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DNA study shows highest concentration of bears in Park
Posted: Wednesday, Feb 01, 2006 - 01:46:38 pm MST
By CHRIS PETERSON

Hungry Horse News As more and more data comes in from a huge grizzly bear DNA study, one thing is becoming increasingly clear: In Northwest Montana, Glacier National Park is a haven for grizzly bears. The United States Geographical Survey study gathered 33,739 bear hair samples across some 8 million acres of Montana real estate from the Canadian border south to the Blackfoot in the summer of 2004. Since then, USGS scientist Kate Kendall and her staff have been analyzing the data as it comes in from Wildlife Genetics International. So far, about half of the data samples have come in, Kendall said earlier this week.

The data has come up with some hard numbers and some trends, but the study still has a long way to go, cautions Kendall.

Even so, the numbers are fascinating. For example, one drainage in Glacier National Park alone sampled 23 individual grizzly bears. Glacier as a whole has by far the greatest concentration of bears.

All told, the study has affirmatively counted 331 individual bears across the 8 million acres. That doesn't mean there are only 331 bears in the ecosystem. It also doesn't mean you can simply double the number either and get a population, Kendall said. What it does mean is the study has positively identified 331 individual bears that entered the traps. A population estimate will come when the entire study is complete. There is still much work to be done as well. For example, scientists don't know if the bear population is going up or down - those figures come from population trend studies.

The traps aren't much, really. They work like this: A scented lure (usually something rotten, like fish juice) is placed on some sticks or other absorbent material. That lure is then fenced off with a carefully placed piece of barbed wire. Bears, being naturally curious, and always hungry, go into take a sniff.

As a result, most of them leave at least a little hair behind on the wire.

The hair can then be analyzed for a host of things - from the sex and lineage of the animal, to something far more simple - like the species.

For example, there was six times more black bear hair collected than grizzly bear. That doesn't mean there are six times more black bears, Kendall noted. But it does give researchers some idea of the density of the two species.

Kendall said the study didn't actually count the individual black bears - it doesn't have the funding to do so.

But the bottom line is this: Glacier is a good place for grizzlies. It has good food sources. Good habitat. And good security.

If you're a grizzly in Glacier, the odds of you being shot, hit by a car or running into some other sort of trouble that will get you killed are far lower.

That's not the same story in other parts of the ecosystem, where bears run into everything from poachers to pickup trucks.

“I don't think you can rule out the mortality factor,” Kendall said of bears outside the Park.

Kendall said the population study should wrap up in 2007. But this data could be analyzed for years. There's all kinds of neat science that can come from DNA analysis, such as relationships between grizzly and black bears.

There is a theory, Kendall notes, that black bear density may play a role in grizzly bear density.

But that's just a theory, she cautioned.

“That would be so cool, to look at the interaction,” of the two species, she said.

There are also other facets of DNA analysis. For example, you can determine the relationships between the bears themselves - who is related to who.

Are grizzlies kissing cousins?

You can also take DNA data and lay it over the top of habitat and plant data and determine, for example, what makes ideal grizzly bear habitat and what doesn't.

Meanwhile, Kendall, who has been studying grizzlies since 1977, when she started out with the interagency team in Yellowstone, is waiting for more results with anticipation.

“It's so exciting when another batch of results come in,” she said.

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