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Northwest grizzly count tops 545
Posted on Dec. 26
By the Associated Press
GREAT FALLS - More than 500 "unique individual grizzlies" roam the northwestern Montana backcountry from the Canadian border to Lincoln, with Glacier National Park boasting the largest number, according to DNA studies conducted by the U.S. Geological Survey.
In 2004, the bears left behind identifying hairs at tree rubs and on barbed wire, which were collected by researchers. The strands were DNA calling cards for geneticists, who recently determined that 545 different grizzlies visited the collection sites.
The work is part of what is believed to be the largest DNA-based wildlife population survey conducted in the world.
Not every bear in the ecosystem visited the hair-collection locations, so the 545 figure is a minimum count, not a total population estimate. Researchers in 2007 will continue to work on establishing a total population projection, factoring in the uncounted bears. A figure could be publicly available in late 2007 or in 2008.
Nonetheless, the minimum count of 545 is the first solid number bear managers have had for the Northern Continental Divide Ecosystem, one of the lower 48's few remaining grizzly strongholds. The hard data will be used in the management and recovery of the threatened population, they say.
"That probably was a lot more bears than anybody thought were out there," Chris Servheen, the nation's grizzly bear recovery coordinator, told the Great Falls Tribune.
Over 12 weeks in 2004, 34,000 hair samples were collected across 7.8 million acres stretching from the Canadian border to state Highway 200 on the Northern Continental Divide Ecosystem's southern border and from U.S. Highway 89 on the eastern edge to U.S. Highway 93 in the west.
The hairs were caught on barbed wire at 2,500 "hair corrals" put up as part of the study. Bears investigated because of scent placed at the corrals.
More than 5,000 natural bear rub trees, where bears leave their scent to let other bears know they're around, were checked as well.
The DNA project is led by the Geological Survey and supported by other federal, state and tribal agencies. Recent advances in genetic technology are being used to estimate population size.
The DNA fingerprints left on the barbed wire and trees allowed researchers to pinpoint not only the 545 individual bears, but gender and species (black bear or grizzly) as well.
Information on distribution and the range of bears also was gleaned.
Prior to the study, "We haven't had any way to measure the effectiveness of all of the recovery measures that have been taken," said U.S.G.S researcher Kate Kendall.
Glacier National Park makes up just an eighth of the Northern Continental Divide Ecosystem but it had almost 50 percent of the unique bears, the study found.
Kendall attributed the higher number to Glacier's climate, habitat and its protective national park designation.
Posted on Dec. 26
By the Associated Press
GREAT FALLS - More than 500 "unique individual grizzlies" roam the northwestern Montana backcountry from the Canadian border to Lincoln, with Glacier National Park boasting the largest number, according to DNA studies conducted by the U.S. Geological Survey.
In 2004, the bears left behind identifying hairs at tree rubs and on barbed wire, which were collected by researchers. The strands were DNA calling cards for geneticists, who recently determined that 545 different grizzlies visited the collection sites.
The work is part of what is believed to be the largest DNA-based wildlife population survey conducted in the world.
Not every bear in the ecosystem visited the hair-collection locations, so the 545 figure is a minimum count, not a total population estimate. Researchers in 2007 will continue to work on establishing a total population projection, factoring in the uncounted bears. A figure could be publicly available in late 2007 or in 2008.
Nonetheless, the minimum count of 545 is the first solid number bear managers have had for the Northern Continental Divide Ecosystem, one of the lower 48's few remaining grizzly strongholds. The hard data will be used in the management and recovery of the threatened population, they say.
"That probably was a lot more bears than anybody thought were out there," Chris Servheen, the nation's grizzly bear recovery coordinator, told the Great Falls Tribune.
Over 12 weeks in 2004, 34,000 hair samples were collected across 7.8 million acres stretching from the Canadian border to state Highway 200 on the Northern Continental Divide Ecosystem's southern border and from U.S. Highway 89 on the eastern edge to U.S. Highway 93 in the west.
The hairs were caught on barbed wire at 2,500 "hair corrals" put up as part of the study. Bears investigated because of scent placed at the corrals.
More than 5,000 natural bear rub trees, where bears leave their scent to let other bears know they're around, were checked as well.
The DNA project is led by the Geological Survey and supported by other federal, state and tribal agencies. Recent advances in genetic technology are being used to estimate population size.
The DNA fingerprints left on the barbed wire and trees allowed researchers to pinpoint not only the 545 individual bears, but gender and species (black bear or grizzly) as well.
Information on distribution and the range of bears also was gleaned.
Prior to the study, "We haven't had any way to measure the effectiveness of all of the recovery measures that have been taken," said U.S.G.S researcher Kate Kendall.
Glacier National Park makes up just an eighth of the Northern Continental Divide Ecosystem but it had almost 50 percent of the unique bears, the study found.
Kendall attributed the higher number to Glacier's climate, habitat and its protective national park designation.