Easing orphans back into the wild
Montana biologists are teaching abandoned black bear cubs to go home to the wild
Last summer, as wildfires raged in Montana’s Bitterroot Valley, a scrawny black bear cub with burned paws emerged from the smoke and flames. For three days, the youngster fed on a deer carcass and drank from a nearby creek. State game warden Joe Jaquith kept an eye on the cub, hoping its mother would show up. When no adult bear arrived, he reluctantly captured the 20-pound orphan.
Recalling the similar saga of Smokey Bear 50 years earlier, the press tried to turn this cub into the newest wildlife celebrity. But Montana authorities had a better idea: return the bear to the wild. With its paws bandaged by a veterinarian, the cub was taken to an animal shelter operated by Montana Fish, Wildlife and Parks (FWP) in Helena. There, the youngster became just another ursine orphan in the shelter’s bear rehabilitation and denning program.
Each year, a number of orphaned Montana black bear cubs are taken to the shelter. Some are held until they are large enough to fend for themselves, then released in the wild. But simply turning bears loose in the woods (called a "hard release") doesn’t always work well because the animals may travel great distances and get into trouble. "Hard-release bears tend to show up at ranch homes or even approach vehicles," says Mike Madel, a bear biologist with FWP.
In the 1970s, FWP biologist Vince Yannone developed a "soft release" technique that uses hibernation dens as halfway houses to ease cubs back into the wild. Since then, dozens of cubs have gone through the program. About half of these animals survived at least a year in the wild, the same survival rate enjoyed by cubs with mothers. "The bears we put into dens rarely come into conflict with people," says Madel.
The focal point of the program is an activity that suits cubs just fine: eating. The goal is to get these bears as fat as possible. A cub that comes in at 20 pounds in spring may by fall weigh 100 pounds--two or three times as much as a cub in the wild.
Bears live off stored fat while hibernating. "Orphaned bears also need extra weight to get them through early spring while they figure out where to find food--something a mother would normally teach them," says Kurt Cunningham, FWP education bureau chief.
Whenever possible, cubs are paired up at the facility to help replicate natural conditions in which most young bears have a sibling or two. Each cub pair is provided with a straw-lined denning box. In late autumn, shelter workers shut down the grocery buffet, simulating the fall food shortage wild bears experience. Combined with cold weather and declining daylight hours, this triggers the urge to hibernate. The cubs become lethargic, enter their boxes and begin hibernation.
However, because bears maintain a relatively high body temperature during hibernation--about 85 degrees F compared to their normal body temperature of 101 degrees F--they awaken rather easily. In January or February, biologists roust the slumbering cubs, get them into travel cages and truck them as far into the mountains as snow depths allow.
Years ago, biologists located ideal denning spots on forested public land far from human habitation. There, they excavated four widely separated dens, which now house new tenants each year.
At road’s end, one cub in each pair is usually fitted with a radio collar so they can be tracked the next spring. Then the temporarily sedated cubs are taken to their assigned den. Finally, the cubs are tucked into the den and the entrance is covered. When the drug wears off, the bears resume their hibernation. In April or May, they awaken, push their way out of the den and begin life in the wild.
This soft-release technique may also trigger a bit of beneficial amnesia. "We think having cubs wake up in a mountain den instead of a box at the shelter helps them forget about people. That can keep them out of trouble," says Cunningham.
Whatever the reasons, the denning program has given a second chance to many bears--including the cub that survived a brush with fire and with fame. Last February, the bear from the Bitterroot (then weighing a robust 90 pounds) made the long journey from Helena to a den high in the Rockies. This spring, he and his den mate emerged from those cozy quarters to begin foraging on natural foods far from human habitation. With luck, he will never encounter fire or people again.
A Montana journalist Gary Turbak wrote about elk in the February/March issue.
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