Habitat mapping in Ninigret Pond, a shallow coastal lagoon in Charlestown, R.I.

Side Scan Sonar Mosaic Color-coded map of differing patterns

Video Ground-Truthing 2004 2003

Sediment Profile Images

Match bottom types to video Map video observations Match bottom types to video Map video observations

Results

The goal of this study was to identify eelgrass beds and their neighboring habitats in Ninigret Pond. Underwater video and sediment profile images were used to verify the findings of the physical surveys of the bottom (bathymetry and side scan sonar), and to characterize the biology of each habitat. Now that the important eelgrass habitats have been identified, it is critical to study which organisms are using this habitat and how. While the underwater video provided a general view of vegetation types, the sediment profile images will prove to be a rich source of data for organism identification, abundance, and overall habitat health. Certain organisms serve as indicator species to researchers, representing the health of their habitat and whether it is improving or degrading. A biological sampling survey is necessary to identify these organisms and determine the structure of the communities in which they live. By achieving a greater understanding of habitat dynamics, researchers will be able to recognize and effectively monitor potential problems within the habitat.

Acknowledgements

References

How are habitat maps used? •  Monitoring endangered or commercially valuable species

•  Measuring change in the environment due to human influence

•  Planning dock/marina location

•  Monitoring effects of pollution

Final Map

•  Brown, Jr., C (1962). The ecology of aufwuchs on Zostera marina in Charlestown Pond, Rhode Island. Portions of a thesis submitted to the University of Rhode Island: 55-58. •  Germano and Associates, Inc. (2004). SPI Fact Sheet. Internet resource last accessed: November 15, 2004. http://www.remots.com/SPI_Factsheet.pdf •  Nilsson, H. C. and R. Rosenberg (1997). Benthic habitat quality assessment of an oxygen stressed fjord by surface and sediment profile images. Journal of Marine Systems 11: 249- 264.

All data entered in an easily accessible GIS database

Discussion

•  Heavy boat traffic was evident by propeller scarring in areas of the pond >5 feet deep. These areas also did not contain eelgrass. B e c a u s e e e l g r a s s

survival is also dependent on light availability, water d e p t h o r b o a t s c a r r i n g

could be preventing eelgrass to grow in these areas of Ninigret Pond. •  Eelgrass was limited to the middle of Fort Neck Cove, Tockwotton Cove, and the Grassy Point area of the pond. •  Although the northwestern branch of Fort Neck Cove contained large

amounts of detritus or rotting material, it was biologically active (worm egg-

cases were observed). •  The west end of the pond consisted of muddy to shelly substrates with patches of algal growth. There was no eelgrass in the west end, but it was

prevalent at one time (Brown, Jr., 1962).

•  The URI Coastal Fellows Program is supported by the URI Offices of the President and Provost, and the College of the Environment and Life Sciences.

•  Additional funding provided by the RI Sea Grant BayMap Project.

•  Special thanks to Marine Research Specialist Carol Gibson and Shelter Harbor Society Intern Ezra Beaver.

Emily Shumchenia¹, Dr. Kathryn Ford², Dr. John King³ 1. URI Coastal Fellow 2. Postdoctoral Research Fellow, URI-GSO 3. Professor of Oceanography, URI-GSO

•  Planning eelgrass restoration projects

•  Site selection for shellfish seeding

Database Structure

Identify different patterns in the side scan records

CREATING THE HABITAT MAP Side Scan Sonar Analysis

Step 4: Sediment Profile Images •  SAIC REMOTS camera (Remote Ecological Monitoring Of The Seafloor) •  72 images at 21 stations •  Determine Benthic Habitat Quality (BHQ) index (Nilsson & Rosenberg, 1997)

Methods

Step 1: Bathymetry •  Location & depth readings •  54,516 data points recorded •  Contour map by Peter August

Step 2: Side Scan Sonar •  Edgetech Subscan system •  Recorded with Edgetech Discover v.2.49 •  Mosaic compiled in SonarWeb Pro v. 3.16 •  Bottom types color-coded in ArcMap 8.2

Narragansett Bay and the south-shore coastal lagoons in Rhode Island lack a comprehensive inventory of their geology, habitats, biological communities, and archeology. The BayMap project seeks to create such an inventory and map these physical and historical resources. A map of this type will be invaluable to scientists, environmental managers and government-funded organizations for use in monitoring programs, regulation of human activities, and even further study.

The first year of the six-year BayMap project focused in part on creating a habitat inventory for a shallow coastal lagoon, Ninigret Pond, located in Charlestown, Rhode Island. Ninigret Pond contains extensive eelgrass beds which serve as a valuable habitat for fish and shellfish. This poster illustrates the steps taken to identify the eelgrass beds and surrounding habitat types in Ninigret Pond, and to create a digital habitat map of these areas.

Introduction

Step 3: Underwater Video

•  Applied Microvideo M-225 underwater camera •  Sites chosen from color-coded side scan map •  Detailed log of observations with coordinates •  Mapped vegetation density and bottom types using observation log and locations

Step 4: Sediment Profile Images •  SAIC REMOTS camera (Remote Ecological Monitoring Of The Seafloor) •  72 images at 21 stations •  Determine Benthic Habitat Quality (BHQ) index (Nilsson & Rosenberg, 1997)

Bathymetry map Edgetech towfish

How the REMOTS camera works

(Germano & Assoc.)

data streams were recorded on a laptop running HypackMax version 2.2 oceanographic survey software.

In each of the four steps of data collection, navigation was collected with a Trimble DSM212L DGPS and depth was collected with a Garmin 240 echo sounder. The two

Sediment-water interface

Crab Ctenophore