Proceedings of the Ninth Mountain Lion Workshop - Carnivore ...

Using DNA to Estimate Cougar Populations: a Collaborative Approach
Richard A. Beausoleil, Washington Department of Fish and Wildlife, 3515 State
Highway 97A, Wenatchee, WA 98801, USA, beausrab@dfw.wa.gov
Kenneth A. Warheit, Washington Department of Fish and Wildlife, 600 Capitol Way
North, Olympia, WA 98501-1091, USA, warhekiw@dfw.wa.gov
Wan-Ying Chang, Washington Department of Fish and Wildlife, 600 Capitol Way North,
Olympia, WA 98501-1091, USA, changwyc@dfw.wa.gov
Donald A. Martorello, Washington Department of Fish and Wildlife, 600 Capitol Way
North, Olympia, WA 98501-1091, USA, martodam@dfw.wa.gov
John D. Pierce, Washington Department of Fish and Wildlife, 600 Capitol Way North,
Olympia, WA 98501-1091, USA, piercdjp@dfw.wa.gov
ABSTRACT To better understand population dynamics of cougar, agency managers need
long-term data sets collected using standardized methodologies. Short-term studies,
while useful for management, are only “snapshots in time”, and provide little information
about year-to-year variability or long-term status. Nonetheless, wildlife agencies are
typically only able to conduct population estimation projects for 5 years or less because
of expenses associated with current research methodologies. The objectives of this
project were to: (1) acquire a scientific population estimate of cougars in northeast
Washington; (2) test the efficacy and practicality of using DNA capture techniques to
estimate cougar population size; (3) manage project costs to allow agencies interested in
the technique to potentially conduct the research for decades. We used a capturerecovery
methodology but instead of using conventional markers (i.e., radio collars,
eartags and tattoos), we used DNA from tissue samples collected from treed cougar as
our “capture” and DNA samples collected from harvested cougar as our “recovery”. We
tested 5 biopsy dart types from 3 different manufacturers to collect the samples from
treed cougars. For the “capture” sample, volunteer hound handlers were deployed
throughout the project area between 01 November and 31 December (2003-current) to
tree cougars using hounds and obtain a DNA sample via a biopsy dart and CO2 powered
rifle. There was no physical handling required and once a sample was retrieved, the
cougar was immediately left in the tree. Each hound handler was assigned to a specific
portion of the project area and each was required to work 20-25 days within the allotted
timeframe. The “recovery” phase immediately followed the “mark” period (01 January
to 31 March) each year. During the hunting season agency personnel collected a tissue
sample from all cougar mortalities statewide via a mandatory reporting system. DNA
from both samples was analyzed using micro-satellite analysis. The DNA fingerprint
analysis consisted of positively identifying 28-36 alleles (14-18 loci) for each tissue
sample. Samples that did not produce a minimum of 14 loci were censored. We
extracted the specified number of loci from 128 of 163 cougar samples resulting in
identification of 100 individual cougars in the “capture” sessions. In the “recovery”
sessions, over 62 tissue samples were collected and analyzed from within the project
area. Sixteen of the 62 recoveries were previously “captured”. We used Program MARK
to estimate population size, which resulted in an average within-year population estimate
of 43 cougars (CI 34-58) or 0.87 (CI = 0.65-1.1) cougars per 100km 2 . Over the 4 years, it
appears that the cougar population has declined. The cost of the DNA project in year 1
was $24,110. However because that included microsatellite plates (a one-time expense)
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