlife Service, USN = U.S. Navy. , NWR = National Wildlife Refuge, Pvt = Private landowner. 2 Protected refers to wetland habitats that are secure from development.

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Table 11 (continued). Specific recovery actions recommended for supporting wetlands in the main Hawaiian Islands.

SUPPORTING WETLANDS


Hectares(Acres)


Oàhu

Kaèlepulu Pond 2.2 (5.6) Private No X X X X X X X

Kahuku aquaculture farms 41 (100) Private No X X X X X

Kuilima (Turtle Bay) Sewage Treatment Plant

5 (12.4) Private No X X X X X

Halei`wa Lotus Fields 4.2 (10.6) Pvt/County No X X X X X

H~m~kua Marsh WBS 9 (23) HDLNR/DU Yes X X X X X X X X X

Heèia Marsh 162 (400) DLNR Yes X X X X X X X X

L~ìe Wetlands 81 (200) Private No X X

Niuliì Ponds, Lualualei 16 (40) USN/USFWS Yes X X X X X X X X X

PaikÇ Lagoon WS 13 (33) DLNR Yes X X X X X X X X X

Punahoòlapa Marsh 41 (100) Private No X X X X X X X X X

Ùkoà Marsh 122 (300) Private No X X X X

Waialua Lotus Fields 30 (75) Private No X X X X X X X

Waiheè Marsh 10 (25) Private No X X X X X X X1 Responsibility: HDLNR = Hawaiì Department of Land and Natural Resources, DU = Ducks Unlimited, MCBH = Marine Corps Base Hawaiì, NPS = National Park Service,


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SUPPORTING WETLANDS


Hectares(Acres)


Molokaì

Kaunakakai Sewage Treatment Plant

1.5 (3.7) Maui County No X X X X X X

Kualapuù Reservoir 30 (74) State No X X X X X X

`Æhiàpilo Wetland 10 (25) Maui County Yes

Paialoa Fish Pond 2 (5) Private No X X X X X X

Lanaì

L~naì Sewage Treatment Plant

3 (7.4) County No X X X X X X

Maui

Keànae Point 1.5 (3.7) State No X X X X X X X X

Waiheè Preserve 101(250) Private Yes X X X X X X X X

Hawaiì

Keànae Pond (Keaàu) 2.9 (7.2) Private No X X X X X X X X

Kohala Stock Ponds * Private No X X X X X X

Kona Sewage Treatment Plant

12 (30) County No X X X X X X

1 Responsibility: HDLNR = Hawaiì Department of Land and Natural Resources, DU = Ducks Unlimited, MCBH = Marine Corps Base Hawaiì, NPS = National Park Service, USFWS

= U.S. Fish and Wildlife Service, USN = U.S. Navy. , NWR = National Wildlife Refuge, Pvt = Private landowner. 2 Protected refers to wetland habitats that are secure from development.

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SUPPORTING WETLANDS


Hectares(Acres)


Hawaiì (continued)

Mauna Kea Stock Ponds * Private No X X X X X X

`Æpaeùla Ponds 3 (7.5) Private No X X X X X X

Parker Ranch Ponds 18 (45) Private Yes X X X X X X

Waimanu Valley * County Yes X X X X X X X X X

Waipiò Valley * County No X X X X X X X X X1 Responsibility: HDLNR = Hawaiì Department of Land and Natural Resources, DU = Ducks Unlimited, MCBH = Marine Corps Base Hawaiì, NPS = National Park Service,


* = unknown.


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III. Implementation Schedule

The Implementation Scheduleoutlines actions and estimated costs forthe Hawaiian waterbirds recoveryactions, as set forth in this recovery plan. It is a guide for meeting the recoverygoals outlined in this plan. TheImplementation Schedule includes thefollowing elements:

A. ACTION PRIORITIES

The actions identified in theImplementation Schedule are those that,in our opinion, are necessary to bringabout the recovery of these species. However, the actions are subject tomodification as dictated by new findings,changes in species status, and thecompletion of reocvery actions. Thepriority for each action is given in thefirst column of the ImplementationSchedule, and is assigned as follows:

Priority 1 — An action that must betaken to prevent extinction orprevent the species from decliningirreversibly in the foreseeablefuture.

Priority 2 — An action that must betaken to prevent a significantdecline in species population orhabitat quality, or some othersignificant negative impact short ofextinction.

Priority 3 — All other actions necessary to meet the recovery objectives.

B. ACTION NUMBER ANDDESCRIPTION

The action number and actiondescription are extracted from thestepdown narrative of recovery actionsfound in part II-E of this plan. Pleaserefer back to this narrative for a moredetailed description of each action.

C. LISTING/DELISTING FACTORS

As discussed earlier, we evaluatefive major factors when considering tolist, delist, or reclassify a species:

A —The present or threateneddestruction, modification orcurtailment of its habitat or range;

B — Overutilization for commercial,recreational, scientific, oreducational purposes;

C — Disease or predation;D —Inadequacy of existing regulatory

mechanisms; andE — Other natural or man-made factors

affecting its continued existence.

The Listing Factor column in theImplementation Schedule indicateswhich of the five factors the recoveryaction addresses in order to meet therecovery goals for the endangeredwaterbirds. The majority of recoveryactions in the Implementation Scheduleaddress threats to habitat (factor A),disease and predation (factor C), andother factors such as small populationsizes and reduced distribution (factor E).


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D. RESPONSIBLE PARTIES

In this table, we have identifiedagencies and other parties that webelieve are primary stakeholders in therecovery process for the Hawaiianwaterbirds. Stakeholders are thoseagencies who may voluntarily participatein any aspect of implementation ofparticular actions listed within thisrecovery plan. Stakeholders maywillingly participate in project planning,funding, provide technical assistance,staff time, or any other means ofimplementation. The list of potentialstakeholders is not limited to the listbelow; other stakeholders are invited toparticipate. In some cases, the mostlogical lead agency (based on authorities,mandates, and capabilities) has beenidentified with an asterisk (*).

The listing of an agency in theImplementation Schedule does notrequire, nor imply a requirement or anagreement, that the identified agencyimplement that action(s) or securefunding for implementing action(s). However, agencies willing to participatemay benefit by being able to show intheir own budgets that their fundingrequest is for a recovery action identifiedin an approved recovery plan and istherefore considered a necessary actionfor the overall coordinated effort torecover these four species. Also, section7(a)(1) of the Endangered Species Act(Act) directs all Federal agencies toutilize their authorities in furtherance ofthe purposes of the Act by carrying outprograms for the conservation ofthreatened and endangered species.

We, the U.S. Fish and WildlifeService, have the statutory responsibilityfor implementing this recovery plan. Only Federal agencies are mandated totake part in the effort. Recovery actionsidentified in this plan imply no legalobligations of the State and localgovernment agencies or privatelandowners. However, the recovery ofthe Hawaiian coot, duck, moorhen, andstilt will require the involvement andcooperation of Federal, State, local, andprivate interests.

E. ACTION DURATION

The action duration columnindicates the number of years estimatedto complete the action if it is a discreteaction, or whether it is a continual orongoing action. Occasionally it is notpossible to provide a reasonableestimate of either the time or cost tocomplete an action; these cases aredenoted as To Be Determined (TBD). Continual and ongoing actions aredefined as follows:

Continual (C) -— An action that will be implemented on a routine basisonce begun.

Ongoing (O) -— An action that iscurrently being implemented andwill continue until the action is nolonger necessary.


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F. COST ESTIMATES

The Implementation Scheduleprovides the estimated costs ofimplementing recovery actions for thefirst 5 years after the release of therecovery plan, the years 2005 through2009. Estimates for recovery actions arebased on average costs of similar actionsimplemented to date. For wetlandmanagement, these costs may varyconsiderably depending upon thecondition of the wetland vegetation,hydrology, types of management actions,and actions already occurring in the area.

Annual cost estimates are asfollows:

2005 = $2,442,0002006 = $2,724,0002007 = $2,507,0002008 = $2,098,0002009 = $1,598,000

The total cost to implement thisplan for years 2005 through 2009 is$11,369,000. The total cost toimplement this plan through the year2015, the estimated recovery date, is$18,059,000.

G. ACRONYMS USED IN THE IMPLEMENTATION SCHEDULE

BRD U.S. Geological Survey, Biological Resources DivisionDOCARE Hawaiì Department of Land and Natural Resources,

Division of Conservation and Resources EnforcementDU Ducks UnlimitedFWS -ES U.S. Fish and Wildlife Service, Ecological Services, Honolulu, HawaiìFWS -LE U.S. Fish and Wildlife Service, Law Enforcement, Honolulu, HawaiìFWS -R U.S. Fish and Wildlife Service, Refuges, Honolulu, HawaiìHDLNR Hawaiì Department of Land and Natural Resources, Division of

Forestry and WildlifeHDOA Hawaiì Department of AgricultureHDOE Hawaiì Department of EducationUSDA U.S. Department of AgricultureUSMC U.S. Marine CorpsUSN U.S. NavyWS U.S. Department of Agriculture, Wildlife Services

Second D

raft Revised R

ecovery Plan for H

awaiian W

aterbirds, 2nd R


102

Implementation Schedule for the Second Draft Revised Recovery Plan for Hawaiian Waterbirds, 2nd Revision

Priority

Number

Action

Number

Listing

Factor

Action

Description

Action

Duration

(Years)

Responsible

Party1

Cost Estimates ($1,000's)

FY

2005

FY

2006

FY

2007

FY

2008

FY

2009

Recovery

Total

1 1 A Protect (secure from development)

core (100%) and supporting (at

least 25% for downlisting and 75%

for delisting) wetlands.

3 FWS-R 50 50 50 150

HDLNR 50 50 50 150

1 1.1 A Develop management plans for

core and supporting wetlands.

2 FWS-R 50 50 100

HDLNR 50 50 100

USMC 10 10 20

USN 5 5 10

1 1.2 A,E Coordinate management of core

and supporting wetlands with other

agencies and organizations.

C FWS-ES 5 5 5 5 5 50

HDLNR 5 5 5 5 5 50

1 1.3.1 A, C, E Secure water sources and manage

water levels to maximize nesting

success, brood survival, food

availability, and recruitment of

waterbirds.

C FWS-R 25 25 25 25 25 250

FWS-ES 5 5 5 5 5 50

HDLNR 25 25 25 25 25 250

Second D

raft Revised R

ecovery Plan for H

awaiian W

aterbirds, 2nd R

evision • April 2005

103

Implementation Schedule for the Second Draft Revised Recovery Plan for Hawaiian Waterbirds, 2nd Rev. (cont.)

Priority

Number

Action

Number

Listing

Factor

Action

Description

Action

Duration

(Years)

Responsible

Party1


FY

2005

FY

2006

FY

2007

FY

2008

FY

2009

Recovery

Total

1 1.3.2.1 A Encourage desirable plant species. C FWS-R 50 50 50 50 50 500

HDLNR 50 50 50 50 50 500

USMC 10 10 10 10 10 100

USN 5 5 5 5 5 50

1 1.3.2.2 A Control undesirable plant species. C. HDLNR 150 150 150 150 150 1,500

FWS-R 150 150 150 150 150 1,500

USMC 10 10 10 10 10 100

USN 5 5 5 5 5 50

1 1.3.2.3 A Prevent introduction of invasive

non-native plants.

