COUGAR ECOLOGY AND BEHAVIOR IN A WILDLAND-URBAN ENVIRONMENT IN

WESTERN WASHINGTON

Brian N. Kertson, Ph.D. Washington Department of Fish and Wildlife

HUMANS AS A LIMITING FACTOR

Habitat loss*

Competition for prey biomass

Disease Over-harvest

Social tolerance*

WASHINGTON AND PEOPLE

• Increasing human population

-WA 2030: 8.4 million

• Habitat loss

-WA: 27 km² per year

• High levels of interaction

COUGARS IN A RAPIDLY URBANIZING WORLD

1) Spatial ecology and behavior in the Wildland-Urban Interface and residential areas

2) Understand the role of cougar population characteristics in use of residential areas

3) Develop management recommendations

COUGAR WILDLAND-URBAN ECOLOGY

STUDY AREA

• 3,500 km2

• Topographically complex

• Densely forested, wet

• Gradient of residential development

Seattle

GPS COLLARS

• Vectronics GPS Plus-1D

• 6 fixes/day

• Globalstar satellite uplink or UHF download on demand

UTILIZATION DISTRIBUTION (UD)

SPATIAL ANALYSES

• Resource Utilization Functions (RUFs)

-Home range, wildland, and

residential

-Population and individual

• Movements rates (m/hr)

-Location, Time, L x T

Y = β0 + β1x1+ β2x2 + β3x3 + βnxn ……

WILDLAND-URBAN INTERFACE (WUI)

RESIDENTIAL USE

• Residential use common

• Overlap:

-93% of cats (n = 27)

Average:

-Volume = 16.86% ± 17.05

-Area = 18.35% ± 16.75

AVERAGE USE RELATIVE TO WUI

0

5

10

15

20

25

30

35

40

45

50

Sex Age Social

UD

Re

sid

en

tial

Ove

rlap

(%

) DEMOGRAPHIC CHARACTERISTICS

Male (n = 17)

Adult (n = 24)

Subadult (n = 9)

Resident (n = 21)

Transient (n = 12)

f1,28 = 0.6990, P = 0.41 f1,28 = 6.990, P = 0.01 f1,28 = 0.0004, P = 0.98

Female (n = 16)

INTERACTION RATE

• Marked cougars (n = 32):

-1.6 interactions per 1,000 radio days

• Adjusted rate:

-1.9 interactions per 1,000 radio days

• 2,323 observations ≤ 500 m from development:

-Interactions in 0.0073% of observations

WILDLAND VS. RESIDENTIAL SPACE USE

*n = 19 cougars, 24 cougar-yrs

MOVEMENTS

0

100

200

300

400

500

600

Diel Crepuscular Nocturnal

Mo

vem

en

t R

ate

(m

/hr)

Movement Period

Wildland

Residential

Time: f2,53 = 4.180, P = 0.02 Loc. : f1,53 = 1.141, P = 0.29 L x T: f2,53 = 0.500, P = 0.61

WILDLAND-URBAN ECOLOGY

• Adaptable

• Cover, prey, and connectivity

• Suitable habitat interspersed with development

• Use residential areas like wildlands

• Full suite of normal behaviors

• Low interaction rates → high coexistence

RESIDENTIAL THRESHHOLDS

Residential Density (km2)

Location n 50% CDF 95% CDF 99% CDF

Westside 14 0.890 177.6 846.0

Cle Elum 20 0.030 19.6 89.0

Okanogan 19 0.083 19.8 99.0

Northeast 15 0.113 2.6 9.9

*81.6% of use in areas < 1 residence/km2

COUGAR WILDLAND-URBAN ECOLOGY

• Cougars use of residential areas will continue:

-Connectivity, cover, and prey

• Cougars and people are coexisting

• Education and landscape planning is key

CARNIVORE CONSERVATION MUST BE MULTIDISCIPLINARY

Wildlife Professionals

Education and Outreach Landscape and Urban Planners

LANDSCAPE PLANNING

Low density, diffuse High density, concentrated

Kertson et al. 2011

PROPELLING COUGAR MANAGEMENT

…………..FORWARD

Do cougar population characteristics influence use of residential areas and

interactions with people?

POPULATION CHARACTERISTICS

• Vital rates

• Immigration/emigration

• Population growth

• Age structure

• Sex ratios

• Density

• 13 captures

-3 adult M

-3 subadult M

-4 adult F

-3 subadult F

• 85% use residential

F13

F4

F8

RESIDENTIAL USE

• Cougar space use

-Utilization distribution

• Residential vs. wildland

Measure overlap in ArcMap

(Kertson et al. 2013)

MANAGEMENT IMPLICATIONS

• Maintain cougar population viability and minimize risks

-How to manage pops in wildland-urban landscapes

-Improved outreach and education

• Cougars in wildland-urban landscapes

-Source or sink?

-Demographic or behavioral differences

STATISTICAL ANALYSES

• ANOVA fixed-effects

-Study area

-Period (pre/post closure)

-Study area x Period

• t – tests

-Population characteristics

• Multiple regression

-Residential use ~ population characteristics

NEXT STEPS

Questions?