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COPELAND HIGHWAY PROJECT
STUDY AREA
> Purcell Mountains> 16 miles of Highway 95> 300 km2 > Pacific maritime climate> Elevations range from 540 to 1950 m> Forested with active timber management> Huckleberries and buffaloberries
STUDY AREA
> 3 underpasscrossing structures
2004
3 Objectives
Has highway been a genetic barrier (from B.O.)?
Is highway a movement barrier (from B.O.)?
Are animals using the underpasses?
Has Highway been a Genetic Barrier?
• DNA from 197 different bears (hair snare and trapping)
• Fst = 0.0119 (very low level of genetic divergence)
• At least 3 migrants per generation.
There is no current evidence that the highway has acted as a genetic barrier.
Is highway a physical movement barrier?
RESULTS
Highway as home range boundary
BLACK BEAR SPACE USE
RESULTS
Female black bear
Home range centeredover Highway
14 Highway crossings
Human Development
BLACK BEAR SPACE USE
Is Highway a Movement Barrier?
• Almost half of all radio-collared black bears crossed the highway at least once.
• 2 of 3 radio-collared grizzly bears crossed the highway.
• At least 3 migrants per generation (from DNA work).
At current traffic volumes, highway is not a movement barrier.
Are Animals Using the Underpasses?
• Short Answer: Yes
Are Animals Using the Underpasses?
Longer Answer Underpass
Species #1 #2 #3 TotalBlack Bear 11 3 14Bobcat 1 2 3Cat 5 5 9 19Coyote 8 14 7 29Dog 1 2 3Elk 12 3 15Hare 45 9 8 62Moose 1 1 2Packrat 1 2 3Racoon 3 5 7 15Skunk 2 1 3Squirrel 3 2 5Swallow 2 5 2 9WT Deer 450 117 30 597
Grand Total 545 167 67 779
Underpass Use: Time of Day
Lies, Damned Lies, and Statistics
Liars, Damned Liars, and Scientists
Probability of crossing in relation to habitat variables
Model R2 Delta AIC__________________________________________________
HumDev 0.308 0HumDev CanCov 0.309 1.81HumDev Water 0.308 1.92HumDev CanCov Water 0.309 3.80CanCov 0.054 24.06Water 0.0019 28.15
y = -17.915x - 13.946
R2 = 0.3076-50
-45
-40
-35
-30
-25
-20
-15
-10
-5
0
0 0.2 0.4 0.6 0.8 1 1.2
Proportion of Human Development
Lo
g P
rob
ab
ilit
y
y = 12.98x + 12.43
R2 = 0.231
0
100
200
300
400
500
600
700
800
900
1000
0 5 10 15 20 25
PDOP
Lo
catio
n E
rro
r (m
)
Time of Day
Conclusion: Deer use underpasses most in the morning and evening and less during the day.
Conclusion: WTD use underpasses less during the day, but not different than expected during other time periods (p<0.00).
Time of Day
Time of Day
Time of Day
Problem: Variable sunrise/sunset.
• Obtained sunrise / sunset tables.• Used “nautical twilight” to define dusk/dawn
– General outlines may be distinguishable but detailed outdoor operations are not possible; horizon indistinct
– sun 120 below horizon; here equals 1 hr 3 min
• Dawn: + 1 hr 3 min of sunrise• Dusk: + 1 hr 3 min of sunset
Time of Day
Time of Day
Conclusion: Deer use underpasses most at night and least during dawn.
Time of Day
Observed Expected
Dawn 87 46
Day 127 229
Dusk 133 46
Night 203 229
Chi-square test Compares “Observed” versus “Expected” occurrence. Allocate “Expected” based on length of each time period.
Time of Day
Conclusion: Dawn and Dusk are used more than expected, Day is used less then expected, and Night is used as expected (p<0.000).
Beware of Liars, Damned Liars, and Scientists
...But mostly Scientists.