Grizzly bears and aboriginal tribes in Canada have lived with each other for thousands of years. But one First Nation tribe, the Heiltsuk of British Columbia, was surprised to discover just how many bears a new study turned up in its backyard.

The Heiltsuk live near the Koeye watershed—69 square miles (179 square kilometers) of temperate forest on the central British Columbia coast—and they thought about a dozen grizzlies lived in their midst. But a scientific study, led by the Heiltsuk and published in late June in the journal Ecology and Society, found that the Koeye actually hosts at least 57. That's not your average bear density.

By comparison, Yellowstone National Park is about 3,472 square miles (8,992 square kilometers) and hosts only about 150 grizzly bears.

"It was a bit of a shock to me," says William Housty, lead author of the study and director of Coastwatch, the research arm of the Heiltsuk First Nation.

Not that it's surprising that grizzly bears are drawn to the area. The river that drains Koeye Lake has pink, chum, sockeye, and coho salmon, all tasty prey for bears. But neither Housty nor his colleagues expected to find nearly 60 grizzlies. (See: "Grizzly Bears Moving Into Canada's Polar Bear Capital.")

View Images NG STAFF, JAMIE HAWK. SOURCES: IUCN; HEILTSUK TRIBAL COUNCIL

Living With Bears

For the study, the team collected hair samples from Koeye grizzlies by using wire snares baited with enticing scents, though no food. When a grizzly came to investigate and rubbed against the wire, it left behind a tuft of hair.

The study authors collected the hair samples between 2006 and 2009, and sequenced the DNA to get a handle on how many individual bears they had and to determine their gender. (Watch a video of a grizzly mom teaching her cubs.)

They were also able to track some of those bears as they wandered out of the Koeye watershed. Some of the grizzlies ranged for hundreds of miles, crossing into the traditional territory of other First Nations.

Being able to obtain scientific data to back up Heiltsuk traditional knowledge about grizzly bears has been important, says Housty. The Heiltsuk have been trying to get more say in the management of their resources, including grizzly bears and salmon, and they've realized that science is one way to do that.

"Even though we're on the ground living with [grizzly bears and salmon]," explains Housty, "sometimes the final decision on their management comes from the government."

He adds, "We wanted to show that we're committed to dovetailing traditional knowledge and science to move toward managing our resources ourselves." (Read more about the First Nations in National Geographic's News Watch.)

What's even more exciting about this study, says study co-author Chris Filardi, an ecologist with the American Museum of Natural History in New York City, is that scientists and the Heiltsuk were able to carry out their survey in accordance with the laws of the Heiltsuk First Nation. One of the most important of those mandates was to not handle the bears or subject them to invasive procedures.

"You Can't Ignore the People"

The scientific data have also been a boon to the Heiltsuk resource management department, Filardi says. "If they see their policies don't make sense, it changes right away."

And advances in extracting and analyzing DNA from animals are extremely important to conservation efforts.They help researchers figure out, for instance, how many animals are in a population, says Michael Sawaya, a carnivore ecologist with Sinopah Wildlife Research Associates in Missoula, Montana.

He also says that noninvasive methods like the hair sampling in the new study allow scientific studies to better align with cultural beliefs and practices of the local community.

"Oftentimes wildlife research focuses on the wildlife, which it should," says Sawaya, who was not involved in the new research. "But you can't ignore the people, especially in areas that are under threats or [are] on indigenous lands."