Plans are shaping up for a sixth woodland caribou transplant in March to rebuild the dwindling herd along the U.S.-Canada border.
But unlike the other five transplants to Idaho and Washington since 1986, this year’s plan calls for the caribou to hoof it across the border themselves.
The U.S. Fish and Wildlife Service has overseen the recovery project for the last free-roaming herd of woodland caribou in the lower 48 states, with help from the Idaho Department of Fish and Game and the Washington Fish and Wildlife Department.
The new wrinkle of releasing the caribou a few miles north of the border reflects a growing recognition that the herd migrates between Canada and the United States anyway. Jon Almack, a Washington Fish and Wildlife researcher at Sullivan Lake, said the animals winter on the high ridges north of the border, then head south during the summer.
The original recovery plan called for establishing separate caribou herds on the Idaho and Washington sides of the southern Selkirk Mountains to reinforce the remaining herd north of the border.
“In reality, if you look at the telemetry, there aren’t three distinct groups at all,” Almack said.
In addition, biologists say keeping the transplant within British Columbia would eliminate the need for a half-dozen separate federal permits, and might eliminate requirements that the caribou be tested for tuberculosis and brucellosis.
Less time in captivity also could reduce stress on the animals and the chances for injury.
One theory for the loss of so many of the caribou previously transplanted to the area involves habitat changes in the Selkirks from logging and forest fires that have favored the growth of white-tailed deer herds. As the number of deer increased, so did their range and their primary predator: mountain lions.
Caribou evolved in old growth forests and sought out the highest ridges, both because the trees there hung thick with old man’s beard lichen, a favorite winter forage, and because predators found little to eat there.
Now deer range from the valleys to the ridges in the Selkirks and mountain lions have followed. Every once in a while, the cats pick off a caribou. And when there are only a few caribou, any loss is a setback.