C FWS-R 5 5 5 5 5 50

HDLNR 5 5 5 5 5 50

USMC 1 1 1 1 1 10

USN 1 1 1 1 1 10

1 1.3.3.1 C Prevent predator access. C FWS-R 80 80 80 80 80 800

HDLNR 80 80 80 80 80 800

USMC 5 5 5 5 5 50

USN 5 5 5 5 5 50

Second D

raft Revised R

ecovery Plan for H

awaiian W

aterbirds, 2nd R



Priority

Number

Action

Number

Listing

Factor

Action

Description

Action

Duration

(Years)

Responsible

Party1


FY

2005

FY

2006

FY

2007

FY

2008

FY

2009

Recovery

Total

104

1 1.3.3.2 C Control mongooses. C FWS-R 80 80 80 80 80 800

HDLNR 80 80 80 80 80 800

USMC 10 10 10 10 10 100

USN 2 2 2 2 2 20

1 1.3.3.3

C Control feral cats. C FWS-R 40 40 40 40 40 400

HDLNR 40 40 40 40 40 400

USMC 10 10 10 10 10 100

USN 2 2 2 2 2 20

1 1.3.3.4 C Control feral dogs. C FWS-R 10 10 10 10 10 100

HDLNR 10 10 10 10 10 100

USMC 2 2 2 2 2 20

USN 2 2 2 2 2 20

1 1.3.3.5 C Control rats. C FWS-R 30 30 30 30 30 300

HDLNR 30 30 30 30 30 300

USMC 5 5 5 5 5 50

USN 2 2 2 2 2 20

Second D

raft Revised R

ecovery Plan for H

awaiian W

aterbirds, 2nd R



Priority

Number

Action

Number

Listing

Factor

Action

Description

Action

Duration

(Years)

Responsible

Party1


FY

2005

FY

2006

FY

2007

FY

2008

FY

2009

Recovery

Total

105

2 1.3.3.6 C Control cattle egrets. C FWS-R 10 10 10 10 10 100

HDLNR 10 20 10 10 10 100

USMC 2 2 2 2 2 20

USN 1 1 1 1 1 10

2 1.3.3.7

C Control tilapia. C FWS-R 30 30 30 30 30 300

HDLNR 30 30 30 30 30 300

USMC 5 5 5 5 5 50

USN 2 2 2 2 2 20

1 1.3.3.8 C Control bullfrogs. C FWS-R 10 10 10 10 10 100

HDLNR 10 10 10 10 10 100

USMC 2 2 2 2 2 20

USN 1 1 1 1 1 10

1 1.3.4 C Prevent introduction of new non-

native predators such as the brown

treesnake (Boiga irregularis).

C FWS-ES 10 10 10 10 10 100

HDLNR 10 10 10 10 10 100

HDOA 10 10 10 10 10 100

Second D

raft Revised R

ecovery Plan for H

awaiian W

aterbirds, 2nd R



Priority

Number

Action

Number

Listing

Factor

Action

Description

Action

Duration

(Years)

Responsible

Party1


FY

2005

FY

2006

FY

2007

FY

2008

FY

2009

Recovery

Total

106

2 1.3.5.1 E Assess and if necessary prevent

intentional or accidental shooting

of waterbirds.

C FWS-R 5 5 5 5 5 50

FWS-LE 5 5 5 5 5 50

*DOCARE 10 10 10 10 10 100

2 1.3.5.2 E Control human access to waterbird

habitats during breeding seasons.

C FWS-R 5 5 5 5 5 50

HDLNR 5 5 5 5 5 50

2 1.3.5.3 A, E Resolve conflicts resulting from

actual or preceived depredation by

waterbirds on aquaculture and

agriculture products by waterbirds.

C FWS-ES 2 2 2 2 2 20

FWS-R 3 3 3 3 3 30

HDLNR 5 5 5 5 5 50

2 1.3.5.4 A Minimize influence of urban

encroachment.

C FWS-ES 5 5 5 5 5 50

FWS-R 5 5 5 5 5 50

HDLNR 5 5 5 5 5 50

USMC 1 1 1 1 1 10

USN 1 1 1 1 1 10

2 1.3.6.1 C Monitor waterbird populations to

detect disease outbreaks as soon as

possible.

C FWS-R 2 2 2 2 2 20

HDLNR 2 2 2 2 2 20

USMC 1 1 1 1 1 10

USN 1 1 1 1 1 10

Second D

raft Revised R

ecovery Plan for H

awaiian W

aterbirds, 2nd R



Priority

Number

Action

Number

Listing

Factor

Action

Description

Action

Duration

(Years)

Responsible

Party1


FY

2005

FY

2006

FY

2007

FY

2008

FY

2009

Recovery

Total

107

2 1.3.6.2 C Take immediate action to restrict

the spread of the disease

outbreaks.

C FWS-R TBD TBD TBD TBD TBD TBD

HDLNR TBD TBD TBD TBD TBD TBD

USMC TBD TBD TBD TBD TBD TBD

USN TBD TBD TBD TBD TBD TBD

2 1.3.7.1 A ,C Monitor water quality. O HDLNR 5 5 5 5 5 50

FWS-R 5 5 5 5 5 50

USMC 1 1 1 1 1 10

USN 1 1 1 1 1 10

2 1.3.7.2 A Restrict introduction of

contaminants to wetland systems.

O HDLNR 2 2 2 2 2 20

FWS-R 1 1 1 1 1 10

USMC 1 1 1 1 1 10

USN 1 1 1 1 1 10

3 1.3.7.3 A Assess nutrient levels and other

parameters that influence core and

supporting wetlands productivity

for waterbirds.

3 HDLNR 2 2 2 6

FWS-R 2 2 2 6

USMC 1 1 1 3

Second D

raft Revised R

ecovery Plan for H

awaiian W

aterbirds, 2nd R



Priority

Number

Action

Number

Listing

Factor

Action

Description

Action

Duration

(Years)

Responsible

Party1


FY

2005

FY

2006

FY

2007

FY

2008

FY

2009

Recovery

Total

108

2 1.4.1 E Continue standardized, biannual,

statewide surveys for all

endangered waterbirds.

O *HDLNR 20 20 20 20 20 200

FWS-R 10 10 10 10 10 100

FWS-ES 3 3 3 3 3 30

USMC 1 1 1 1 1 10

USN 1 1 1 1 1 10

2 1.4.2 E Continue regular, standardized

surveys on core and supporting

wetlands.

C HDLNR 5 5 5 5 5 50

FWS-R 5 5 5 5 5 50

USMC 1 1 1 1 1 10

USN 1 1 1 1 1 10

2 1.4.3 E Develop and improve survey

techniques for the Hawaiian duck

and Hawaiian common moorhen.

2 BRD 50 50 100

2 1.4.4 E Monitor reproductive success on

core wetlands.

C FWS-R 10 10 10 10 10 100

HDLNR 10 10 10 10 10 100

USMC 5 5 5 5 5 50

USN 1 1 1 1 1 10

Second D

raft Revised R

ecovery Plan for H

awaiian W

aterbirds, 2nd R



Priority

Number

Action

Number

Listing

Factor

Action

Description

Action

Duration

(Years)

Responsible

Party1


FY

2005

FY

2006

FY

2007

FY

2008

FY

2009

Recovery

Total

109

2 1.4.5 E Monitor aquatic invertebrate prey

species used by waterbirds and fish

to determine whether they compete

with waterbirds for aquatic

invertebrates.

3 *BRD 10 10 10 30

FWS-R 5 5 5 15

USMC 1 1 1 3

HDLNR 5 5 5 15

1 2.1

E Conduct public information and

awareness program regarding

mallard-Hawaiian duck

interbreeding problem and the

need for the removal program.

3 FWS-ES 5 5 5 15

FWS-R 3 3 3 9

HDLNR 5 5 5 15

1 2.2 E Develop methods for

differentiating between Hawaiian

ducks and mallard-Hawaiian duck

hybrids.

2 FWS-ES, 15 15 30

FWS-R, 15 15 30

BRD 20 20 40

1 2.3

E Implement statewide program to

humanely remove feral mallards

and mallard-Hawaiian duck

hybrids.

3 FWS-R 50 50 50 150

FWS-ES 10 10 10 30

HDLNR 50 50 50 150

WS 50 50 50 150

Second D

raft Revised R

ecovery Plan for H

awaiian W

aterbirds, 2nd R



Priority

Number

Action

Number

Listing

Factor

Action

Description

Action

Duration

(Years)

Responsible

Party1


FY

2005

FY

2006

FY

2007

FY

2008

FY

2009

Recovery

Total

110

1 2.4 E Ensure new stocks of mallards and

closely related ducks are not

brought into the State.

C *HDOA 5 5 5 5 5 50

FWS-LE 5 5 5 5 5 50

2 2.5.1 E Identify sites for reintroduction of

the Hawaiian duck on Maui and

Moloka4 i.

1 HDLNR 4 4

FWS-R 2 2

FWS-ES 2 2

BRD 4 4

2 2.5.2 E Investigate captive propagation

versus translocation for

establishing additional Hawaiian

duck populations and develop a

reintroduction plan.

1 FWS-ES 5 5

HDLNR 5 5

2 2.5.3 E Reintroduce either captive-bred or

translocated Hawaiian ducks to a

protected and managed site on

Maui.

2 HDLNR 30 30 60

BRD 30 30 60

FWS-ES 30 30 60

FWS-R 30 30 60

Second D

raft Revised R

ecovery Plan for H

awaiian W

aterbirds, 2nd R



Priority

Number

Action

Number

Listing

Factor

Action

Description

Action

Duration

(Years)

Responsible

Party1


FY

2005

FY

2006

FY

2007

FY

2008

FY

2009

Recovery

Total

111

3 3.1 E

Conduct thorough surveys of

wetland areas on Maui, Molokaì,

and Hawaiì to confirm that a

Hawaiian common moorhen

population does not already exist.

1 HDLNR 10

10

BRD 10 10

1 3.2 A,E If a population of moorhen is

found on Maui, Molokaì, and

Hawaiì, protect and manage its

wetland habitat.

C HDLNR TBD TBD TBD TBD TBD

FWS-ES TBD TBD TBD TBD TBD

BRD TBD TBD TBD TBD TBD

3 3..3 A,E If no population of moorhen is

found on Maui, Molokaì, or

Hawaiì, habitat quality at

potential reintroduction sites

should be evaluated. A site

meeting certain minimum criteria

should be selected.

1 HDLNR 4 4

FWS-ES 2 2

FWS-R 2 2

BRD 2 2

DU 2 2

Second D

raft Revised R

ecovery Plan for H

awaiian W

aterbirds, 2nd R



Priority

Number

Action

Number

Listing

Factor

Action

Description

Action

Duration

(Years)

Responsible

Party1


FY

2005

FY

2006

FY

2007

FY

2008

FY

2009

Recovery

Total

2 3.4 E Investigate the pros and cons of

captive propagation versus

translocation as a reintroduction

technique.

2 FWS-R 2 2 4

HDLNR 2 2 4

BRD 2 2 4

DU 2 2 4

2 3.5 A,E Reintroduce Hawaiian common

moorhens to a protected and

managed site on Maui, Molokaì,

or Hawaiì and monitor their

survival, dispersal, and any

reproduction.

2 FWS-ES 30 30 60

FWS-R 30 30 60

HDLNR 30 30 60

BRD 30 30 60

1 4.1.1 C Investigate the effects of different

predators on endangered

waterbirds.

4 FWS-R 20 20 20 20 80

HDLNR 20 20 20 20 80

BRD 20 20 20 20 80

1 4.1.2 C Research improved predator

control methods.

