Grizzly bears number 45
Cabinet-Yaak preliminary count may include up to 55 bears
The preliminary study results for the grizzly bear population in the Cabinet-Yaak Ecosystem was as eagerly anticipated — perhaps even more so — as any federal study in the Northwest.
The three-year study found the system has 45 grizzlies or about half that of what the U.S. Fish & Wildlife Service has determined as full recovery. The agency has established 100 bears as its benchmark for full recovery.
U.S. Fish & Wildlife Grizzly Bear Biologist Wayne Kasworm said he will continue concentrating on reducing bear mortality, improving the augmentation program and the examining the linkage of the Cabinet-Yaak Ecosystem grizzlies to others in the Northern Continental Divide Ecosystem
“The recovery seems to be going well. Whether that number is 45, 49 or even 55 on the high end. However you split that number. We’re only halfway there,” Kasworm said.
Last Monday, Kate Kendall, with the U.S. Geological Survey’s Northern Rocky Mountain Science Center, apprised Lincoln County commissioners and other officials of the preliminary results of the study.
With the aid of a PowerPoint presentation, Kendall explained the intricacies of the report that utilized hair snaring, genetic analysis and mark-recapture modeling of collared bears. The study area included 2.4 million acres of the Cabinet-Yaak Ecosystem, 1.7 million acres of which were in the Grizzly Bear Recovery Zone, eventually determining that at least 42 and as many as 55 bears share part of the year in the ecosystem.
Study setup began in 2011 with bear rub identification zones that included a crew of five, eventually establishing 1,017 bear rubs in a distance of 3,542 miles.
During the 2012 field season, the crew was expanded to include 72 crew members working from eight base camps establishing hair corrals that included 100-foot barbed-wire areas baited with a scented lure. A total of 395 cells were established in 5-by-5 kilometer grids. Each corral was monitored for five, 14-day sessions. The concoctions of bear lure were just too attractive for grizzlies to avoid, consisting of 75 55-gallon drums with a mixture of 1,300 gallons of fish, 2,400 gallons of blood of which four gallons were poured as attractant in each cell. The fish blood was aged one year, just to make it especially enticing for grizzlies. Also, there were secondary scents of anise, skunk and cherry.
The orange arrow points to the Yaak, connected to Griz habitat in Alberta but cutoff from both more southern and western Griz habitat in the USA
In all, there were 18,761 hair samples recognized, of which 11,280 or about 60 percent were sent for analyzing, Kendall said. She explained that many instances there were two or more tuffs of hair. In that case, the best tuff was harvested for analyzing to minimize the cost while maximizing the hair samples, she said.
Samples also were gathered from trees, power poles sign posts, but at these sites there were no attractants. In all, 1,386 rub sites were analyzed during eight 14-day intervals.
In all, there were 28 grizzlies detected at 1,975 hair trap visits from 10,405 hair samples, of which there were 17 males.
From the bear rub samplings, which consisted of 8,256, there also were 28 grizzlies detected, 15 of which were males.
Collectively, from the corrals and rubs, scientists detected 38 grizzlies, of which 21 were males. Kendall said of the 38 grizzlies detected at both rub and hair snagging, 26 percent were sampled in corral only while 26 percent were rub only. However, 47 percent were detected at both sampling areas.
Kendall said in addition to the 38 baseline grizzlies, there were four bears that were detected or known from other methods, such as two full-time collared bears. All of these bears were detected during the June 7 to Sept. 26 study period. Also, there were two bears detected in first-pass rub collections, but it is unknown whether those samples were from 2011 or 2012. Kendall said there also was another collared bear transmitting until mid-May. Biologisits are unsure whether the collared bear was alive, but it was counted for the study. Of those 45 bears, there is nearly an equal mix of males (23) to females (22).
For the sake of the study and offering numbers beyond the minimal tally because not all grizzlies were sampled, Kendall said there are two ways to determine population size, one is the average population and the second, the super population, which reflects grizzlies traversing the Cabinet-Yaak Ecosystem boundaries. Both numbers reflect a nearly equal population of males to females.
Separating the region-specific tallies — Kendall cautioned this is just a preliminary report — that the Cabinet and the Yaak grizzlies are nearly an even split with one more grizzly in both the average population and super population in the Yaak boundaries.
Kendall also provide some insight into the saturation numbers of grizzlies in the ecosystem. For example in the 395 cells, grizzlies were detected in 103 cells or in 26 percent of the possible cells. Interestingly, Kendall said of the same 395 cells, black bears were recognized in 387 cells or in about 98 percent.
While the numbers still are not definitive, Presiding Commissioner Tony Berget said the study provides a starting point.
“This brings us to the table,” Berget said. “For years, the grizzly bear has been the hammer, something to prevent logging, mining, huckleberry picking or even hunting. It’s all been impacted by the grizzly. This is a starting point. They say they want 100 grizzly bears in the Cabinets. How do we know its even capable of supporting that many bears? This is something we can start with.”
Eric Klepfer, of Klepfer Mining, has been working to permit the Montanore Mine.
About three years ago, Montanore conducted a grizzly bear scat study for a cost of $250,000 that indicated there were about 40 bears in the ecosystem.
“We’ve been something at arms length with this,” Klepfer said. “But the study we did showed more than 40 bears in that system, which I guess is a good validation of what we’ve done.”
Concern for grizzlies — and the proposed mine’s impact on hydrology and bull trout — is one of the impacts Mines Management must address in its studies as it seeks permitting.
Kootenai National Forest Supervisor Paul Bradford, who also attended Kendall’s presentation of preliminary numbers, said the research reflects several years of effort.
“It’s a good foundation,” Bradford said. “We’ve been building on this for several years. It’s something to build on.”
Kendall will present her findings this week in Missoula to the Interagency Grizzly Bear Committee.
In 1975 grizzly bears were listed as threatened under the Endangered Species Act.
The Cabinet-Yaak Ecosystem in Northwest Montana and northeast Idaho is one of six recovery zones defined in the Grizzly Bear Recovery Plan (U.S. Fish and Wildlife Service 1993). The ecosystem is the fourth largest in area and contiguous to a small Canadian population. Estimates place the total number of grizzlies that remain south of the Canadian border at fewer than 1,100.
For more information about grizzly bear recovery, visit the U.S. F&WS Grizzly Bear Recovery Office webpage.
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