The Bear Truth: Grizzlies' Snagged Hair Samples Reveal Dependence on Salmon

Poor salmon runs along British Columbia's central coast rain forest since 2003 have spurred scientists to gauge the fish's nutritional impact on grizzly bears















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Fisheries and Oceans Canada's Policy for Conservation of Wild Pacific Salmon  (as of yet unimplemented) adopts an ecosystem-based management plan for coastal salmon, and Darimont hopes that the results his study will help inform how much of the species should be allocated to natural ecosystems in order to safeguard the biodiversity of the "salmon forests."

"Well, I think all living beings have a right to use the resources and I have watched the bears, wolves in the spawning time use salmon," says Gary Housty, Heiltsuk hereditary chief. "So, you know, everybody is a user and when this is taken away from us by poor management it denies this great food that all users need."

Grizzly bears across the province of British Columbia have already been extirpated in 12 larger provincial parks and their numbers are severely reduced in seven more. Across the province, the population is declining in primarily due to habitat loss and habitat fragmentation. How much grizzlies are affected by salmon stocks remains unknown. The RCF study has identified 29 individual grizzlies in their study area, but Darimont has yet to crunch the numbers and project the population size.

Remote and vast study sites
To that end, the RCF is funding a long-term study that examines how intertwined grizzly bears are with their chief food source, salmon. The Raincoast researchers conduct noninvasive DNA, isotope and hormone analysis on grizzly bear hair samples collected from 72 sites, of which this one inlet is one. Roughly half the sites set up across this 5,000-square-kilometer remote study area are accessible by small helicopter. The rest by boat.

Since the study began a couple years ago, the researchers have expanded their study area by 2,000 square kilometers—at the same time that salmon numbers remain severely diminished.

The RCF's bear study follows the lead a similar study in the Koeye River watershed led by Coastwatch, the science arm of the Qqs Projects Society (pronounced kuks). Based in the tribal territory's coastal community of Bella Bella, Qqs is a Heiltsuk nongovernmental organization dedicated to promoting the nation's cultural and environmental values in local youth. The Coastwatch study, which reports to the Heiltsuk Integrated Resource Management Department, began as part of a drive to tally grizzly numbers in the vicinity of a Qqs youth science camp. William Housty is the director of Coastwatch and is leading the five-year study, which surveys grizzly bears in the Koeye watershed using hair-snagging stations. "We were able to paint a really good picture of the bears and their movement," says Housty, who is co-author on an upcoming research paper that outlines their results.

Stink sauce
I ask Housty why the bears matter so much, why they warrant such dedicated research. "Just by knowing that there's grizzlies in that territory tells us that that land is pristine—it has salmon, it has grass, it has spring habitats," he explains. "We know that our land is thriving because the bears are thriving."

One year Coastwatch collected hair from 65 individual grizzlies, all in just one river watershed. The scenery hugging the inlet head where the mother and her three cubs live is epic in its grandeur. We're at the water's edge of the Coast Mountain range, which is broader and higher than the Rockies in the U.S. Mountain peaks, softened by glacial retreat millennia ago and cloaked in inky green coastal western hemlock and red cedar forest, careen into the sea. Even from the water, the wintry and spicy smells of the forest meet our nostrils. A flock of goldeneyes take flight, trembling en masse as they rise. Beneath the hull of our boat, the kelp and eelgrass beds are a nursery for salmon fry, the start of a life cycle that ends with adult fish returning to the river system, feeding a whole forest with the nutrients locked in their reddened flesh.



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