3 FWS-R 40 40 40 120

HDLNR 40 40 40 120

*BRD 40 40 40 120

WS 40 40 40 120

Second D

raft Revised R

ecovery Plan for H

awaiian W

aterbirds, 2nd R



Priority

Number

Action

Number

Listing

Factor

Action

Description

Action

Duration

(Years)

Responsible

Party1


FY

2005

FY

2006

FY

2007

FY

2008

FY

2009

Recovery

Total

113

3 4.1.3 C Research improved methods for

non-native plant control and

restore native plants.

3 FWS-R 40 40 40 120

HDLNR 40 40 40 120

*BRD 40 40 40 120

2 4.2.1 E Analyze existing survey data and

investigate current population size,

effective population size, and

population trends.

3 *BRD 30 30 30 90

HDLNR 20 20 20 60

FWS-ES 20 20 20 60

3 4.2.2 E Determine carrying capacity of

wetland habitats.

3 *BRD 5 5 5 15

FWS-ES 5 5 5 15

HDLNR 5 5 5 15

FWS-R 5 5 5 15

3 4.2.3 E Estimate reproductive parameters. 3 BRD 5 5 5 15

FWS-ES 5 5 5 15

HDLNR 5 5 5 15

FWS-R 5 5 5 15

Second D

raft Revised R

ecovery Plan for H

awaiian W

aterbirds, 2nd R



Priority

Number

Action

Number

Listing

Factor

Action

Description

Action

Duration

(Years)

Responsible

Party1


FY

2005

FY

2006

FY

2007

FY

2008

FY

2009

Recovery

Total

114

3 4.2.4 E Estimate mortality rates. 3 BRD 5 5 5 15

FWS-ES 5 5 5 15

HDLNR 5 5 5 15

FWS-R 5 5 5 15

3 4.2.5 E Conduct research on movement of

adults and natal dispersal.

4 BRD 20 20 20 20 80

HDLNR 20 20 20 20 80

FWS-R 20 20 20 20 80

FWS-ES 20 20 20 20 80

3 4.2.6 E Determine the sex and age

structure of populations.

3 BRD 5 5 5 15

FWS-ES 5 5 5 15

HDLNR 5 5 5 15

FWS-R 5 5 5 15

3 4.2.7 E Investigate genetic population

structure and potential inbreeding

depression.

4 *BRD 20 20 20 20 80

FWS-ES 20 20 20 20 80

HDLNR 20 20 20 20 80

FWS-R 20 20 20 20 80

Second D

raft Revised R

ecovery Plan for H

awaiian W

aterbirds, 2nd R



Priority

Number

Action

Number

Listing

Factor

Action

Description

Action

Duration

(Years)

Responsible

Party1


FY

2005

FY

2006

FY

2007

FY

2008

FY

2009

Recovery

Total

115

3 4.2.8 E Conduct population viability

analyses for Hawaiian duck, coot,

and common moorhen.

2 BRD 10 10 20

FWS-ES 10 10 20

3 4.3 E Conduct research on habitat needs

and habitat manipulation.

4 BRD 20 20 20 20 80

FWS-ES 20 20 20 20 80

HDLNR 20 20 20 20 80

FWS-R 20 20 20 20 80

3 5.1 E Prepare and distribute educational

materials.

2 FWS-ES 10 10 20

HDLNR 10 10 20

FWS-R 10 10 20

Second D

raft Revised R

ecovery Plan for H

awaiian W

aterbirds, 2nd R



Priority

Number

Action

Number

Listing

Factor

Action

Description

Action

Duration

(Years)

Responsible

Party1


FY

2005

FY

2006

FY

2007

FY

2008

FY

2009

Recovery

Total

116

3 5.2 E Coordinate with the Hawaiì

Department of Education and

private schools to incorporate

waterbird information into school

curricula.

2 HDLNR 20 20 40

FWS-ES 20 20 40

HDOE 20 20 40

3 5.3 E Develop and maintain interpretive

displays of endangered waterbirds

and wetlands.

2 HDLNR 20 20 40

FWS-ES 10 10 20

FWS-R 20 20 40

TOTALS 2 $2,442 $2,724 $2,507 $2,098 $1,598 $18,059

1An asterisk (*) denotes the lead agency. If no asterisk is present, the agencies share the lead equally. Refer to page 101 for a description of acronyms.2 Some of the above costs are yet to be determined and there are likely to be additional costs as well.


117

IV. References

A. LITERATURE CITED

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American Ornithologists' Union. 1989. Thirty-seventh supplement to the AmericanOrnithologists' Union Checklist of North American Birds. Auk 106:532-538.

American Ornithologists' Union. 1993. Thirty-ninth supplement of the AmericanOrnithologists' Union Checklist of North American Birds. Auk 110:675-682.

American Ornithologists' Union. 1998. Checklist of North American Birds. 7th edition.American Ornithologists’ Union, Washington, D.C.

Atkinson, I.A.E. 1977. A reassessment of factors, particularly Rattus rattus L., thatinfluenced the decline of endemic forest birds in the Hawaiian Islands. PacificScience 31:109-133.

Banko, W.E. 1979. CPSU/UH Avian History Report 2: History of endemic Hawaiianbirds specimens in museum collections. Department of Botany, University ofHawaiì at Manoa, Honolulu, HI. 80 pp.

Bannor, B.K., and E. Kiviat. 2002. Common Moorhen (Gallinula chloropus). In The Birds of North America, No. 685 (A. Poole and F. Gill, eds.). The Birds ofNorth America, Inc., Philadelphia, PA.

Bostwick, J.M. 1982. Habitat loss and hybridization: the dual threat to the koloa. SeniorHonors Thesis, Department of Zoology, University of Hawaiì at Manoa, Honolulu,HI. 80 pp.

Brackney, A.W. and T.A. Bookhout. 1982. Population ecology of common gallinules insouthwestern Lake Erie marshes. Ohio Journal of Science 82: 229-237.

Brown, M. and J.J. Dinsmore. 1986. Implications of marsh size and isolation for marshbird management. Journal of Wildlife Management 50:392-397.

Browne, R.A., C.R. Griffin, P.R. Chang, M. Hubley, and A.E. Martin. 1993. Geneticdivergence among populations of the Hawaiian Duck, Laysan Duck, and Mallard. Auk 110:49-56.


118

Brisbin, I.L., Jr., H.D. Pratt, and T.B. Mowbray. 2002. American Coot (Fulica americana) and Hawaiian Coot (Fulica alai). In the Birds of North America, No.697 (A. Poole and F. Gill, eds.). The Birds of North America, Inc., Philadelphia,PA.

Byrd, G. V. and C.F. Zeillemaker. 1981. Ecology of nesting Hawaiian commongallinules at Hanalei, Hawaiì. Western Birds 12:105-116.

Byrd, G.V., R.A. Coleman, R.J. Shallenberger, and C.S. Arume. 1985. Notes on thebreeding biology of the Hawaiian race of the American coot. ‘Elepaio 45:57-63.

Chang, P.R. 1990. Strategies for managing endangered waterbirds on Hawaiian NationalWildlife Refuges. M.S. Thesis, University Massachusetts, Department of Forestryand Wildlife Management, Amherst, MA. 87 pp.

Coleman, R.A. 1978. Coots prosper at Kakahaià refuge. ‘Elepaio 38:130.

Coleman, R.A. 1981. The reproductive biology of the Hawaiian subspecies of the black-necked stilt, Himantopus mexicanus knudseni. Ph.D. dissertation, PennsylvaniaState University, PA. 106 pp.

Cuddihy, L.W., and C.P. Stone. 1990. Alteration of native Hawaiian vegetation: effectsof humans, their activities and introductions. University of Hawaiì Press,Honolulu, HI. 138 pp.

Dahl, T.E. 1990. Wetland losses in the United States 1780s to 1980s. U.S. Deptartmentof Interior, U.S. Fish and Wildlife Service, Washington, D.C. 13 pp.

Drigot, D.C., Wilcox, B.A., and K.N. Duin. 2001. Marine Corps Base HawaiìIntegrated Natural Resources Management Plan/Environmental Assessment (MCBHINRMP/EA) (2002-2006). Prepared for Marine Corps Base Hawaiì under contractto Geo InSight International, Inc., Carpenteria, CA.

Ducks Unlimited. 1993 to 1997. Survey data for Hawaiian waterbirds. Unpublisheddata on file at Ducks Unlimited, Sacramento, CA.

Ducks Unlimited. 1998. Hawaiian Islands wetlands conservation plan. DucksUnlimited, Inc., Sacramento, CA.

Eijzenga, J. 2003. Identifying key predators of endangered Hawaiian stilt chicks. Abstract presented at the 2003 Wetland Management in the Hawaiian IslandsWorkshop, Honolulu, HI.


119

Engilis, A., Jr. 1988. Surveys and inventories of waterbirds in the State of Hawaiì, aten-year trend analysis. Unpublished Pittman-Robertson Report W-18-R-12, R-III-A.

Engilis, Jr., A., and M. Naughton. 2004. U.S. Pacific Islands Regional ShorebirdConservation Plan. U. S. Shorebird Conservation Plan. U.S. Fish and WildlifeService, Portland, OR. 67 pp.

Engilis, A., Jr. and T.K. Pratt. 1993. Status and population trends of Hawaii’s nativewaterbirds, 1977-1987. Wilson Bulletin 105:142-158.

Engilis, A., Jr., K.J. Uyehara, and J.G. Giffin. 2002. Hawaiian Duck (Anas wyvilliana). In The Birds of North America, No. 694 (A. Poole and F. Gill, eds.). The Birds of North America, Inc., Philadelphia, PA.

Frith, H.J. 1967. Waterfowl in Australia. East West Center Press., Honolulu, HI. 328pp.

Gee, H.K. 2004. Habitat characteristics of taro loì and managed wetlands used by endangered and other waterbird species at Hanalei National Wildlife Refuge.Unpublished report submitted to U.S. Fish and Wildlife, Honolulu, HI.

Giffin, J. 1982. Abundance and distribution of koloa on the Island of Hawaiì. HawaiìDepartment of Land and Natural Resources PR Project No. W-18-R-7. 9 pp.

Griffin, C.R. and R. Browne. 1990. Genetic variation and hybridization in Hawaiianduck and mallards in Hawaiì. Unpublished report. U.S. Fish and Wildlife Service,Hawaiian and Pacific Islands National Wildlife Refuge Complex, Honolulu, HI. 22pp. + tables.

Griffin, C.R., R.J. Shallenberger, and S.I. Fefer. 1989. Hawaii's endangered waterbirds:a resource management challenge. In Freshwater Wetlands and Wildlife. Department of Energy symposium No. 61 (R.R. Schwartz and Gibbons, eds.). U.S.Department of Energy, Oakridge, TN.

Hawaiì Division of Forestry and Wildlife. 1976-2003. Biannual Hawaiian waterbirdsurvey data. Summarized by Hawaiì Natural Heritage Program and Pacific IslandsFish and Wildlife Office, Honolulu, HI.

Hawaiì Division of Forestry and Wildlife. 1978. Description of waterbird habitats asrelated to food availability and feeding behavior of endangered waterbird species onthe islands of Kauai and Oahu. Job progress report; W-18-R-3, Job R-III-D, July 1,977 to June 30, 1978. Hawaiì Division of Forestry and Wildlife, Honolulu, HI.


120

Hodges, C.S. and R.J. Nagata. 2001. Effects of predator control on the survival and breeding success of the endangered Hawaiian Dark-rumped Petrel. Studies in AvianBiology 22:308-318.

