Thursday, October 25, 2007

Continental Divide Ecosystem Grizzly Estimate

GREAT FALLS, Mont. (AP) -- A study of grizzly bears in and around Glacier National Park estimates 240 of the bears live in a 2 million acre area. This is a 3,125 square mile area.

"It's the first really rigorous population estimate for that area," said Kate Kendall, a West Glacier-based research biologist with the U.S. Geological Survey, who led the study.

The Greater Glacier area includes the 1.1 million-acre national park plus 900,000 acres of surrounding grizzly habitat, including the Blackfeet Indian Reservation and lands west of Glacier to U.S. Highway 93. This arear is also known as the 'Northern Continental Divide Ecosystem'.

Researchers estimated the population by collecting bear hairs in 1998 and 2000 and analyzing the DNA in each strand. The estimate is important because grizzly recovery efforts can't be measured without reliable population figures, Kendall said.

In 1998 and 2000, researchers collected almost 15,000 bear hairs left behind at barbed wire "hair corrals" and natural bear rub trees evenly distributed across the 2 million acres. Individual bears can be identified from their hair because they contain DNA. The hair samples identified 185 unique bears in 1998 and 222 bears in 2000. Researchers used a statistical formula to arrive at the estimate of 240 bears.