Evidence of griz cubs in Cabinets
A grizzly bear that was transplanted to the Cabinet Mountains last fall appears to have emerged from her den last month with no cubs. But there is hope for future cubs, based on the recently revealed genetic history of another bear that was moved to the Cabinets in 1993.
The main purpose of "augmenting" the imperiled Cabinet grizzly population is not to add a single bear, but to import a female bear to reproduce. Four females were transplanted from British Columbia to the Cabinets between 1990 and 1994, but no one knew for sure whether any managed to have cubs - until just recently.
DNA analysis of bear hair samples collected during the past three years has confirmed that one of the females transplanted in 1992 not only had cubs, but also that her cubs reproduced, said Wayne Kasworm, a U.S. Fish and Wildlife Service biologist who monitors the Cabinet grizzly population.
"She has produced at least five other bears, and three of them are her children and two of them are her grandchildren," Kasworm said. "We got the confirmation in the spring."
It's a significant revelation, according to Kasworm and Chris Servheen, the Fish and Wildlife Service's grizzly bear recovery coordinator.
It basically provides confirmation that the augmentation program was successful, Kasworm said.
"We augment bears to get them to reproduce, and in this case we were able to document that happening," Servheen said. "This was great news that she reproduced and even better news that her offspring reproduced. It confirms that augmentation works."
The matriarch grizzly is now about 15 years old, and she's thought to be alive because one of her hair samples was picked up at a scent-baited site last summer.
Speculation about the fates of the other three bears that were moved to the Cabinets in the early 1990s is not as optimistic. One died soon after being moved in 1992. Another immediately left the Cabinets, was recaptured and returned and hasn't been seen since. And the third hasn't been seen since its release.
"Those other two are possibly still there," Kasworm said.
A burly female bear that was captured in September in the North Fork Flathead drainage became the first grizzly to be transplanted to the Cabinets in 11 years. She was released in the west Cabinets, above Spar Lake, in September and by winter she had denned up just a few miles away.
Kasworm and other biologists who were involved with the transplant speculated she might be pregnant. But that wouldn't be known until she emerged from her den this spring.
Kasworm has not spotted the radio-collared bear on recent telemetry flights, but judging from the distance of her movements, he does not think she has cubs with her.
"I really would not expect that she would be dragging cubs over the distance she's been covering," said Kasworm, who has plotted the bear moving a distance of about 17 miles south to north.
But mating season is under way, and Servheen thinks there's a good chance a male will find her.
The Fish and Wildlife Service officially estimates that there are only as many as 15 grizzly bears in the Cabinet Mountains, and another 20 to 30 bears in the Yaak, the northern region of the grizzly bear recovery zone.
The overall population status is tenuous, with three known deaths just last year.
Reporter Jim Mann may be reached at 758-4407 or by e-mail at jmann@dailyinterlake.com.