Hu, D., C. Glidden, J.S. Lippert, L. Schnell, J.S. Maclvor, and J. Meisler. 2001. Habitat use and limiting factors in a population of Hawaiian Dark-rumped Petrels onMauna Loa, Hawaiì. Studies in Avian Biology 22:234-242.

Kirch, P.V. 1982. The impact of the prehistoric Polynesians on the Hawaiian ecosystem. Pacific Science 36:1-14.

Kirch, P.V. 1983. Man’s role in modifying tropical and subtropical Polynesianecosystems. Archaeology in Oceania 13:26-31.

Mangel, M. and C. Tier. 1994. Four facts every conservation biologist should knowabout persistence. Ecology 75:607-614.

Meffe, G.K. and C.R. Carroll. 1996. Principles of conservation biology. SinauerAssociation Inc., Sunderland, MA. 729 pp.

Morin, M.P. Hawaiian fishponds and endangered waterbirds on the Kona coast. 1994Transactions of the Western Section of the Wildlife Society 30:66-71.

Munro, G.C. 1960. Birds of Hawaiì. Charles E. Tuttle Company, Rutland, VT andTokyo, Japan. 192 pp.

Nagata, S.E. 1983. Status of the Hawaiian Gallinule on lotus farms and a marsh onOàhu, Hawaiì. M.S. thesis, Colorado State University, Fort Collins, CO.

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Olson, S.L. and H.F. James. 1991. Descriptions of thirty-two new species of birds fromthe Hawaiian Islands: Part I. Non-passeriformes. Ornithological Monographs 45:1-88.

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Pratt, H.D. 1987. Occurrence of the North American coot (Fulica americanaamericana) in the Hawaiian Islands, with comments on the taxonomy of theHawaiian coot. ‘Elepaio 47:24-28.

Pratt, H.D., P.L. Bruner, and D.G. Berrett. 1987. A field guide to the Birds of Hawaiìand the Tropical Pacific. Princeton University Press, Princeton, NJ. 409 pp.

Pyle, R.L. 1988. Checklist of the birds of Hawaiì - 1988. ‘Elepaio 48:95-106.

Pyle, R.L. 2002. Check list of bird of Hawaiì - 2002. ‘Elepaio 62:137-148.

Ratner, B. 2000. Environmental contaminants and colonial waterbirds. Issue reportfrom Review Draft II of the North American Waterbird Conservation Plan, VolumeOne: Seabirds and Colonial Waterbirds, 23 October 2001, Waterbird ConservationPlan Steering Committee, Washington, D.C. Available online: http://www.nacwcp.org/plan/rpt-contaminants.pdf.

Rauzon, M.J., J.S.E. Garrison, T.C. Menard, K.N. Duin, and B. Wilcox. 2002. MarineCorps Base Hawaiì Stilt Recovery in the Koòlaupoko District, Oàhu. DraftReport prepared for Environmental Department, Marine Corps Base Hawaiì, K~neòhe, HI.

Reed, J.M. and L. W. Oring. 1993. Long-term population trends of the endangered Aeò(Hawaiian stilt, Himantopus mexicanus knudseni). Transactions of the WesternSection of the Wildlife Society 29:54-60.

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Reed, J.M., M. Silbernagle, A. Engilis, Jr., K. Evans, and L. Oring. 1998. Movements ofHawaiian stilts (Himanotopus mexicanus knudseni) as revealed by bandingevidence. Auk 115:791-797.


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Ribic, C., S. Lewis, S. Melvin, J. Bart, and B. Peterjohn, compilers. 1999. Proceedingsof the marsh bird monitoring workshop, U.S. Fish and Wildife Service, PatuxentResearch Refuge, Laurel, MD.

Robinson, J.A., J.M. Reed, J.P. Skorupa, and L.W. Oring. 1999. Black-necked stilt(Himantopus mexicanus). In The Birds of North America, No. 449 (A. Poole and F.Gill, eds.). The Birds of North America, Inc., Philadelphia, PA. 32 pp.

Rothschild, W. 1900. Birds of Laysan. P.H. Porter, London, England

Sargeant, A.B. and D.G. Raveling. 1992. Mortality during the breeding season. Pages396 to 422 in Ecology and management of breeding waterfowl (B.D.J. Batt et al.,eds.). University of Minnesota Press, Minneapolis, MN. 635 pp.

Schwartz, C.W. and E.R. Schwartz. 1949. The game birds in Hawaiì. Division Fishand Game and Board of Commissioners of Agriculture and Forestry, Honolulu, HI. 168 pp.

Scott, J.M., S. Conant, and C. Van Riper, III. 2001. Introduction. In Scott, J.M., S.Conant, and C. Van Riper, III (eds). Evolution, ecology, conservation, andmanagement of Hawaiian birds: a vanishing avifauna. Studies in Avian Biology No.22.

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Smith, D.G., and J.T. Polhemus. 2003. Habitat use and nesting activity by the Hawaiianstilt (Himantopus mexicanus knudseni) and Hawaiian moorhen (Gallinula chloropussandvicensis) at the H~m~kua Marsh State Wildlife Sanctuary, Kailua, Oàhu. Èlepaio 63:59-62.

Stone, C.P. 1989. Hawaii's wetlands, streams, fishponds, and ponds. Pages 125 to 136in Conservation Biology in Hawaiì (C.P. Stone and D.B. Stone, eds.). Universityof Hawaiì Press, Honolulu, HI. 252 pp.

Swedberg, G.E. 1967. The Koloa, a preliminary report on the life history and status ofthe Hawaiian duck (Anas wyvilliana). Federal Aid to Wildlife Restoration Act


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Takano L.L. 2003. Seasonal movements, home range, and abundance of the Marianacommon moorhen (Gallinula chloropus guami) on Guam and the Northern MarianaIslands. M.S. thesis, Oregon State University, Corvallis, OR. 96 pp.

Takano, L.L. and S.M. Haig. 2004a. Distribution and abundance of the Mariana common moorhen. Waterbirds 27: 245-250.

Takano, L.L., and S.M. Haig. 2004b. Seasonal movement and home range of the Mariana Common Moorhen. Condor 106:652-663.

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Tomich, P.Q. 1969. Mammals in Hawaiì. Bernice P. Bishop Museum SpecialPublication 57. Bishop Museum Press, Honolulu, HI. 238 pp.

Udvardy, M.D.F. 1960. Movements and concentrations of the Hawaiian coot on theIsland of Oàhu. ‘Elepaio 21:20-22.

Ueoka, M. 1979. Limited study of nesting stilt on the islands. Hawaiì Department ofLand and Natural Resources, Division of Forestry and Wildlife, Wailuku, Maui,Hawaiì. Unpublished Pittman-Robert Report W-18-R-1/4, R-III-C.

U.S. Fish and Wildlife Service. 1967. Native Fish and Wildlife: Endangered Species. Federal Register 32:4001.

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U.S. Fish and Wildlife Service. 1985. Recovery Plan for the Hawaiian Waterbirds. U.S. Fish and Wildlife Service, Portland, OR. 99 pp.

U.S. Fish and Wildlife Service. 1987. Field Guide to Wildlife Diseases. General fieldprocedures and diseases of migratory birds (M. Friend, ed.) U.S. Fish and WildlifeServices Resource Publication. 167. 225 pp.

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U.S. Fish and Wildlife Service. 1999. Draft Revised Recovery Plan for the Hawaiian Waterbirds Second Revision. U.S. Fish and Wildlife Service, Portland,OR. 107 pp.

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U.S. Fish and Wildlife Service. 2004b. Draft Revised Recovery Plan for the LaysanDuck (Anas laysanensis). U.S. Fish and Wildlife Service, Portland, OR. 94 pp.

U.S. Fish and Wildlife Service. 2004c. Draft Revised Recovery Plan for the N‘n‘(Branta sandvicensis). U.S. Fish and Wildlife Service, Portland, OR. 148 pp.

van Riper, C., III, S.G. van Riper, M.L. Goff, and M. Laird. 1986. The epizootiologyand ecological significance of malaria in Hawaiian land birds. EcologicalMonographs 56: 327-344.

Waddington, J.S. 2003. Cyanotech Corporation Conservation Plan for the Hawaiian Stilt (Himantopus mexicanu knudseni) Annual Report for 2003. KeahÇlePoint, HI.


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Warner, R.E. 1968. The role of introduced diseases in extinction of the endemic Hawaiian avifauna. Condor 70: 101-120.

Weller, M.W. and L.H. Fredrickson. 1973. Avian ecology of a managed glacial marsh. Living Bird 12: 269-291.

Wilson, S.B., and A.H. Evanns. 1890-99. Aves Hawaiiensis: the birds of Sandwich Islands. R.H. Porter, London, England.

Worthington, D.V. 1998. Inter-island dispersal of the Mariana Common Moorhen: arecolonization by an endangered species. Wilson Bulletin 110:414-417.

B. PERSONAL COMMUNICATIONS

Asquith, A., former Refuge Biologist, Hanalei National Wildlife Refuge, Kauaì, HI.

Donaldson, P., Private Citizen, Pearl City, HI.

Duvall, F., Wildlife Biologist, Hawaiì Department of Land and Natural Resources,Division of Forestry and Wildlife, Wailuku, Maui, HI.

Engilis, A., Jr., formerly with Ducks Unlimited, Western Regional Office, Rancho Cordova, CA.

Gibson, L., Fish and Wildlife Biologist, Pacific Islands Fish and Wildlife Office, U.S. Fish and Wildlife Service, Honolulu, HI.

Gundersen, K., Project Coordinator, Kauaì Invasive Species Committee, L§hue, HI.

Kwon, J., Fish and Wildlife Biologist, Pacific Islands Fish and Wildlife Office, U.S. Fish and Wildlife Service, Honolulu, HI.

Leinecke, J., Project Leader, Hawaiian/Pacific Islands National Wildlife RefugeComplex, U.S. Fish and Wildlife Service, Honolulu, HI.

Morin, M., formerly with Hawaiì Birds of North America Project, Kailua-Kona, HI.

Nishimoto, M., Refuge Biologist, U.S. Fish and Wildlife, Maui National Wildlife Refuge Complex, K§hei, HI.


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Silbernagle, M., Wildlife Biologist, Oàhu National Wildlife Refuge, U.S. Fish andWildlife Service, Haleìwa, HI.

Swenson, C., Fish and Wildlife Biologist, Pacific Islands Fish and Wildlife Office, U.S.Fish and Wildlife Service, Honolulu, HI.

Takano, L., Fish and Wildlife Biologist, Pacific Islands Fish and Wildlife Office, U.S.Fish and Wildlife Service, Honolulu, HI.

Telfer, T., former Kauaì District Biologist, Division of Forestry and Wildlife, HawaiìDepartment of Land and Natural Resources, L§hue, HI.

Ueoka, M., Wildlife Biologist, Hawaiì Department of Land and Natural Resources, Division of Forestry and Wildlife, Wailuku, Maui, HI.

Uyehara, K., formerly with Ducks Unlimited, Kailua-Kona, HI.

VanderWerf, E., Hawaiian Bird Recovery Coordinator, U.S. Fish and Wildlife Service,Honolulu, HI.

Viernes, K., Refuge Biologist, U.S. Fish and Wildlife Service, K§lauea Point NationalWildlife Refuge, HI.

Walker, R., former Wildlife Chief, Hawaiì Department of Land and Natural Resources, Division of Forestry and Wildlife, Honolulu, HI.


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V. Appendices

APPENDIX A. Core Wetlands

Core Wetlands: Areas that provide habitat essential for supporting largerpopulations of Hawaiian waterbirds that comprise the bulk of thenumbers prescribed for recovery. These sites must be protectedand managed to recover Hawaiì’s waterbirds.

