Grizzly bears have keen noses – far keener, in fact, than a bloodhound’s. The big bruins literally sniff their way through life, relying on their sense of smell to find distant mates and remote food sources.
So, to count the number of grizzlies in the Cabinet-Yaak ecosystem, researchers turned to a distilled essence of fish guts and cow’s blood. The liquid is sprinkled on logs surrounded by barbed wire. When the bears crawl over the wire to investigate the scent, they unwittingly leave DNA behind in clumps of hair, which will be analyzed to identify individual bears.
Anticipation built on a recent weekend as U.S. Geological Survey field technicians Regan Plumb and Libby Davis approached a “scent corral” they’d baited two weeks earlier in Idaho’s Moyie River drainage.
“Hello, bears!” Plumb called out as she neared the forest clearing. “Good morning, bears!”
The women had doused a pile of logs with the noxious-smelling brew, and hung a scented rag in a tree for good measure. But no sounds of animals crashing through the underbrush greeted Plumb’s bear calls. Gray fibers caught on the barbed wire were lichens.
Such is the nature of fieldwork. Some days, the two women come home with envelopes stuffed with wads of hair. Other days, they turn up empty.
Plumb and Davis are part of a team of 70 fieldworkers checking scent corrals spread across 2.4 million acres of North Idaho and northwestern Montana. The workers will monitor 800 such sites this summer, along with 1,200 natural “rub” spots such as trees and signposts where bears shed hair.
In distant labs, scientists will separate the grizzly hairs from black bears’ hair. (By sight, the hairs are easy to confuse, since both grizzlies and black bears come in a range of colors.)
The grizzly hairs will go through DNA testing, which will yield more precise estimates of the Cabinet-Yaak population, currently believed to be at least 40 to 45 bears. The data will also reveal gender and information about family ties.
The study was designed by Kate Kendall, a scientist for the U.S. Geological Survey at Glacier National Park. She used identical methods several years ago to count grizzlies in Montana’s Northern Divide ecosystem. The 34,000 hair samples led to a revised estimate of 765 grizzlies – 2 1/2 times more than previously thought.
The Cabinet-Yaak study is somewhat unusual because it was initiated by Montana’s Lincoln County. The county commissioners are raising the $1.7 million needed for the three-year study.
“The local community really wanted better information on the status of the population,” Kendall said. “They have rounded up funding from an amazing array of partners.”
The Forest Service has chipped in money, along with other federal agencies, and state, local and tribal governments. Private industry, local retailers and conservation groups contributed, too. Study results are expected in early 2014.
“People here just want to know what the number is,” said Tony Berget, a Lincoln County commissioner.
The Cabinet-Yaak’s grizzly population was listed as “threatened” under the Endangered Species Act in 1975, but it’s unclear from official estimates whether the population is trending up or down, he said. Anecdotally, “it seems like a lot more of our friends and neighbors are seeing grizzly bears,” Berget said.
Protecting grizzly habitat has led to road closures and logging reductions, which have frustrated rural communities. In recent years, Berget thinks local residents have become more accepting of sharing the landscape with grizzlies. People seem more attuned to precautions such as not leaving out garbage, pet food or other bear attractants, he said.
But hostility toward grizzlies still exists. The May killing of a grizzly and her nursing cub at Hall Mountain in Idaho’s Boundary County was probably “a hate crime,” said Doug Zimmer, a U.S. Fish and Wildlife spokesman. A $10,000 reward is being offered for information leading to an arrest in the shooting.
Plumb and Davis said that when they’ve discussed the grizzly census project with local residents, they’ve received positive feedback. People appreciate the work they’re doing to get accurate counts.
On a typical workday, the women log 40 to 50 miles over gravel roads in a truck and hike up to 10 miles to collect hair from the scent corrals and rub sites.
The hikes take them through dark, misty groves of cedar and hemlock in the Moyie River drainage, through thickets of buffalo berry bushes and across meadows spangled with wild strawberry blooms. They’re currently checking low-elevation sites. As the summer progresses, they’ll follow the bears up the mountain to higher-elevation habitat.
Plumb, who has two young children, looks for forest babies in the woods. One day, she nearly stepped on a fawn camouflaged by its spots. Last weekend, she spotted newly hatched juncos in a nest underneath a huckleberry bush.
Tolerating mosquitoes is part of the work. And the dead-animal odor of the grizzly lure takes some getting used to.
Davis tugs a bandanna over her nose before uncapping a bottle of lure. The smell is so rank that it attracts turkey vultures, said Davis, a 20-year-old biology major at Green Mountain College in Vermont.
But the smell is a powerful bear attractant. Grizzlies have been spotted at sites within a half-hour of its application. The women will gradually add other scents to the mix – including skunk, anise oil and cherry – to keep the bears’ interest over the summer.
When they’re in the field, the women carry bear spray for protection. So far, the pair have seen only one bear. It was sprinting down a Forest Service road, and they couldn’t tell if it was a grizzly or a black bear.
Davis has had nightmares of being charged by a black bear – probably the result of a curry dish she ate for dinner, she said. She’d like to have a grizzly sighting during her time in Idaho.
“It would be a privilege to see one, knowing that there are only about 40 left in the study area,” Davis said.