A chest freezer at Montana State University holds more than 400 different hair samples, ranging from pale blond to jet black, from the grizzly bears of Yellowstone National Park. Some of them were collected recently, others are 25 years old. In a few months, they'll all be shipped to a lab called Wildlife Genetics International, in British Columbia, to determine if new DNA has been introduced into the population in the past few decades.
The hairs are usually plucked from a bear's shoulder region while it's being tagged with a radio collar, or after it's been found dead. Some samples are inadvertently snagged when a bear crawls under barbed wire.
Though the grizzly population in the Yellowstone ecosystem—about 550 to 600 bears—is double what it was 20 years ago, experts fear that it lacks genetic diversity. "We know it's low," Chuck Schwartz, head of the Grizzly Bear Study Team based at MSU, said in a press release. "There are concerns about inbreeding and other issues because we don't have new genes flowing into the system on a regular basis."
The genetic analysis team will compare the Yellowstone bear DNA to that of bears from the Northern Continental Divide (including Glacier National Park), where a similar study has already been done. In addition to giving an indication of how diverse the grizzly population is, the results will show whether bears from the Northern Continental Divide migrate to Yellowstone.