Early last Monday morning, Carl Lackey set out to catch some black bears. He was on the trail of a mother and two cubs that had torn up a chicken coop in Reno, Nevada. The biologist with the Nevada Department of Wildlife has had plenty of practice in catching, tagging, and releasing bears recently, as the animals have been venturing into towns in search of food.
"We’ve caught 125…130 this year,” says Lackey, who has worked with the burly omnivores for 18 years. He says it’s the second-busiest year on record for snagging bears that come into town, after 2007. Both these periods of bears-gone-urban coincide with times of drought.
The West is in the grips of a three-year dry spell that has diminished the animals’ natural food sources, such as acorns and berries. The hibernators are now on the hunt for extra calories before they take their long winter nap—a lot of extra calories, upwards of 20,000 (that’s the equivalent of about three dozen Big Macs). And the gluttons are leaving a trail of destruction in their wake.
“We’ve got bears breaking into homes and cars in Tahoe,” says Lackey, whose team has had to euthanize two bears that had become too aggressive toward humans. “In the Reno-Carson area, they are feeding on apple trees in the middle of town and going into backyards to feast on koi ponds and bee hives.”
Bears were most troublesome in October, but their breaking-and-entering activities have been tapering off as they head into their winter dens. Lackey suspects that drought drives some to go into hibernation a bit earlier in order to conserve energy, “and others to stay up later trying to put on that extra inch of fat.”
Across the border in California, Jason Holley, a biologist with the Department of Fish and Wildlife, says he hasn’t seen any signs so far that the hibernation cycles of Golden State bears will differ from previous winters. He says California is so big that when bears go down—and wake up—varies from place to place. Those in the high Sierra settle into their seasonal slumber earlier and sleep longer than bears in southern California and other lower foothill communities.
As for whether a warm, dry winter—as NOAA predicts—might send bears throughout California out of hibernation early, it’s too soon to say. “Bottom line,” says Holley, “we can't be certain what to expect until next spring.”
Lackey agrees that only time will tell how black bears fare, but he says that while the Sierra Nevada population is healthy and on the rise, some of the drought-affected animals likely won’t make it through the winter. Others will emerge earlier in the spring, in late February, or early March, with a bear of an appetite.
And some won’t bother bedding down for winter at all—like this this black bear that startled skiers in Tahoe last January when it lumbered across a racecourse. But skipping hibernation probably isn’t due to the drought, since this behavior has been going on for about a decade. Black bears as far away as Florida have also developed a touch of insomnia in recent years.
These deep-sleep dodgers have most likely acquired a taste for garbage. This food supply, unlike the natural food supply, doesn’t diminish, so the bears may become restless all winter long. That junk-food diet has other downsides, too: Bears dining on trash are less active than their counterparts and die younger, in part because they come into conflict with people.
“Every year we have a handful of bears active all winter, unfortunately,” says Lackey. “They feed at night, foraging on garbage, then go back and find a daybed under somebody’s deck or other hideaway for a couple days, then get up again.”
When the hungry bears do wake, they inevitably head toward towns. But that doesn’t mean they have to find food there.
“It’s frustrating,” says Lackey. “People don’t want to do anything until bears start knocking on their front door”—or in some cases rip apart their garage or claw through their exterior wall—“and only then do they get a bear-proof trashcan.”
And as for those three bears he was pursuing last week, they’re still on the prowl.
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