Niìhau

Playa Lakes - The Playa Lakes on Niìhau are seasonally some of the mostimportant wetlands in the State. Three large lakes dominate the 760-hectare (1,900-acre) wetland complex. Large numbers of Hawaiian coots, stilts, and migratoryducks have been observed on these lakes, but they have not been surveyed since1999. The long-term protection of these wetlands should be sought through acooperative effort with the private landowner.

Kauaì

Hanalei National Wildlife Refuge - The first National Wildlife Refuge establishedfor waterbirds in Hawaiì was acquired in Hanalei Valley, on Kauaì, in 1972. This367-hectare (917-acre) refuge supports large populations of all four endangeredwaterbirds and numerous migratory waterfowl. Taro is grown on portions of therefuge by local farmers, a practice that dates back more than 1,200 years in thevalley. Management of wetland units for waterbird habitat is ongoing and hasrecently focused on providing additional foraging habitat.

Hul‘ìa National Wildlife Refuge - In 1973, Hul‘ìa National Wildlife Refuge wasestablished on Kauaì, south of the town of L§huè. The refuge encompasses 98hectares (241 acres) of river bottom habitat along the Hul‘ìa River. It wasestablished to provide open, productive wetlands for endangered Hawaiianwaterbirds.

Lumahaì Valley - Lumahaì Valley in northern Kauaì covers approximately 121hectares (300 acres) and is utilized by all four endangered waterbird species. Thelower reaches of Lumahaì Valley provide relatively undisturbed high qualityfeeding, loafing, and possibly nesting habitat. The land is owned by Bishop Estate. Protection of this area is needed. A partnership should be pursued to protect andpreserve Lumahaì Valley through a cooperative agreement, funding, or habitat withthe landowner.


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Oàhu

James Campbell National Wildlife Refuge - Established in 1976, this refuge hasbecome one of the State's most important waterbird refuges. The refuge size (66hectares [164 acres]), management, and location all contribute to its importance. The refuge contains a mix of naturally occurring, spring-fed marshes and man-madeponds and impoundments. The land is currently only leased to the Fish and WildlifeService and permanent protection is needed. The permanent wetlands of the site aresupported by numerous seasonal wetlands not currently within refuge boundaries. With additional protection measures, we have an opportunity to protect an importantwetland system that supports waterbirds throughout their annual cycle.

Kawainui Marsh - Historically, this 300-hectare (741-acre) marsh on windwardOàhu contained a 180-hectare (450-acre) fishpond used by native Hawaiians. It isfed primarily by Manauwili and Kahanaiki streams. The marsh feeds into a canaland then into Kailua Bay. Most of the marsh is now vegetated, but some open waterexists near the center. Expansion of open water areas would facilitate use by all fourendangered waterbird species, which now use the area in small numbers. KawainuiMarsh is currently owned by the Department of Land and Natural Resources (76hectares [188 acres] around the marsh periphery) and the City and County ofHonolulu (the remaining 224 hectares [553 acres]). The entire area is managed bythe State of Hawaiì. In 1993, the State began extensive planning efforts for wetlandrestoration, habitat development, and long term management.

Nuùpia Ponds - An interagency agreement exists under the Sikes Act between theU.S. Marine Corps, the Fish and Wildlife Service, the Hawaiì Department of Landand Natural Resources, and the National Marine Fisheries Service for managementof this wetland area. Eight shallow ponds, totaling approximately 196 hectares (483acres), comprise the Nuùpia Pond complex at the K~neòhe Marine Corps BaseHawaiì on the eastern side of Oàhu. The open water and extensive mudflats withstands of Batis maritima (pickleweed ) provide valuable habitat for Hawaiian stilts. The ponds range in salinity from approximately that of the ocean (35 parts perthousand [ppt]) to hypersaline (100 ppt). Freshwater upwelling occurs in someponds creating brackish water conditions (15 to 20 ppt) that support scatteredpatches of robust emergent plants. Over the past 20 years, the number of stilts atthese ponds have doubled from about 60 to over 130 birds, which is currentlyapproximately 10 percent of Oahu’s stilt population (Rauzon et al. 2002). Variousmanagement plans have been developed and implemented for this area, the mostcomprehensive being an Integrated Natural Resources Management Plan for theMarine Corps Base Hawaiì (Drigot et al. 2001).

Pearl Harbor National Wildlife Refuge - This refuge, composed of two man-madewetland units (Honouliuli and Waiawa) totaling 25 hectares (62 acres), is managedunder a cooperative agreement with the U.S. Navy. The refuge was established in


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1976 as mitigation for construction of the Honolulu International Airport ReefRunway. The refuge is managed for a variety of waterbirds and supports substantialnumbers of the four endangered waterbirds and numerous migratory waterfowl andshorebirds.

Molokaì/Maui

Kakahaià National Wildlife Refuge - In 1977, Kakahaià National Wildlife Refugewas established on Molokai's southern shore. The 18-hectare (45-acre) refugeprotects a pond and man-made impoundment. Twelve species of birds, includingthe Hawaiian coot and stilt, use this area.

Kanah~ Pond Sanctuary - In 1952, Kanah~ Pond on Maui was designated as the firstState wetland sanctuary. The sanctuary encompasses a 57-hectare (143-acre)wetland that is owned by the Hawaiì Department of Transportation and managed bythe Hawaiì Department of Land and Natural Resources. It provides valuablenesting, loafing, and feeding habitat for coots and stilts.

Ke~lia Pond National Wildlife Refuge - This important 280-hectare (692-acre)wetland and pond is located near K§hei. Representing some of the last remainingnatural wetland habitat in the State of Hawaiì, the area provides valuable nesting,loafing, and feeding habitat for coots and stilts. The area was acquired in 1992 andestablished as a National Wildlife Refuge. The U.S. Fish and Wildlife Service andDucks Unlimited are currently developing a restoration and management plan thatwill improve habitat for waterbirds, provide secure water delivery to restored ponds,and provide for public use activities (e.g., wildlife viewing and education).

Hawaiì

Àimakap~ /Kaloko Pond - This wetland comprises approximately 10 hectares (25acres) of open water and another 8 hectares (20 acres) of marsh. The surroundingarea is developing commercially. Àimakap~ Pond is an important Kona Coastwetland that supports many Hawaiian coots and stilts. The National Park Serviceacquired these ponds as part of Kaloko-HonokÇhau National Historic Park. TheNational Park Service is currently monitoring bird use on the marsh; however,management plans emphasize restoration of the area as a demonstration fishpond forcultural resource preservation.

Loko Waka Pond - The Loko Waka Ponds are located near Hilo, and the privatelyowned portions are managed for fish culture. They provide nesting and feedinghabitat for coots. The use of pesticides should be closely coordinated with theHawaiì Division of Aquatic Resources to prevent habitat damage. Agreementsshould be sought with the landowner to enhance habitat for waterbirds. The publicareas of these ponds near Hilo are managed for recreational fishing. Technical


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assistance to private land managers could allow enhancement of waterbird habitat,especially for Hawaiian coots. Vegetation and water control management mayincrease the habitat value of Loko Waka Pond.

Wai~kea Pond - Wai~kea Pond, is an estuarine pond that drains into the WailoaRiver, which then flows eastward about 0.5 miles into Hilo Bay. Waiakea Pond isone of the largest freshwater habitats for endangered waterbirds and provides habitatfor a large portion of the island’s Hawaiian coot population. It also harbors apopulation of feral mallards, which should be removed.


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APPENDIX B. Supporting Wetlands

Supporting Wetlands: Additional areas that provide habitat important forsmaller waterbird populations or that provide habitatneeded seasonally by segments of the waterbirdpopulations during part of their life cycle. Protectionand management of these or similar wetlands is requiredto recover Hawaii`s waterbirds, but there is room forsome flexibility in which sites must be managed, and itis possible that other sites may fulfill the same needs asthose listed here.

Kauaì

Hanalei Taro Fields and River - Protection in needed for the additional taro acreagein Hanalei Valley that is not part of the Hanalei National Wildlife Refuge. Thesefarms are utilized by all four endangered waterbirds. Waterbirds move betweenthese farms and refuge taro fields, and between Hanalei Valley sites and otherwetlands on Kauaì and Niìhau. Hawaiian ducks, coots, and moorhens are alsoknown to utilize areas of the Hanalei River. Thus, these areas provide a continum ofhabitat between core wetland areas. Expanded outreach to farmers and education isthe most appropriate management tool for the Hanalei taro fields and predatorcontrol may also be possible.

Hanap‘p‘ Salt Ponds - The Hanap‘p‘ Salt ponds are located on the southern coastof Kauaì. This area is made up of two ponding basins separated by a road. Hawaiian coots, ducks, and especially stilts are known to utilize these ponds. Hawaiian stilts find this site attractive during winter months when rainfall isabundant, and year-round use of these ponds could be encouraged with effectivemanagement. Hanap‘p‘ is mid-way between two stilt nesting and feeding areas(M~n~ and L§huè Settling Basins) and provides a continum of habitat between theseareas.

Kawaièle Waterbird Sanctuary - The State, through a sand mining lease, hascreated several ponds totaling 14 hectares (35 acres). These ponds have beensculpted to provide nesting islands, sloped banks, and water depths suitable for allfour endangered waterbirds.

M~n~ Wetlands - Approximately 81 hectares (200 acres) of ponds, ditches,reservoirs, and flooded pastures remain from what was once a 810-hectare (2,000-acre) wetland expanse. Presently there is considerable use of this area by all fourwaterbird taxa. Habitat restoration is underway through efforts by Ducks Unlimitedand the Pacific Coast Joint Venture, but further habitat restoration and management


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of the area is necessary to realize its full potential for waterbird recovery. Althougha formal cooperative agreement between the State, Kekaha Sugar Company, andHawaiian Homelands declares the M~n~ Plain a wildlife sanctuary, a more formaldesignation of specific waterbird areas should be made. The decline of the sugarindustry in Hawaiì puts future land use in this area in question.

`Æpaekaà Marsh - Adjacent to the Wailua River, `Æpaekaà Marsh is a 20-hectare(50-acre) wetland that supports Hawaiian ducks, moorhens, and coots. The Statealready owns portions of the land. Protection of additional private land, andrestoration and enhancement of managed units, could create an important wetlandrefuge.

Smith’s Tropical Paradise (Paradise Pacific) - The lowest flatland along the WailuaRiver, once a tidal marsh, was modified in the 1960s by construction as a tropicalgardern. This area contains seven shallow ponds, four of which are utilized byendangered waterbirds, especially moorhens. A cooperative agreement with thelandowner should be developed to insure that this habitat is protected for waterbirds,and ideally to develop a restoration and management plan that will improve habitatfor waterbirds. This site is unique in that it could also be an important area foreducation about waterbird conservation for the public (e.g., wildlife viewing). Feralmallards and hybrids have been observed at this site, and should be removed.

Wailua River Bottoms - The Wailua River is located in the District of Kawaihau andruns parallel to `Æpaekaà Stream, which joins the Wailua River at a pointapproximately one-half mile west of the river mouth. Flat pasture lands border thedownstream portion of the Wailua River, although most of the sloping hillsides areheavily forested. Hawaiian ducks, moorhens, and coots are known to utilize theriver bottoms for foraging.

Waimea River System - the Waimea River is located in the southwestern region ofKauaì. It is the island’s largest river system, surrounded by densely vegetated land,and on the lower reaches, by taro patches agricultural lands. The Hawaiian duck isthought to utilize upland portions of the river and lower reaches may be goodforaging habitat for Hawaiian coots and moorhens, although surveys have not beenconducted to quantify waterbird usage because access to agricultural lands arelimited.

