Grizzlies out and about after winter denning

Radio collar signals reveal that at least two male grizzly bears in the Cabinet-Yaak Ecosystem have left their dens but remain in higher elevations.

“I know this because a few males have a collar that sends me a signal with location data through the satellite phone system,” said Wayne Kasworm, a Libby-based biologist for the U.S. Fish and Wildlife Service.

He said he receives signals only a couple of times a week and “only when the bear and collar are in a location where a connection can be made.”

Estimates suggest there are about 50 to 60 grizzlies in the Cabinet-Yaak Ecosystem, with about half of the bears in the Cabinet Mountains and half in the Yaak.

Male bears typically emerge from dens before females.

“Males often emerge two to three weeks earlier than females and often a month earlier than females with newborn cubs,” Kasworm said.

Hibernating bears live off a layer of fat accumulated during the summer and fall months before hibernation. During hibernation they do not eat, drink, defecate or urinate.

Bears can lose 15 percent to 30 percent of their body weight during hibernation but do not lose bone mass, research shows. Heart rates can drop from 40 to 50 beats per minute during the summer to 8 to 19 beats per minute during hibernation.

Kasworm said recreationists in the region should be bear aware.

“People should carry bear spray and stay alert for bear sign when they are out in the woods,” he said.