At secluded sites across Alberta this summer, grizzly bears — enticed by the perfume of fresh berries, molasses, rancid fish or cow’s blood — will wander into corrals hemmed with barbed wire.
Known as hair-snag sites, the scent lures are part of a new, long-term study monitoring the health of grizzly bears in the province.
The traps are designed to capture hair from each passing bear, helping conservationists better track Alberta’s fragile populations of the giant, solitary predators.
At each site, researchers build a mound of sticks and moss and douse it with something stinky. When curious bears come to investigate, they leave behind tufts from their summer coats.
“When they cross the barbed wire, they leave a little tuft of hair. That’s what we’re looking to collect,” said Darío Fernández-Bellon, a wildlife biologist and project lead with the Grizzly Bear Monitoring Project.
“They often enjoy themselves and have a little rub or a roll.”
“Everybody wins. We get our hair and the bears get a little bit of enjoyment out of it as well.”
The study builds on more than two decades of previous research by the fRI Research Grizzly Bear Program, which has surveyed grizzly populations in Alberta for more than two decades.
The government of Alberta maintains that its efforts to restore grizzlies to the landscape are working but researchers involved in the study caution that more consistent monitoring is needed to ensure the bears can thrive.
Tracing the family tree
Hair captured in the snag sites helps researchers assess the survival, reproduction and health of the species.
Each sample undergoes a DNA and hormone analysis, allowing researchers to create genetic profiles of each bear.
The profiles provide insight into the health of individual bears and have contributed to the creation of a genetic database of nearly 31,000 hair samples, tracing decades of bear lineages.
Fernández-Bellon likens the project to popular ancestry sites, where a single DNA swab can help chart multiple generations of a human family tree.
The data can reveal if a bear is male or female, a cub or an adult. Researchers can learn if a sow is pregnant, and how many cubs a male bear, known as a boar, has sired.
Fernández-Bellon said hair sampling provides researchers a wealth of information, without bothering the bears one bit.
“The official term for what I do is non-invasive sampling, but I see it more as landscaping for bears or doing bear entertainment,” he said with a laugh.
“They obviously love the smell. They’re kind of like dogs in that way. If there’s something smelly around, they’re going to roll in it.”
We’re trying to move beyond counting bears.– Dario Fernández-Bellon
The researchers have been working to perfect their hair-snag methods since 2004, gathering hair samples from a vast research area along the eastern slopes of the Rockies, stretching from Grande Cache to the Castle region.
The study initially focused on creating detailed inventories of each population in each of Alberta’s bear management zones.
Researchers now are hoping to develop a less labour-intensive approach that will provide a demographic snapshot of Alberta’s grizzly bears rather than a detailed census, Fernández-Bellon said.
“We’re trying to move beyond counting bears,” he said.
Grizzlies have been classified as an at-risk species in Alberta since 2010.
Understanding the grizzly population is critical to conservation efforts, Fernández-Bellon said.
He said he is hopeful the project will encourage provincial investment in grizzly research and empower community groups to participate in the work, which is currently industry-funded.
Once abundant across the province, the number of grizzlies dwindled for decades, reaching a low in 2010 when the total population was estimated at 700 bears. In a statement to CBC, the province said the number of grizzlies has since increased.
“We can proudly say Alberta’s grizzly bear recovery plan is working successfully over the last few years,” said Ryan Fournier, an Alberta Environment spokesperson. “Today, we estimate there are 1,000-1,100, if not more.”
The province said it is designing a new long-term monitoring program for grizzlies and that fRI Research will be consulted as that new strategy is developed.
Government officials did not provide a timeline for when the new monitoring strategy is to be completed.
A new season, a new stench
The latest round of research is a five-year study, with a second season of fieldwork set to begin.
This summer, teams will monitor roughly 100 sites, stretching from Nordegg to areas west of Calgary.
The scent lures will be set up in open clearings. Trail cameras at each site will keep watch for any visitors. Researchers will return every 10 days to retrieve footage and collect the hair.
Researchers will also analyze aromas, hoping to assess which scents might be most attractive to bears.
For years, the researchers have relied on the smell of rancid cow blood. Bears love the stench, but the blood is often a pain for the humans involved, Fernández-Bellon said.
“Cow blood is obviously messy. There are health concerns. It’s not a thing you can go round to your corner shop and buy so we are testing different attractants,” he said.
This year, his team is trying some alternative bait options, including scent lures designed for hunting.
Cow’s blood will be on the menu, but there will also be a commercial-grade fish fertilizer and bear bait, both molasses-scented and a berry mix. Researchers will also try two anise oil options that smell distinctly of licorice — one store-bought, the other homemade.
“That’s part of our work toward fine-tuning our methods,” Fernández-Bellon said.
“We’re letting the bears have a vote and decide which one they like best.”
Gordon Stenhouse, a grizzly bear biologist who founded the hair-snag research project decades ago, said consistent monitoring is critical to ensuring the species can thrive.
Habitat loss remains a threat and the province must meet its commitment to track grizzlies, he said.
“We need to monitor because we continue to see landscape change through not only industrial development, forest harvesting and oil and gas, but also now with major forest-fire events and climate change,” he said.
Stenhouse said the genetic database is a rare scientific asset that took years of labour and investment and should be maintained.
“Ultimately we want to continue,” he said. “If we just stop, in 10 or 15 years we’ll be back to Square 1, and no one wants that.”