Wait~ Reservoir - Wait~ is the largest fresh water reservoir on Kauaì. It issurrounded mostly by cane fields, although emergent grasses line the edge whenwater level is high. Large numbers of Hawaiian coots periodically utilize thisreservoir for loafing and feeding. Hawaiian ducks, moorhens, and stilts have alsobeen recorded at this site. A cooperative agreement with the landowner shouldfocus on measures to insure that feeding and loafing habitat for coots are notdisturbed unnecessarily.


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Wainiha Valley Taro Fields and River - Wainiha Valley is located in northernKauaì and provides a wide variety of wetland habitat for waterbirds, which includesa large estuarine area, flowing freshwater stream, ephemeral flooded pastures andtaro fields. The Hawaiian stilt and moorhen are found in the taro fields and theHawaiian coot is found in the lower stream and estuarine area. The Hawaiian duckmay also utilize the valley. A cooperative agreement with the landowner should bedeveloped that insures maintenance of stream flow throughout its normal course inthe valley, and possibly predator trapping.

Oàhu

Kahuku aquaculture farms - Kahuku area wetlands provide valuable foraging andmarginal nesting habitats for all four endangered waterbird species. Prior to 1994,this area supported one of the largest aquaculture developments (Amorient PrawnFarms) in the State. Much of the area is currently undergoing redevelopment byMing Dynasty Aquaculture. The natural wetlands in the area have becomeovergrown with invasive species such as Batis maritima. Long-term protection isneeded for the aquacultural and wetland ponds in this area.

Kaèlepulu Pond - This privately-owned wetland is surrounded by housingdevelopment but was once more than 200 acres in size (Shallenburger 1977). It isnow approximately 1.2 hectares (3 acres) and supports nesting Hawaiian coots, aswell as smaller numbers of nesting Hawaiian common moorhens and Hawaiianstilts. Vegetation management and predator control are carried out on the wetland.

Kuilima (Turtle Bay) Sewage Treatment Plant - This site is located in northernOàhu and is periodically used by large numbers of Hawaiian coots and stilts. Long-term protection should be encouraged through cooperative agreementsbetween the landowner and natural resource agencies.

Haleìwa Lotus and Taro Fields - The Haleìwa lotus and taro fields are locatedprimarily in the Haleìwa lowlands between Anahulu and Kaukonahua streams. Thetaro and lotus files are fed by springs, wells, and perennial streams, depending ontheir location. This area provides important habitat for waterbirds, particularly theHawaiian moorhen.

H~m~kua Marsh Waterbird Sanctuary - H~m~kua Marsh is a 9-hectare (23-acre)wetland associated with Kawainui Marsh on the windward cost of Oàhu. Locatedalong H~m~kua Drive in Kailua, it is utilized by all four species of waterbirds andhas been secured by Ducks Unlimited, who donated the land to the HawaiìDepartment of Land and Natural Resources. The site has been greatly improved ashabitat for waterbirds, but further improvement might be possible through additionalenhancement.


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Heèia Marsh - This 160-hectare (400-acre) area was formerly a complex of tidalmarshes and open water areas. It has been substantially modified and presentlyconsists of nonnative mangroves, remnants of ponds, and wet pasture grazed bycattle. This wetland area should be restored and managed to provide enhancedhabitat for all four waterbirds. The State secured this property through a landexchange in 1992. The Hawaiì Department of Land and Natural Resources iscurrently planning for enhancement and management of the site’s upland andwetland resources.

L~ìe Wetlands - This 81-hectare (200-acre) wetland complex comprises threenatural ponds and several aquaculture ponds. All are linked hydrologically and allfour endangered waterbird species use the site. This area is owned by the Church ofJesus Christ of Latter-day Saints and long-term protection is planned for the site. Ifrestored and managed, the L~ìe Wetlands would be an important addition to theavailable wetland habitat in the Kahuku area.

Niuliì Ponds Wildlife Refuge - Located at Naval Computer and TelecommunicationArea Master Station Pacific (NCTAMSPAC) Radio Transmitter Facility (RTF)Lualualei on Oàhu's leeward coast, this 35.7-hectare (88.4-acre) refuge wasestablished by the Navy in 1972. The refuge is managed through a cooperativeagreement between the Navy and the U.S. Fish and Wildlife Service. The refugeincludes three small man-made ponds built for disposal and treatment of wastewaterrunoff effluent. Improvements to the ponds (e.g., installation of a solar-poweredgroundwater pump to provide additional freshwater in the primary pond; periodiccontrol of California grass and other invasive nonnative plant species; and control offeral and nonnative animals) facilitated the creation of wetland habitat thatsupported the four endangered waterbirds in addition to other waterfowl andshorebirds. However, recent realignment of Naval facilities has eliminated themajority of source water for the ponds and substantially reduced their size from 3.9hectares (9.6 acres) to approximately 0.4 hectares (1 acre). An Integrated NaturalResources Management Plan for the area notes that Navy Region Hawaii willmaintain the wetland as long as endangered waterbirds continue to populate theponds (Naval Region Hawaii 2001).

Punahoòlapa Marsh - This former pond and large marsh of over 40 hectares (100acres) has been highly altered due to the development of a golf course resort. Thegolf course surrounds the site, and a second planned resort will impact its coastalbuffer. All four endangered waterbird species use this area. It has been suggestedthat incorporating Punahoòlapa Marsh into the refuge system as part of the JamesCampbell National Wildlife Refuge would ensure protection and management ofthis site.

Ùkoà Marsh - This is a 122-hectare (300-acre) freshwater marsh near Haleìwa onthe northern shore of Oàhu. Much of this privately owned marsh has been


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overgrown by nonnative plants, but it still provides valuable waterbird habitat. Acooperative agreement with the landowner should be developed to ensure that thishabitat is protected and managed for waterbirds.

Waialua Lotus Fields - Relatively few taro and lotus fields remain in what was oncea large wetland agriculture development on the northern shore of Oàhu. The lotusfields in Waialua support the State's highest concentration of Hawiian commonmoorhens, which use the area to nest and feed. Hawaiian stilts, numerousshorebirds, and night-herons also feed in the wetland. Long-term protection ofWaialua Lotus Fields could be reached through cooperative agreements betweenlandowners and natural resource agencies.

Waiheè Marsh - This 10-hectare (25-acre) marsh is located along the windwardcoast of Oàhu near the town of Wai~hole and supports limited numbers ofwaterbirds. The site is adjacent to the main road and close to City and County ofHonolulu parks that could be integrated with wetland habitat conservation for publicenvironmental education opportunities. Protection and enhancement of WaiheèMarsh could improve its value to endangered waterbirds.

Molokaì/L~naì/ Maui (Maui Nui)

Kaunakakai Sewage Treatment Plant - This site lies just north of the town ofKaunakakai, Molokaì. Hawaiian stilts and especially Hawaiian coots in largenumbers have been observed to utilize this site. Artificial nesting platforms placedin the ponds have encouraged coot nesting at this site. Long-term protection shouldbe encouraged through cooperative agreements between the County of Maui andnatural resource agencies.

Kualapuù Reservoir - Located in north-central Molokaì, this reservoir periodicallysupports relatively large numbers of coots. Monitoring of bird populations andprotection of Kualapuù Reservoir should be sought.

`Æhiàpilo Wetland - This 10-hectare (25-acre) wetland is managed by the Countyof Maui and is an important area for endangered waterbirds (primarily stilts andcoots) and migratory waterfowl. The wetland is part of the `Æhiàpilo Playa(approximately 25 hectares [60 acres]), a seasonal wetland on the southern coast ofMolokaì near Kaunakakai. The wetland has become overgrown with pickleweedand other introduced plant species. As mitigation for wetland fill, the countyworked with Ducks Unlimited to develop a wetland enhancement and managementplan. The habitat enhancement was completed in November 1999, and providedopen flats for nesting Hawaiian stilts, an additional 4 hectares (10 acres) ofseasonally-flooded mudflat, an additional 1 hectare (3 acres) of semi-permanentponds and channels to extend the hydroperiod (i.e. the period of time when awetland normally receives its water) of Hawaiian coot and stilt chick foraging


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habitat, and predator fencing. The 10-hectare (25-acre) wetland is surrounded by a90-meter (300-foot) fenced buffer zone. Ducks Unlimited biologists are monitoringand conducting predator and vegetation control in conjunction with the county.

Paialoa Fish Pond - This is a privately owned freshwater marsh, about 2 hectares (5acres) in size, used by coots and stilts. A cooperative agreement should be sought with the landowner to prevent habitat alteration.

L~naì Sewage Treatment Plant - This sewage treatment plant is located southwestof L~naì City adjacent to Kaumalapau Highway. It provides habitat for theHawaiian stilt. Up to 100 Hawaiian stilts have been observed using this site. Long-term protection should be encouraged through cooperative agreements between theCounty of Maui and natural resource agencies.

Keànae Point - Waiokamilo and Palauhulu streams drain the upper Keànae Valleyinto an open ephemeral marsh. Below the marshland are extensive taro fields thatare utilized by waterbirds. Long-term protection and management throughcooperative agreements between private landowners and natural resource agenciesshould be encouraged.

Waiheè Coastal Dunes and Wetlands (Waiheè Preserve) - The Waiheè Preserve ispart of 112 hectares (277 acres) of coastal dune and wetland complex on thenorthern shore of Maui that has been under imminent threat of development as agolf course. The Maui Coastal Land Trust has arranged to purchase the WaiheèPreserve through funding from the County of Maui, U.S. Fish and Wildlife ServiceCoastal Wetlands, and Endangered Species grants from private donations. TheMaui Coastal Land Trust will restore and premanently protect 101 hectares (250acres) of this wetland complex, which encompasses 9.7 hectares (24 acres) ofwetlands, 41.7 hectares (103 acres) of buffering sand dunes, and approximately 3.2hectares (8 acres) of riparian habitat (Maui Coastal Land Trust 2003). WaiheèPreserve provides habitat for the Hawaiian stilt and coot.

Hawaiì

Keànae Pond (Keaàu) - Keànae Pond, located in eastern Hawaiì, is a spring-fedpond with connection to the ocean that has been altered through construction of ashoreline rock and wall and gate system. Hawaiian coots have been observedutilizing the marsh edge and some areas of the pond are suitable for loafing andfeeding. Long-term protection and management should be encouraged throughcooperative agreements between the landowner and natural resource agencies shouldbe encouraged. Vegetation management and predator control are needed to enhancehabitat for waterbirds.


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Kona Sewage Treatment Plant - The County of Hawaiì has designed man-madewetlands for Hawaiian stilts at the Kona (Kealakehe) Wastewater Treatment Plant. Ponds will be constructed with predator fencing and nesting islands for stilts, anddesigned to allow public access, with a parking area and interpretive trails and signs. Support by resource agencies to the county should continue and future projectsshould be encouraged that incorporate wildlife habitat enhancement and the needs ofthe county.

Montane (Mauna Kea and Kohala) and Parker Ranch Stock Ponds - Several pondslocated on the slopes of Mauna Kea and in the Kohala Mountains are owned byState, Federal, and private landowners, including Parker Ranch. These pondssupport most of the reproducing population of the Hawaiian duck on the Big Island.Protection and enhancement of these ponds should be accomplished throughcooperative efforts between agencies and private ranchers leasing the lands. DucksUnlimited has been actively working with the Natural Resources ConservationService to pursue these opportunities.

