THE EFFECT OF WILDLIFE CROSSING WIDTH ON CROSSING SUCCESS RATENWHA Conference 2018

Portland, OR

February 22, 2018

Steve Albertelli

PacifiCorp

PROSPECT NOS. 1, 2, AND 4 HYDROELECTRIC

PROJECT (FERC P-2630)

• Located in NW Jackson County, Oregon on the Middle Fork and North Fork Rogue River and Red Blanket Creek

• Four generating units w/ installed capacity of 41.56 MW

• 9.27 miles of Project waterways (canals, flumes, sag pipes, flowlines and penstocks)

• 24 pre-existing canal crossing opportunities, including six dedicated wildlife crossings (as of 2008)• Four 6’-wide crossings

• Two 12’-wide crossings

RELICENSING, CONSULTATION, AND REGULATORY CONTEXT

ODFW’s FPA 10(j) recommendations included 36’-wide crossings• PacifiCorp installed 36’-wide crossings at North Umpqua Project (License issued 2003)

• Primary focus on large, herd animals (i.e. elk)

FERC issues new license in 2008• Acknowledges that elk can cross existing 6’-wide crossings

• Requires PacifiCorp to evaluate 12’-wide crossings for effective passage and ultimately provide 10 large wildlife crossings of effective width (12’ or 36’)

STUDY DESIGN

• 3-year evaluation using camera traps “to gather information on large animal use and behavior upon approaching and using the crossings.”

• Upgrade 6’-wide crossings to 12’-wide

• Provides limited before-after data

• Consistency and focus on question of whether 12’ is adequate width

• Use of Reconyx PM75 Rapid Fire cameras mounted to observe both crossing approaches

• Monthly data collection

• Data processing and analysis

Before

After

CAMERA TRAP LAYOUT

CAMERA TRAP LAYOUT

DATA ANALYSIS

• Behavioral Response Categories

• Alarmed flight – elk approached and rapidly departed or crossed in an alarmed manner.

• Alert – elk assumes an erect posture, maintains a relatively fixed gaze, and struts in a stiff gait.

• Enter and retreat – elk entered the crossing approach but retreated away from the crossing.

• Feeding – elk were within the approach or on the crossing with head down and eyes on the ground instead of the direction of travel. Also includes head-up browsing of adjacent shrubs or trees.

• Standing or milling about – elk that stood or milled about the approach or crossing in a non-erect (i.e. non-alert) posture.

• Result Categories

• Did not cross – elk did not cross the canal. Often associated with alarmed flight and enter and retreat behaviors, although observations of elk travelling parallel to the canal (i.e. perpendicular to the crossing) were also assigned to this categorization.

• No delay – elk crossed with less than 10 seconds combined hesitation.

• Minor delay – elk crossed with 11 to 30 seconds combined hesitation.

• Obvious delay – elk crossed with more than 30 seconds combined hesitation.

DATA ANALYSIS: NO DELAY

DATA ANALYSIS

DATA ANALYSIS

• Single-file group movement• “Law of Least Effort” – V. Geist

• Particularly through snow

• Both in the open and on crossing structure

DATA ANALYSIS: ALERT, STANDING/MILLING ABOUT; OBVIOUS DELAY

DATA ANALYSIS: ALERT, ENTER AND RETREAT; OBVIOUS DELAY

DATA ANALYSIS

BULLS

BULLS

BULLS

IMPLEMENTATION OPPORTUNITIES AND CHALLENGES

• Subjective interpretation of behavioral cues

• Inability to isolate environmental factors

• Propensity of individuals for risk aversion• Skittish lead cows

• False triggers• Warm, wind-blown vegetation

• Data loss• Technical difficulties (batteries, CF card, etc.)

• Theft

• Vandalism

STUDY RESULTS - MAMMALIAN WILDLIFE SPECIES OBSERVED BY CROSSING AND CALENDAR YEAR (20XX)

Species MB4 WC1 WC3 WC4 WC6 WC7

American marten (Martes americana)

09 09

Black bear (Ursus americanus) 09,10,11 09,10 09,10,11 09 10 09,10,11

Black-tailed deer (Odocoileus hemionus columbianus)

09,10,11 09,10,11 09,10,11 09,10,11 09,10,11 09,10,11

Bobcat (Lynx rufus) 09,10 09 09 09,10 09,10,11 09,11

Chipmunk (Tamias sp.) 10

Common raccoon (Procyon lotor) 10 09 09,10,11 09,11

Cougar (Puma concolor) 09,10,11 09,10,11 09,10,11 11 09,11 09,10,11

Coyote (Canis latrans) 09,10,11 10,11 10,11 09,10,11 09,10 09,10,11

Elk (Cervus elaphus) 09,10,11 09,10 09,10,11 09,10,11 09,11 09,10,11

Golden-mantled ground squirrel (Spermophilus lateralis)

09

Gray fox (Urocyon cinereoargenteus)

09,10,11 09,10,11 09,10,11 09,10 09,10,11 09,10,11

Striped skunk (Mephitis mephitis) 10 10,11 10 09,10 09,10,11 09,10,11

Western gray squirrel (Sciurus griseus) 09,10 09 09,11 09,10,11 09,10 10,11

STUDY RESULTS – ELK OBSERVATIONS

MB4 WC1 WC3 WC4 WC6 WC7 Total

No Delay 15 2 5 55 10 27 114

Minor Delay 2 1 0 22 6 7 38

Obvious Delay 0 0 1 28 2 8 39

Did Not Cross 0 0 1 9 2 7 19

Total 17 3 7 114 20 49 210

Results of elk events by crossing location

MB4 WC1 WC3 WC4 WC6 WC7 Total

No Delay 85 7 31 124 13 29 289

Minor Delay 3 12 0 68 7 12 102

Obvious Delay 0 0 13 120 3 15 151

Total Crossed 88 19 44 312 23 56 542

Did Not Cross 0 0 1 22 2 9 34

Total Observed 88 19 45 334 25 65 576

Passage Rate 100.0% 100.0% 97.8% 93.4% 92.0% 86.2% 94.1%

Number of elk per result category and passage rates by crossing location

IMPLICATIONS AND AREAS FOR FURTHER STUDY

• Conclusions• (1) herds of large animals, specifically elk, will cross twelve-foot-wide wildlife crossings

• (2) the physical aspects of twelve-foot-wide crossings do not exert enough influence on elk to prevent successful canal crossings.

• Additional before-after data and controls• 12’ is not necessarily the magic number

• Effect of canal width on response to crossing width

• Prey-trap hypothesis is not supported by data

• Optimal crossing interval• By species, landscape position, etc.

• Number of crossings may be more critical than width

UP CLOSE AND PERSONAL

QUESTIONS