Female grizzlies are trackedto study population trends

It can be dicey work for those who do it, but keeping 25 female grizzly bears fitted with radio collars along the Northern Continental Divide is considered a priority for determining the status of Montana's largest grizzly population.

It is also considered a prerequisite for recovering and delisting the population that ranges more than 8 million acres from the Canadian border south to the Ovando area, said Rick Mace, a research biologist with Montana Fish, Wildlife and Parks.

Starting last summer, Mace got the collaring operation under way, capturing and fitting seven bears. The effort continued early this summer, with a total of 23 bears being fitted.

It's been a challenging endeavor for Mace and a handful of assistants, most of them bear management specialists who cover different parts of the sprawling grizzly bear recovery area. But it has been a relatively low-profile effort compared with the huge grizzly bear population study carried out last summer.

That project involved dozens of field workers who collected 33,000 hair samples from scent-baited sites, surrounded by hair-snagging barbed wire, at locations across the recovery area. The hair samples, which are being analyzed at a genetics laboratory in British Columbia, will identify individual grizzly bears. A "mark-recapture" statistical analysis eventually will generate an unprecedented population estimate.

"There are two pieces to the pie," Mace explained. The first piece is the population estimate, and the second is the ongoing effort to monitor female grizzly bears to determine whether the population is shrinking or growing.

"The math gets heavy," Mace said, explaining the population trend study. "But in the simplest sense, it's just the birth rate and the death rate. If mortality is greater than the birth rate, the population is going down."

But judging population trends requires an ongoing effort to be statistically valid. With 25 collared bears, Mace said, it will take five years to produce a trend estimate with a degree of confidence.

"We need a minimum of 25 bears on the air at any time," he said, noting that some people think even more bears should be collared to improve the statistical confidence of the trend monitoring effort.

That would be nice, Mace said, but Montana Fish, Wildlife and Parks is pursuing the effort within its means, making use of existing staff to collar the bears and keep track of them.

Bear wrangling isn't much of a problem for bear managers in front-country areas where they can approach traps or troublesome bears with a pickup. It's a totally different story in the backcountry, where Mace and his crew set snares far from the safety of a pickup.

"It can get pretty sketchy" approaching a snare in the backcountry, Mace said. A cub could be caught in the snare with a protective mother nearby, or during mating season, a female bear could be in the snare with an agitated male nearby.

Most of this summer's bears were caught without incident, in varying types of remote, backcountry locations. There's been no trouble, Mace said, because the people he's working with are highly experienced and they "know what they're doing." Among those assisting Mace are bear management specialists Tim Manley, Erik Wenum, Jamie Jonkel, Mike Madel and Tim Carney.

One of the more challenging aspects of collaring bears in the backcountry is the time investment and the logistical planning required. If one bear is needed in the Spotted Bear area, catching a female bear may take a week or more.

"It all varies. Sometimes it's real quick and sometimes it's real slow," Mace said. "There are times when you don't catch anything at all."

At times, a trapping crew may have the luxury of a backcountry cabin, but at other times, tent living is as good as it gets.

Most of the bears that have been collared have been in more accessible backcountry locations. That will change next summer, when the focus will be on collaring bears in the most remote interior of the Bob Marshall Wilderness Complex.

"The challenge will be next year, when everything's on horses in the Bob Marshall," Mace said.

So far, most of the bears have been fitted with radio collars that must be tracked from aircraft rigged with radio telemetry equipment. But Mace has put out a few collars with global positioning satellite transmitters.

Although they are more costly, the GPS collars quickly pay for themselves because they can be remotely monitored, with no aircraft rental fees.

From his office in Kalispell, Mace can tap into a computer database that downloads location feeds from the bears that are wearing the GPS collars. Within minutes, he can see a series of recent locations for bear No. 49873, still moving about in her home range near Granite Park Chalet in Glacier National Park.

At the right times of year, Mace can quickly catch up with her in an airplane to determine whether she has cubs. If her collar stops moving, he can confirm whether she has died.

The state's monitoring effort is tied in with similar research that is being conducted in the Canadian provinces of British Columbia and Alberta.

Mace is cooperating with Canadian researchers in keeping tabs on two collared grizzly bears that regularly roam across the border into Glacier National Park, near Waterton Lake and Kintla Lake.

In time, the monitoring effort should shed light on the nature of grizzlies in the Northern Rockies.

"It will be real interesting to see how tied Glacier bears are to the lower part of the recovery area," Mace said.

"Also, we may see varying reproduction rates," he said. Bears on the east front may have lower reproductive rates than Glacier bears, or vice versa.

The study also may reveal "mortality sinks" - areas where bears have a higher tendency to die.

"We may very well find either natural or man-caused mortalities in areas where we didn't think there were mortalities," he said.

The study also is expected to reveal more information about the relationship between bears and roads. It should show whether the collared females avoid roads, if they tend to die near roads.

The trend study will ultimately provide bear managers with information that could lead to removing Northern Continental Divide grizzly bears from protection under the Endangered Species Act.

The process for delisting grizzly bears in the greater Yellowstone area is under way, largely because a similar popular trend study has been carried out for years in that ecosystem.

"There is no question that this species will not be delisted unless there is long-term monitoring," Mace said.

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