People pose threat to Cabinets bears

There’s good news and bad news for the remote population of grizzly bears in the Cabinet-Yaak Mountains of northwest Montana.

Although their numbers are climbing out of the “negative territory” for the first time in decades, wildlife officials say human-caused mortalities continue to plague the tenuous population, which is estimated to number around 50, with a projected growth of 1.4 percent annually.

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

Wayne Kasworm, the U.S. Fish and Wildlife Service recovery coordinator in Libby, said augmenting the sparse population with transplanted bears – an effort begun in 1990 – has finally started to take hold.

But every lost bear is a blow to the Cabinet-Yaak contingent, and the discovery of another dead grizzly in the Yaak in late May highlights 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.

Kasworm said the trend of grizzly deaths has fallen into three main categories: malicious kills, cases of mistaken identity and instances of legitimate self-defense.

“Historically, we have had a lot of human-caused mortality that pushed the population into decline,” Kasworm said. “In recent years though things have turned around and trend monitoring now indicates that we are growing.

“But, when we lose a bear or two out of a population of 50 bears, it’s a much bigger deal than when we lose a bear or two out of a population of 1,000 bears over in the Northern Continental Divide Ecosystem.”

With four times the territory of the Cabinet-Yaak, the NCDE extends from the southern tip of the Rattlesnake Wilderness north of Missoula north to Glacier National Park.

More isolated populations of grizzly bears, which were listed as threatened under the U.S. Endangered Species Act in 1975, exist in more isolated habitats like the Cabinet-Yaak, and require transplants from more bear-dense areas to maintain genetic diversity and make up for the mortalities, both natural and unnatural.

“Basically, we didn’t know how many bears we had but estimated 15 or fewer, and we felt unless we did something we were running a high risk of losing the population,” Kasworm said.

Beginning in 1990, researchers with the Fish and Wildlife Service added four grizzlies to the Cabinet Mountain population. However, they were young bears and, since grizzlies don’t begin to reproduce until they are 6 or 7 years of age, it has been a long process.

After 15 years, there was an indication that the population was increasing and that the augmentation program was a success, Kasworm said. The biologists began moving male grizzlies into the area in addition to females to increase the genetic diversity.

Continuing those efforts, state and federal biologists plan to bring a new male and female grizzly to the population this summer to join two females successfully introduced last year.

Those two siblings were expected to stay together in the Spar Lake area of the Scotchman Peaks, where they were released. But Kasworm said they split up, with one moving to the main Cabinet Mountains and the other going south around Ross Creek.

Both females successfully denned and re-emerged this April.

The main Cabinet Mountains have received 17 transplanted bears since 1990. Four of those have left the area (typically heading back to the NCDE), while four more have died.

The Cabinet-Yaak could also benefit from travel linkages connecting bears from the NCDE to the Cabinet-Yaak as the former reaches carrying capacity. However, as the human-wildlife interface continues to overlap those corridors are increasingly fractured by heavily populated urban areas.

Even within the Cabinet-Yaak, Kasworm says there is scant internal linkage, or instances of grizzlies migrating between the Cabinets and the Yaak.

The region received a boost in habitat connectivity in 2012 when a conservation project added 28,000 acres of prime wildlife habitat to the lower Kootenai River Valley. The land was sold by Stimson Lumber Co. as an easement to the Trust for Public Land and Montana Fish, Wildlife and Parks, which manages the easement. The project cost $12.8 million and means the land cannot be sold privately for subdivisions.

The project area is near Troy and tracks along the Cabinet Mountains and the Yaak and Kootenai rivers, stretching from the south end of Bull Lake, north through the Lake Creek drainage to Troy, and then northwest along both sides of the Kootenai River to the Idaho border.

“That was a pretty major deal,” Kasworm said. “We’re talking about a major conservation easement on some lands that will help us protect our internal linkages.”

Northwest Montana also has some of the state’s greatest concentrations of black bears, which draws hunters from both in and out of the region. Black bear hunters are required to take an identification course to recognize the differences between the two species, but mistakes still happen.

Kasworm favors more education, suggesting that black bear hunters should be required to take refresher courses rather than a single, lifetime course as currently mandated.