`Æpaeùla Pond - This 3-hectare (7.5-acre) privately-owned coastal pond is locatedin the North Kona District. Habitat for waterbirds on this site may be improved withvegetation management.

Waipio Valley - Waipio Valley is located in Hawaiì’s H~m~kua District, along thenortheastern coastline of the Kohala Mountains. Several tributaries flow intoWaipio Stream, but some are diverted by smaller ditches that feed taro fields. Thecentral valley is dominated by taro fields, while the lower valley is marshland. Thetaro fields and the large pond at the north edge of the lower valley provide waterbirdhabitat. The Hawaiian duck and coot utilize this site. Long-term protection andmanagement should be encouraged through cooperative agreements between thelandowner and natural resource agencies. Extensive management of wetlands in thelower valley is needed, particularly extensive clearing of invasive wetlandvegetation, creation of water impoundment areas, and effective water levelmanipulation.


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APPENDIX C. Comprehensive List of Wetlands.

Niìhau wetlands Protected Corewetland

Supportingwetland

`Âpana ReservoirH~ào DamHal~liì DitchesHal~liì LakeHalulu LakeKahino PondKamalino PondKaununui PondsKeanauhi DamKièkiè PondsL‘àhi PondMakahauèna PondNonopapa PondsPalikoae PondsPohueloa Valley PondPuù Àlal~ PondPuù Wai PondPlaya Lakes X X


139

Kauaì wetlands Protected Corewetland

Supportingwetland

Ààka ReservoirAepo ReservoirAepoalua ReservoirAepoeha ReservoirAepoekolu ReservoirAhukini ReservoirAii ReservoirAlexander ReservoirDe Mello ReservoirFern Grotto ReservoirGrove Farm Settling Basin (new)Grove Farm Settling Basin (old)Halen~nahu ReservoirHanalei National Wildlife Refuge X XHanalei Taro Fields (includes PostOffice Taro Fields, Hanalei TraderTaro Fields)

X

Hanalei River XHanam~ùlu Air Strip ReservoirHanap‘p‘ Salt Ponds XHanap‘p‘ Taro FieldsHanini Reservoir Huinawai Reservoir Hukiwai ReservoirHuleìa National Wildlife Refuge X XHuleìa Stream ValleyIoleau ReservoirIpuolono Reservoir Kaloko Reservoir Kaheluniui ReservoirKailiiliahinale (Okinawa)Reservoir Kalihiwai ReservoirKalihiwai River Estuary Kanaele SwampKanehu Reservoirs Kaneha ReservoirKapa ReservoirKapaà Stream Estuary Kapaia Reservoir Kaumakani Gulch Ponds Kaupale ReservoirKawaièle Waterbird Sanctuary X XKawaièle Sand MindKauaì Lagoons WestinKawailoa FlatsKekaha Pasture (dried up)


140

Kauaì wetlands (continued) Protected Corewetland

Supportingwetland

Kekaha Settling Basins (dried up)Kekaha Landfill (Leachate) PondKekaha Slaughterhouse Reservoir Kekaha Sugar Company SettlingBasinKîlauea Stream Estuary

Kîpû Reservoirs 1-4Kîpû Road ReservoirKolo Reservoir Kôloa (Kukuiùla) Sewage PondKoloakapohu Reservoir Kuhumu ReservoirKumano ReservoirL~waì Kai Estuary Lîhuè Settling Basin Lono Reservoir Luawai ReservorLumahai Wetlands X XM~h~ùlepû PondsM~n~ Base Pond X XM~n~ Ditches and Drains M~n~ House Reservoir M~n~ Ridge ReservoirM~n~ Wetlands XManuhonuhonu Reservoir Mauka Reservoir Menehune Fish PondMorita Reservoir Niu Valley ReservoirNiumalu Reservoir Nonopahu ReservoirOlokele Settling Basin `Æma'o Reservoir `Æpaekaà Marsh XP~puaà Reservoir Smith's Tropical Paradise(Paradise Pacific)

X

Pia Mill Reservoir Pilaà wetlandsPoa MarshPoìpû Ponds / AreaPoòpueo ReservoirPrinceville Golf Course Ponds Pukaki ReservoirPuù Ainako Puù Ka Ele Reservoir


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Kauaì wetlands (continued) Protected Corewetland

Supportingwetland

Puù O Hewa Reservoir Puù O Papai Reservoir Puù Opae ReservoirPuùhi Crater Reservoir Puùlani ReservoirReservoir 429Rodriques Reservoir 296 (defunct)Saki Mana Reservoir Sloggett (Wailua) ReservoirTwin Reservoirs Ùmi Reservoir U.S. Navy Sewage TreatmentPondWaiakalua Reservoir Waiawa ReservoirWaikai ReservoirWaikoloi ReservoirWailau Siphon Reservoir Waimea River System XWailua River Bottoms XWailua Jail Swamp Wailua Golf Course PondWaimea Heights Reservoir Waimea Taro FieldsWainiha Taro Fields and River XH~èna MarshWaioli Taro Fields/ StreamWaiopili Spring ReservoirWaip~ Taro Fields Wait~ Reservoir XWakai ReservoirWilcox Ponds


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Oàhu wetlands Protected Corewetland

Supportingwetland

Air Strip Ponds, KahukuAmorient Aquafarm (Romey's andMing Dynasty)Apokaà Ponds 1and 2 Barber's Point Golf Course PondsBellows Air Force Base Canal Chevron - Rowland Pond Chevron Impounding Basin Coconut Grove Marsh Crowbar Ranch Pond Diamond Head MarshDillingham Ranch Ponds Fort Kamehameha Reef Flats Haleìwa Lotus/Taro Fields XHalekou WetlandH~m~kua Marsh State WildlifeSanctuary

X X

Hawaiì Prince Golf Course Ponds Heèia Marsh X XHelemano ReservoirsHonolulu Airport Reef RunwayWetlandsHonouliuli Golf Course PondsHoòmaluhia Park Ponds(Botanical Park)James Campbell NWR (Kii andPunamano Units)

X X

Kaàlaea Aquafarm PondsKaàwa wetlands Kaèlepulu Mitigation Wetland Kahana Marsh (Huilua Pond) Kahuku Aquaculture Farms XKalou Marsh (University ofHawaiì Waialeè Station Pond) Kaneshiro's Lotus FieldsKapolei Golf Course Ponds (EwaPonds)Kawainui Levee Kawainui Marsh X X


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Oàhu wetlands (continued) Protected Corewetland

Supportingwetland

Keèhi Lagoon (Mudflats)Ko Olina Golf Course Ponds Kualoa Aquafarm (University ofHawaiì Mariculture ResearchCenter)Kualoa State Park Pond (ApuaPond)

X

Kuapa Pond, Hawaii KaiKuilima (Turtle Bay) SewageTreatment Pond

X

Kuilima Mitigation Pond (TurtleBay Mitigation Pond)L~ìe Wetlands XLaulaunui Island Fish Pond (NavalReservation)

X

Loko Ea PondLualualei Rubber-lined Pond XMakaha Golf Course PondsMakaha Sewage PondMarine Corps Base KaneoheKlipper Golf Course Ponds

X

Marine Corps Base SewageTreatment PlantMokuleia Quarry PondMoliì Fish PondNakatani watercressNiuliì Ponds, Lualualei XNuùanu Reservoirs 1-4 Nuùpia Ponds Marine Corps BaseHawaii

X X

Olomana Golf Course PondsOneawa CanalÒpaeùla Reservoirs 1-5Paiko Lagoon Wildlife Sanctuary X XPC WatercressPearl Harbor NWR (Waiawa andHonouliulu Units)

X X

Pouhala Marsh X XPunahoòlapa Marsh XPunaluù Prawn FarmRanch Camp Ponds


144

Oàhu wetlands (continued) Protected Corewetland

Supportingwetland

Sag Harbor Wetlands MarineCorps Base Hawaii

X

Salt Lake (Honolulu) CountryClubSalvage Yard Wetlands MarineCorps Base Hawaii

X

Steamer's LotusSumida WatercressTantog's LotusTurtle Bay Golf Course Ponds Ùkoà Marsh Unisyn PondUniversity of Hawaii ExperimentStation Ponds Wahiawa ReservoirWaialua Lotus Fields XWaialua Settling pondsWaiheè Marsh XWaikane Aquaculture PondsWaikele Harbor Mudflat Waimaea Falls Aboretum Waim~nalo ReservoirsWaipiò Pensinsula, Pear HarborShorelineWaipiò Settling Basins Waipiò Soccer Field WetlandsWalker's Bay Wetlands, WaipioPeninsula


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Molokai wetlands Protected Corewetland

Supportingwetland

H~lawa River Estuary Hawaiì Research FlatsKakahaià National WildlifeRefuge

X X

Kalua Koi Golf Course Ponds Kaluaàpuhi Fish Pond

Kamahuehue Fish PondKamalo Flats Kaunakakai Sewage TreatmentPond

X

Kaunakakai StreamKualapuù Reservoir XKupeke Fish PondMaunaloa Sewage Treatment PondMolokai Playas Moòmi Æ` ôìa Fish Pond `Æhiàpilo Wetland X XOliwai Sewage Treatment PondOne Aliì Fish PondPaialoa Fish Pond XP~l~àu Flats

L~naì wetlands Protected Corewetland

Supportingwetland

L~naì City Oxidation Ponds XHulopoè Mud Flats M~nele Oxidation PondsM~nele Road ReservoirManele Mud FlatsKôèle Golf Course Ponds


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Maui wetlands Protected Corewetland

Supportingwetland

Ahihikinau NAR XAirport Drainage DitchAzeka Pond 1Azeka Pond 2Cement HouseCrater ReservoirCrater VillageCut Mountain Settling PondH~liìmaile Treatment PondHale Nanea Drainage PondHaluaK~ànapali Golf Course PondsKahului Drainage DitchKahului Fairgrounds DrainageKahului Oxidation Pond Kahului Sewage Treatment PondKahului Settling PondKanaha Pond Wildlife Sanctuary X XKaneaka PondKapalua Bay Golf CourseKapalua ReservoirKapalua Village Golf CourseKauhi KauhioaiakiuiKealia Pond National WildlifeRefuge

X X

Keanae Point XKmart DitchLahaina Aquatic CenterLahainalunaLahaina Settling PondsLaniapokuLittle Pond Longs PondsMâkena Golf CourseMaluaka PondMauna Lani Golf CourseMill PondNuù Pond XOlowalu Reservoir 1Olowalu Reservoir 2Ômaòpio ReservoirPaia Settling PondPaniaka PondPioneer Crater ReservoirPuù Aliì PondPuù Kolii Reservoir 1


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Maui wetlands (continued) Protected Corewetland

Supportingwetland

Puù Kolii Reservoir 2Puù Kolii Reservoir 3Puù Nçnç Settling Basin (70,71)Reservoir 20Reservoir 21Reservoir 22Reservoir 23Reservoir 26Reservoir 29Reservoir 32Reservoir 33Reservoir 35Reservoir 40Reservoir 42Reservoir 50Reservoir 51Reservoir 52Reservoir 60Reservoir 61Reservoir 70Reservoir 72Reservoir 80Reservoir 81Reservoir 82Reservoir 84Reservoir 92Ukumehame Reservoirs 1-2Ukumehame Settling PondUkumehame Target RangeVIP Drainage DitchWaiàle ReservoirWaiheè Wetlands (WaiheèPreserve)

