Tribes sample elk DNA to track population

 

Wildlife biologists from Stillaguamish, Tulalip and Western Washington University sample DNA from elk scat.

Wildlife biologists from Stillaguamish, Tulalip and Western Washington University sample DNA from elk scat.

Northwest Indian Fisheries Commission

 

Wildlife biologists from the Stillaguamish and Tulalip tribes are testing a new way to track the population of the Nooksack elk herd using the animals’ scat.

Tribal biologists have partnered with Western Washington University’s Huxley College of the Environment to determine the most efficient way to collect DNA from elk scat. Genetic material can be found in the intestinal mucus coating the pellets. This winter, biologists sampled fresh scat using toothpicks and cotton swabs, submitting the samples to a genetics lab to determine which method is most effective at providing an animal’s unique genotype.

“This is a non-invasive method that does not require collaring animals or helicopter time to survey them,” said Stillaguamish biologist Jennifer Sevigny.

While the current method of using tracking collars and aerial surveys is expensive, it allows state and tribal wildlife managers to determine the bull-to-cow and cow-to-calf ratios needed to set harvest levels. To fit elk with tracking collars, the animals must be captured and tranquilized.

In the spring, the Stillaguamish and Tulalip tribes plan to coordinate a large population survey, sampling elk scat in the North Cascades Mountains, including forested landscapes that are hard to monitor during aerial surveys.

“Once individual elk are identified by their DNA, a population estimate can be obtained by re-sampling an area and comparing the number of originally identified individuals – the marked animals – to the newly identified animals – the unmarked animals,” said Tulalip wildlife manager Mike Sevigny.

During the past two decades, tribal and state co-managers completed numerous habitat restoration projects to improve forage for the Nooksack herd, which had declined to about 300 animals by 2003. According to 2012 aerial surveys, the herd has rebounded to as many as 1,400 elk.