Big increase in failure of natural food sources may be linked to global warming and has led to more bears wandering into towns in search of food
By Bob Berwyn
SUMMIT COUNTY — State biologists aren’t exactly sure why the number of human-bear encounters has jumped in the past few years, but climate change may be part of the reason.
“We’re not climate scientists,” said Colorado Division of Wildlife spokesman Randy Hampton. But an increasing number of food failures could be linked with climate trends predicted under many global warming scenarios, he said.
“We’re concerned that Aspen is the front runner,” he said. While Summit County doesn’t have the same amount of ideal bear habitat, the number of in-town sightings has also grown here in recent years, and local ordinances aimed at abating nuisance human behavior that attracts the animals are only sporadically enforced.
“We’ve had more frequent weather issues that have led to food failures. We used to see them once about every seven years,” Hampton said, referring to conditions that may wipe out or drastically reduce some of the natural food bears rely on. “About 10 years ago, we started seeing catastrophic food failures every three years. For the past six years, it’s been every other year,” Hampton said.
In some recent years, the weather has warmed well above normal early in the spring, spurring early growth of shrubs and berries, Hampton said. But then a hard freeze comes along and kills most of the berries or fruit. In another recent example, the amount of moisture in June around the Aspen area led to a fungus blight that destroyed most of the wild berry crop. As a result, the bears roam into town to find alternate food sources.
None of this has been tied directly to global warming, but most of the climate prediction models say that, at the very least, the weather will become more unpredictable and tend toward more extreme events.
Whatever the cause, the frequent showdowns between bears and humans in the Aspen area has led state biologists to propose an increase in the number hunting licenses in the area from 630 to 1,100. Last year’s licenses resulted in 33 kills, so about 5 percent of the licensed hunters were successful in finding their quarry. The agency hopes to raise that total to about 55 with the addition of the new licenses.
The idea is to thin out the population of bears around town, thereby hopefully decreasing the number of bears that wander into residential areas. Last summer, wildlife officials and other law enforcement officers had to kill 20 bears in the Aspen area, a number that convinced the division of wildlife that they need to do something.
“We’re flat-out not going to do that again,” Hampton said.
Hampton said that, along with the proposed increase in licenses, the agency is intensively studying bear populations in the area to get a better understanding of their habitat and total numbers. The agency will also expand outreach efforts and the City of Aspen recently beefed up a local ordinance aimed at cutting confrontations between people and animals.
For now, the biologists don’t know the exact number of bears around Aspen, but they’re convinced that the population is healthy. The habitat is ideal, and that’s part of the problem, as human development expands farther out of the Roaring Fork Valley’s urbanized core and into what Hampton called the transition zone.
“People have built homes in the middle of berry patches. We don’t know if other areas could be as problematic, but it’s on our radar screen,” he said.
Another factor could be the transition from agriculture to real estate in rural western Colorado,” Hampton said. When large ranches dominated the landscape, ranchers helped keep the bear population in check with permitted hunts aimed at protecting their livestock. That obviously isn’t happening as those same ranches are sold and subdivided by developers.