With the help of experienced hound hunters, the Washington Department of Fish and Wildlife (WDFW) is collecting DNA samples from cougars in northeast Washington through the end of the year to learn more about the population of the big cats.
The study is a new "mark and re-capture" effort that does not use drugs or place equipment on animals, said WDFW bear and cougar specialist Rich Beausoleil. Instead, DNA is used to "mark" individuals that may be later "re-captured" during cougar hunting season. DNA comparisons will help develop better cougar population density estimates.
Beausoleil explained that selected and trained hound hunters are now seeking as many cougars as possible in the Sherman (101) and Okanogan East (204) Game Management Units (GMUs) in Ferry and Okanogan counties. When a cougar is treed by hounds, it is shot in the rump with a special biopsy dart that instantly obtains a small sample of skin and tissue. The dart falls from the cougar to the ground where it is retrieved, immediately stored in a protective vial, and sent to a lab for DNA analysis.
When cougars are killed during the public safety cougar removal permit hound hunting season that runs January 1 through March 15 in the study area, DNA samples are taken from those cats by WDFW officials during the mandatory pelt tagging procedure. DNA samples are also collected from all other cougar mortalities, including non-hound hunting season and depredation permit kills. Those samples are sent to a lab for analysis and a search for matches with earlier identified cougars.
From that data, Beausoleil said, a tried and true computer wildlife population modeling program generates the estimated number of cougars in the area.
"To put it simply, if we dart a lot of cats that don't show up later in the harvest then we know we likely have a large population," explained Beausoleil.
The use of DNA is preferred over tagging, collaring or other methods of marking individuals, Beausoleil explained, because the cougars are already marked by their DNA and the method is less intrusive to the animal.
The two northeast units were chosen for the study because they have some of the highest numbers of public safety cougar removal permits (GMU 101 has 12 permits, GMU 204 has 18.) Those permits are based on frequency of confirmed cougar complaints and problems during the prior year.
Beausoleil expects to have results from the study in the Spring so they can be used to refine cougar management next year.