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Grizzly Saviors

Through augmentation program, grizzlies continue slow comeback in Cabinet-Yaak Ecosystem

In the summer of 1993, biologists with the U.S. Fish and Wildlife Service captured a 2-year-old female grizzly bear in British Columbia, along the North Fork Flathead River about 10 miles from the U.S.-Canada border, northwest of Glacier National Park.

Before loading the 80-pound sub-adult onto a truck and spiriting her 150 miles away to the Cabinet Mountains in northwest Montana, the crew assigned her an official designation — Bear 286.

Biologist Wayne Kasworm affectionately called her Irene.

As the U.S. Fish and Wildlife Service grizzly bear recovery coordinator in Libby, Kasworm held lofty expectations for her future, and for the future of the dwindling grizzly bear population she was about to join.

The crew fitted Irene with a radio collar and an ear tag and, with a whisper and a prayer, turned her loose near Lost Girl Creek, on the west side of the Cabinet Mountains, a rugged expanse of snow-marbled peaks and lush forests sprawled out between the Kootenai and Clark Fork rivers.

Without knowing it, Irene was taking her first steps toward becoming an unlikely savior of the Cabinet-Yaak Ecosystem, one of six designated grizzly bear recovery zones in the Lower 48 where the federal government aims to protect or boost the threatened species.

Grizzly bears were listed as threatened under the U.S. Endangered Species Act in 1975, and isolated populations like the Cabinet-Yaak Ecosystem were in especially bad shape. Researchers were desperately trying to determine how to revitalize populations on the brink of collapse.

At the time of Irene’s release, Kasworm estimated that the grizzly bear population in the Cabinet Mountains had dropped to single digits, and was plummeting toward extinction.

The only way to save the remote Cabinet-Yaak population, Kasworm reasoned, was to supplement it with additional grizzly bears, a controversial and largely untested conservation strategy that he first proposed in 1987.

It wasn’t until 1990 that Kasworm began augmenting the sparse population with transplanted bears, and three years after that he introduced Irene to the region, the third grizzly transplant of a program now in its 26th year. In that time, Kasworm has introduced nearly 20 grizzlies.

Today, due in large part to Irene, he believes the conservation effort has finally started to take hold, and he uses the sow to illustrate the program’s bright spots, as well as its challenges.

Irene produced 10 first-generation offspring, and those cubs have gone on to produce 13 second-generation offspring.

“She was the matriarch of this population,” Kasworm said. “Through our genetic monitoring, we are hopeful that in the next couple of years we can document the third generation of offspring from Irene.”

In 2009, shortly after a trail camera captured a photograph of Irene with two yearlings, a hunter killed the bear in self-defense. And while the mortality was unfortunate, Kasworm said the yearlings survived, and Irene’s contributions remain significant for the burgeoning Cabinet-Yaak population.

The Cabinet-Yaak Ecosystem is a 2,600-square-mile region on the Montana-Idaho border abutting Canada, and by Kasworm’s population estimates it now holds roughly 50 grizzlies, with a projected rate of growth of 1.4 percent annually. Once on the verge of collapse, the population is nearly halfway to 100 — the threshold at which it would be deemed recovered, or no longer at risk.

Still, it pales in comparison to the robust grizzly populations of the much-larger Northern Continental Divide Ecosystem (NCDE) and the Greater Yellowstone Ecosystem, which each have more than 1,000 bears, and are growing at an annual rate of roughly 3 percent.

But the tenacity of the bears in the Cabinet-Yaak gives scientists hope that the population could function on its own in the years to come, while also serving as a point of connection for isolated grizzly populations throughout the Rockies.

The optimism is diminished by serious challenges cropping up on a landscape scored with roads and encroached upon by humans, with bear-human conflicts often leading to grizzly bear mortalities.

While some recovery zones, like the lands around Glacier and Yellowstone national parks, are protected, the Cabinet-Yaak is a multiple-use landscape, and it is also considerably smaller.

“We don’t have a large national park like Glacier or Yellowstone to anchor this recovery area, or a large wilderness area like the Bob Marshall to anchor this recovery area, so the population is much smaller,” Kasworm said. “Our recovery area is approximately a quarter of the size of the NCDE or the Yellowstone zones, so on the basis of the size alone we are not expecting near the population of bears.”

Every lost bear is a blow to the Cabinet-Yaak contingent, highlighting the need to curb human-caused mortalities, many of which are caused by hunters who mistake the threatened grizzly for a black bear, whose population numbers are dense in this corner of the state.

Since 1986, researchers have identified 176 individuals in the study area, with 147 bears captured or genotyped and 29 unmarked individuals observed. Sixty-four of the animals are known or suspected to have died, with human causes linked to 45 of the mortalities. Eighteen were believed to have died of natural causes.

“We are certainly hopeful that this population is going to rebound, and we are in the positive territory as far as the growth rate for the first time,” Kasworm said. “We’re moving more slowly than the other recovery zones, but our increase has been improving over the last several years, and as long as we can diminish the level of human-caused mortalities we expect to reach our recovery goal.”

Last year was an especially bad year for bear-human conflicts, and therefore a bad year for bear mortalities.

Kim Annis, a bear management specialist for Montana Fish, Wildlife and Parks in Libby, said on average she responds to about 150 conflict calls annually that require her to respond.

“Last year, I took 500 calls,” she said, noting that a poor year of food production drove bears toward unnatural food sources. “I usually capture eight bears in a season, and last year I captured 40 bears. And I probably could have captured three times that. It was a level that we had never seen in the past.”

Of those 40 bears, about a dozen were killed.

But her efforts to educate the public about securing attractants and protecting chicken coops with electric fencing are beginning to show promise, and with this summer’s better-than-average berry crop, Annis says she’s cautiously optimistic that there will be fewer conflicts.

“A lot of good things happened as a result of last year,” she said. “A lot of folks who I had spoken to in years past were finally interested in doing things like clearing fruit trees, electrifying fences and securing their livestock feed.”

Late last month, a 3-year-old male grizzly bear was captured in an area along the South Fork Flathead River and transplanted to the Cabinets, near the Spark Lake area of the Kootenai National Forest. Kasworm and his crew began introducing males to increase the potential for genetic diversity, but he’s still holding out hope that a female grizzly will be trapped in the next month or so as part of the Cabinet-Yaak augmentation program.

Because who knows? She could be the next Irene.

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