Study: Highest concentrations in Glacier Park

Just more than half the results are in, but they are revealing a remarkable picture of the Northern Continental Divide grizzly bear population.

The results are being gleaned from genetic analyses of 33,739 hair samples that were collected from rub trees and scent-baited snare sites that were spread over 8 million acres in summer 2004.

About 57 percent of them have been analyzed by Wildlife Genetics International in Nelson, British Columbia, said Kate Kendall, a U.S. Geological Survey scientist who is leading the Northern Divide Grizzly Bear Project, a massive effort to develop a snapshot grizzly bear population estimate.

"There's only so much you can do with only half your samples in," Kendall told a group of about 60 people who attended a Glacier National Park Associates presentation in Kalispell this week.

But some things about the population have become apparent as the genetic analyses progress.

"It's pretty obvious that Glacier National Park has a whole lot more bears than anywhere else," Kendall said, displaying a map showing a considerably denser concentration of grizzly hair samples being collected in and around the park. The density of dots, representing bears, progressively fades in the Bob Marshall Wilderness Complex and further south into the Rattlesnake Wilderness.

"I don't think it's a surprise to anybody, but there's a much lower density in the southern part of the study area," she said.

So far, the hair samples indicate that six black bears exist for every grizzly bear within the ecosystem.

The study has yielded some insights into grizzly bear behavior. About 66 percent of the bears that were attracted to the snare sites - basically a single strand of barbed wire surrounding a scent-baited pile of logs and sticks - were female.

Meanwhile, males accounted for 78 percent of the hair samples that were collected from trailside bear rubs - trees, power poles and signs.

"Males tend to dominate these rub trees," Kendall said.

The analyses also have shown just how much some bears, particularly males, can move.

A bear dubbed "Stanley" because his hair was first picked up in the Swan Valley's Stanley Creek drainage left more hair samples 35 miles away within a two-week period.

Another bear, "Buck," left hair samples in the Wounded Buck area west of Hungry Horse Reservoir. Within two weeks, he had left more hair 25 miles away, across the reservoir, at another hair snare.

"I don't know if he likes to swim or if he went around" the reservoir, Kendall said.

Remote video cameras positioned at hair snare sites also shed light on bear behavior.

In most instances, the cameras captured the largest bears cautiously approaching the barbed wire and gingerly stepping on it to get to the scent-baited wood pile.

"I'm actually surprised that we got as much hair as we did with so many bears stepping on the wire like they did," she said.

A remote camera captured remarkable footage of a wolverine investigating one of the scent-baited sites. At another site, a curious grizzly bear was attracted to the tree-mounted camera. The footage shows the bear battering and slobbering all over the camera.

"Oddly enough, the camera wasn't damaged, because the bear did get it off the tree," Kendall said.

So far, the genetic analyses have identified 331 individual grizzly bears throughout the ecosystem.

"But a population estimate is not based on a minimum count," cautioned Kendall. That's because hair samples are collected from a fraction of the bears in the ecosystem.

When the genetic analyses are complete, Kendall will begin the long process of crunching numbers to produce a "mark-recapture" statistical model that will yield the first scientifically reliable population estimate for the ecosystem. She does not venture any guesses about what that estimate may be.

"We originally anticipated it would take about 18 months" to complete the genetic analyses, Kendall said. "And we're about on track with that so far."

For the past few years, Kendall has been finalizing data from a similar population study that was carried over 2 million acres in and around Glacier National Park from 1998 through 2000. The preliminary population estimate from that study: about 300 grizzly bears.

But that number is bound to change because of more-detailed analyses of hair samples that have filled in "gaps" and improved the statistical confidence of the study. Hair samples originally were analyzed at the University of Idaho, with smaller samples excluded.

The laboratory in Nelson has reviewed those samples that were excluded, and as a result 46 more bears were identified.

"It was very exciting," Kendall said. "I was just delighted. We put a lot of work into collecting those samples, and we wanted to get as much information as we could from them."

Kendall expects to produce a final population estimate from that study by the end of February. But she said those results will not be released until the study is peer reviewed and published in a research journal, and that could take more than a year.

Reporter Jim Mann may be reached at 758-4407 or by e-mail at jmann@dailyinterlake.com.