Summer is the peak season for problems with mountain lions in urban areas, and it's generally the young cats that cause trouble. "More than 90 percent of my problems are with juveniles, lions that are younger than two years old," says Wenum.
In the summer, prey is more dispersed across Montana and cougars must travel much farther to find a meal. August is an especially tough time for young lions that have been left to fend for themselves.
"These youngsters are inexperienced hunters, and the most important thing is to let them know that homes and ranches are not places to find an easy meal," says Wenum.
In many cases Wenum scares away the lurking cougars with a barrage of beanbag shells and rubber bullets fired from a shotgun. He chases them and uses a pack of hounds to tree them. "Beanbag rounds and rubber bullets sting, and being chased up a tree is no fun," says Wenum. "However, we want them to have a negative association with people."
In cases where livestock have been killed and people threatened or injured, the cougars are usually killed, says Wenum.
"We take a hard stand with cougars," he says. "These animals are looking for something to killit could be cats or dogs, but it could also be children or adults."
Based on hunter surveys and yearly harvests, Wenum says the cougar population in western Montana is estimated between 5,000 to 7,000 lions. Exact numbers are hard to come by because the secretive nature of mountain lions makes them particularly difficult to count, but a ten-year study to determine their numbers is in progress.
The population consists of roughly equal numbers of males and females, and of the animals that are harvested there is a wide distribution of agesyoung, old, and middle-aged. This tells us that the population of mountain lions in Montana "is in good shape," says Wenum.
As for bears, removing an easy food source in an urban area avoids the problem of unwanted visits about 80 percent of the time, says Wenum. For repeat offenders, Wenum is developing new techniquesaverse conditioningto modify the behavior of troublesome individuals.
The approach entails trapping the offending bear in a giant barrel-shaped trap that has a gate triggered by the motion of reaching for bait. Once the bear has been captured, it is drugged and held overnight. That gives Wenum an opportunity to take blood samples for genetic analysis and to place a radio collar on the bear.
Once the trapped bear recovers from the drug, Wenum takes it back to the place where it was captured and showers it with beanbag shells, rubber bullets, and a ruckus of yelling and barking. He then releases Karelian bear dogs, bred in Finland for hundreds of years to hunt brown bear, which chase the bear into the forest. "[The dogs] instinctively want to find bears and chase them up trees," Wenum says.
"I want the bear to have completely recovered from the drugs so that it realizes that it is people doing this to him," says Wenum.
The aim is change the bear's response toward the place where it was capturedfrom a place associated with a good meal to one associated with dogs, yelling, and a stinging assault.
So far the method seems successful. Of the 470 bears that Wenum has collared and released using this approach, less than 2 percent have been involved again in urban intrusions.
Wenum hopes the conditioning approach, which is still being developed, will eventually be found effective and adopted by other states so the number of bears killed in urban areas can be reduced.
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