Web exclusive: Grizzlies continue to face challenges

Montanans interested in the well being of grizzly bears have had good and bad news recently.

After 26 years, the Yellowstone grizzly bear population was declared recovered. The bears were removed from the federal list of endangered and threatened wildlife species in April 2007, though grizzlies in the Yellowstone Ecosystem still face challenges.

"Human caused grizzly mortalities continue to be scrutinized, especially for female grizzly bears that are critical to the survival of the bears in the Yellowstone Ecosystem," said Chris Smith, Montana Fish, Wildlife & Parks deputy director and a long-time member of the Interagency Grizzly Bear Committee.

"A serious issue for grizzly bears is the unprecedented attack of mountain pine beetles on whitebark pines," said Smith.

Whitebark pine seeds are a staple in grizzly bears' diets in the Greater Yellowstone and Northern Continental Divide Ecosystems.

Smith said some bear biologists are concerned that the loss of the nutritional whitebark pine seeds could in turn reduce the grizzly bears' reproductive success.

"Providing areas where grizzlies can expand their range and find new foods will be an important part of helping the bears cope with the loss of whitebark pine trees," Smith said.

In another part of the state, the Northern Continental Divide Grizzly Bear Project concluded there were an estimated 765 grizzly bears in the Northern Divide ecosystem in 2004—well above what was expected. This project involved two years of fieldwork by more than 200 researchers and crew and three years of analysis of more than 34,000 bear DNA samples.

Researchers genetically analyzed the bear hair samples, identifying 563 individual grizzly bears, then used statistical models to estimate the total number of bears.

 The Northern Continental Divide grizzly population is one of five grizzly bear recovery zones located in portions of Wyoming, Montana, Idaho and Washington.  Grizzly bears also occur north of the border in Canada and in Alaska.

In the Cabinet-Yaak Ecosystem, in northwestern Montana, the grizzly population is the smallest in the state, about 40 bears. FWP's work with the U.S. Fish and Wildlife Service to boost this population by transplanting a limited number of young female bears has met with some success and a recent set back. The two female bears released into this ecosystem in 2008 died about two months after their release—one was struck by a train and the other shot and killed at a residence outside of Noxon The work to augment the grizzly population in the Cabinet Yaak Ecosystem will continue.

The ultimate good news would be that grizzly bears are finding ways to interbreed between some recovery zones. IGBC scientists and the U.S. Geological Survey recommended genetic testing to discover whether grizzly bears in the Yellowstone region have interbred with grizzlies from elsewhere.

"Interbreeding between grizzly bear recovery areas is important insurance for the future because it will maintain the genetic diversity they need to withstand diseases and other pressures on them," said Smith.

In the meantime, Montana's grizzly bears are experiencing significant reductions and changes in key habitat, fragmentation of travel corridors from one ecosystem to other, changes in foods available to them and increased contact with humans.

"The successful management of grizzly bear populations includes a commitment to address the challenges posed by the many environmental changes the bears face," Smith said.

(Diane Tipton is the statewide information officer for Montana Fish, Wildlife and Parks).