X

Waineè Settling Ponds


148

Hawaiì wetlands Protected Corewetland

Supportingwetland

Ahn's PondÀimakap~ Pond, Kaloko-Honokôhau National HistoricPark

X X

Ànaehoòmalu PondBaker Paddock PondsCyanotech HonoapuHonokôhau ReefKaàluàluKaloko Pond, Kaloko-Honokôhau National HistoricParkKapulehu PondsKealakehe (Kona) SewageTreatment Pond

X

Kealakekua Bay Pond Keànae or Keaàu Pond XKeanakolu Road Stock PondsKehena Pond 1Kehena Pond 2Kehena Pond 3Kehena Pond 4Kehena Pond 5Kehena Reservoir Kohala Stock Ponds XKokoiki ReservoirLahuipuaa PondsL~l~kea ReservoirL~l~kea StreamLoko Waka Pond XMauna Kea Stock Ponds XNakagawaOld Kahua Pond`Æpaeùla Pond XP~iìakuli ReservoirPololû River Valley Puakea ReservoirPunaluù PondPuù Iki PondPuù Kapu ReservoirPuù Lio`lio PondPuù Mauna Pond Puù Oo Ranch Stock PondsPuù Pûlehu ReservoirRaley's Pond


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Hawaiì wetlands Protected Corewetland

Supportingwetland

Slatter PondTribble PondWai~kea Pond XWaikoloa Golf Course PondWailoaWaimanu Valley Waipiò Valley XWaipuhi Pond 1Waipuhi Pond 2


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APPENDIX D. Endangered and Threatened SpeciesRecovery Priority Number Guidelines*

Degree ofThreat

RecoveryPotential

Taxonomy Priority

High

High

High

High

Low

Low

Low

Monotypic genus

Species

Subspecies

Monotypic genus

Species

Subspecies

1

2

3

4

5

6

Moderate

High

High

High

Low

Low

Low

Monotypic genus

Species

Subspecies

Monotypic genus

Species

Subspecies

7

8

9

10

11

12

Low

High

High

High

Low

Low

Low

Monotypic genus

Species

Subspecies

Monotypic genus

Species

Subspecies

13

14

15

16

17

18

* adapted from Listing and Recovery Priority Guidelines (1983), Federal Register 48:43098-43105


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APPENDIX E. Hawaiì Waterbird Count Instructions

Hawaiian Stilt:• Record the numbers of adults and juveniles separately if possible.

Juveniles can be distinguished by the white that extends farther onto theforehead and sides of the neck, the duller pink leg color, and their higher-pitched calls. Juveniles cannot be distinguished by back color; male stiltshave black backs, females and juveniles have brownish-black backs.

• Do not separate male and female stilts; count both as adults.• Check stilts for bands and record any band combinations. For example,

red over aluminum on left leg, green over yellow on right leg, or RA/GY. Right and left are always from the bird’s perspective.

Hawaiian Coot:• Record the numbers of adults and juveniles separately. Juveniles are light

gray and lack the white frontal shield of adults.• Do not separate coots by frontal shield coloration. Hawaiian coots can

have red or white frontal shields.

Hawaiian Moorhen:• Record the numbers of adults and juveniles separately. • Moorhens can be secretive and may not be visible right away. The

chances of observing moorhens and obtaining a more accurate count willbe improved if more time (at least 15 minutes) is spent watching quietly ateach site.

Koloa or Hawaiian Duck:Koloa are very similar to female mallards, but many birds can be distinguished bycareful observation of the characters described in the table below. Koloa-Mallardhybrids are intermediate but variable, and individuals may exhibit characteristicsof both species. Outside Kauai and parts of the Big Island, many ducks thatsuperficially appear to be Koloa may actually be hybrids. Male Mallards inbreeding plumage have a completely green head, white collar, chestnut breast,and gray back. Male mallards in non-breeding plumage and young males areduller in color and more similar to female mallards and to koloa, but show hintsof the adult male breeding plumage- head suffused with green especially on thecrown, breast feathers chestnut with dark tips, grayish back and sides, and adistinctive olive-green bill. Hybrid males often show some of the characteristicsof male mallards, especially a grayish back, whitish tail, and blue speculum.


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Character Koloa Female MallardSize Small; 70-80% length of Mallards.

Males 600 g, females 460 gLarge; males 1240 g,females 1080 g.

Bill size Smaller, narrower Larger, widerBill color Mostly dark, often greenish, tip of bill

may be orange in femaleMostly orange, with somedark splotches in center

Tail andundertailcovert color

Mottled brownish whitish

SpeculumColor

Emerald green (may appear bluish insome light)

Blue

Migratory Shorebirds. Record the number of each species of migratoryshorebird. If you are unable to identify a shorebird to species, take notes on itsappearance and behavior that can be used later to help identify it, includingrelative size (e.g. smaller than a Kolea, but larger than a Sanderling), bill length(e.g. bill 1.5 times length of head), leg length (e.g. legs longer than bill),coloration of different body parts (legs, head, back, eye-stripe, breast, whetherbreast is streaked), behavior (e.g. walking on exposed mud, wading in shallowwater, probing with bill, describe any vocalizations). The most frequentlyobserved species are briefly described below, for other species consult fieldguides.

• Pacific Golden Plover or Kolea. You should at least know this one!• Black-bellied Plover. Similar to Kolea but slightly larger and heavier,

with larger bill, and more gray plumage. In flight has black axillaries(wing-pits).

• Semipalmated Plover. A small plover with orange legs and a single darkbreast band.

• Ruddy Turnstone or Àkekeke. Smaller than Kolea. Back mottled brown,black marks on breast. Bill short and straight. Legs orange. Distinctiveblack and white back pattern in flight.

• Sanderling or Hunakai. Small. Bright white below, pale gray above,black legs, short straight bill.

• Wandering Tattler or Ùlili. Plain gray above, white below (may havedark barring in summer), narrow white stripe above eye. Legs mediumlong and yellow. Bill medium long and straight.

• Long-billed Dowitcher. A little larger than a Kolea, stocky, mostly gray,bill straight and very long. Often forages in slightly deeper water withrepeated “sewing machine” probes of the bill.

• Lesser Yellowlegs. More slender than Kolea, speckled gray-brownplumage. Legs long and yellow. Bill medium-long, thin, and straight. Often very active when foraging.


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• Pectoral Sandpiper. A little smaller than a turnstone, yellowish legs, billmedium length, sharp border between dense brown streaking on upperbreast and white lower breast.

• Sharp-tailed Sandpiper. Like Pectoral Sandpiper, but breast streaking lessdistinct, lower border more gradual, white stripe above eye (supercilium)more obvious, becomes wider behind eye.

• Bristle-thighed Curlew or Kioea. Large, brown, with long curved bill. Loud “kee-oo-eet” call often given in flight.

Migratory Waterfowl. Record the number of each species of migratorywaterfowl. Migratory waterfowl are not usually present during the summercount. If you are unable to identify a duck, goose, or some other species ofwaterfowl, take notes on its appearance and behavior that can be used later to helpidentify it, including bill shape, coloration of different body parts (head, breast,sides, speculum), behavior (dabbling on surface, diving under water). The mostfrequently observed species are briefly described below, for other species consultfield guides.

• Canada Goose. Black neck with white cheek patch. Recently split into 2species, best distinguished by size and bill length. Presence of white neckring may help identify some forms. Take photographs if possible.

o Canada Goose. Larger, longer-billed, generally paler, typical“honking” call.

o Cackling Goose. Smaller, shorter-billed, darker on the breast andback, higher-pitched “cacking” call.

• White-fronted Goose. Grayish-brown with black marks on breast, whiteon face at base of pink bill, orange legs.

• Northern Pintail. Long and slim with pointed tail. Breeding males havebrown head, white breast and neck stripe, nonbreeding males and femalesare speckled brown all over. Neck and tail longer than other ducks.

• Northern Shoveler. Long, flat, orangish bill is distinctive. Breedingmales have green head, white breast, chestnut sides, nonbreeding malesand females are brownish.

• American Wigeon. Males have green head with whitish forehead. Females brown. White patch on upper wing distinctive in flight.

• Teals. 3 species, all are small.o Green-winged Teal. Green speculum, bill small. Breeding males

have green and chestnut head, vertical white stripe on side. Infemale dark line through eye more distinct than Blue-winged andCinnamon.

o Cinnamon and Blue-winged Teal. Large blue patch on upperwing. Breeding male Cinnamon Teal mostly cinnamon, breedingmale Blue-winged Teal has dark head with white crescent in frontof eye. Females and nonbreeding males hard to separate, consult


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field guides.

• Lesser Scaup. Dives under water. Males have dark head, breast, and tail,gray back and sides. Females brownish with white patch at base of bill.

• Ring-necked Duck. Dives under water. Male has dark head, back, breastand tail, gray sides. Bill dark with white band near tip. Female dark withwhite eye ring and white at base of bill.

Feral Waterfowl. Several species of ducks and geese have been introduced toHawaii and have become feral. Please note the presence and numbers of feralwaterfowl. The most widespread species are briefly described below. Consultfield guides for other species.

• Mallard. Males have green head, chestnut breast, and white neck ring;females brownish and streaked. Some wild Mallards may migrate toHawaii; feral birds are usually less wary than wild birds, and feralMallards are often larger.

• Muscovy. Large, black and/or white ducks with knobby red bill.• Domestic ducks. Color variable; some are white with a yellow bill

(“Peking” duck), some look like oversize mallards.• Domestic geese. Large, long neck, color variable; some are gray with an

orange bill, some are all white with an orange bill.

Other Information to Record:1. Time each area was surveyed, wetland condition, and weather, using

codes provided on field forms.2. Any unusual habitat observations or anything inconsistent with

previous waterbird surveys.3. Note location and approximate size of any Cattle Egret roosts.

Other Issues:• Wetland names. One of the biggest challenges in compiling and

analyzing the waterbird count data has been inconsistent use of names. We need to produce a master list of wetland names, including allsynonyms that have been used for each site, and choose one name touse for each wetland from now on.

• If at all possible, try to visit all wetlands on the scheduled itinerary. Ifyou know in advance that a particular wetland no longer exists andthere is no point in visiting it, make a note of it when submitting formsso that information can be recorded into a wetland database.

• Fill out a data sheet for each wetland you visit, even if no birds arepresent or the wetland appears dry. If no sheet is filled out andsubmitted, it may be assumed that the site was not visited that year.


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• For wetlands with subsites (e.g., Kealia Pond, Kanaha Pond, KaneoheMarine Base), record data separately for each individual subsite. Datafrom different subsites can be combined later if necessary, but if data islumped when collected, we cannot separate it later.

• Copies of the data sheets should be kept by the compiler on each island,even after they have been submitted to the Oahu office. In some casesthe data appears to have been lost in the DOFAW office on Oahu (orperhaps never received?), and the original data sheets could not belocated. It is very unfortunate to lose this irreplaceable data afterpeople have made the effort to collect it.

Revised January 2005. If you have comments or suggestions for improving the field form, theinstructions, or the count in general, please contact Eric VanderWerf of the U.S. Fish andWildlife Service ([email protected]; 792-9461), David Smith of the Hawaii Division ofForestry and Wildlife ([email protected], 973-9786), or Megan Laut of the Hawaii NaturalHeritage Program ([email protected]).

Region 1U.S. Fish and Wildlife ServiceEcological Services911 NE. 11th AvenuePortland, Oregon 97232-4181

May 2005

Documents

U.S. Fish & Wildlife Service Draft Revised Recovery …...Second Draft Revised Recovery Plan for Hawaiian Waterbirds, 2nd Revision • May 2005 ii Acknowledgments Parts I and II of