GLENWOOD SPRINGS - On June 11, 2012, Perry Will already knew it would be a bad year for bears. The previous night, a hard frost had settled over much of western Colorado, nipping thousands of acres of the chokecherry, serviceberry and acorn-bearing oakbrush that bears in the western Rockies rely on for food.
That meant one thing: the creatures were coming to town.
Will, a 38-year veteran of Colorado Parks and Wildlife, a division of the Department of Natural Resources, manages a three-county part of western Colorado called Area 8. It includes eastern Garfield County, and all of Eagle and Pitkin counties.
In his 38 years in wildlife management, Will has never seen a bear season like 2012: Through November of this year there were 100 bears killed, up from just 32 in 2011. In 2009, another dry year, the total was 59.
"Years ago, those kind of numbers were unheard of," he said, sitting in his Canyon Creek office on a recent December day. "We've got more bears now than we've ever had."
Just down the hall from his office, a large whiteboard covered in red ink spells out the details. On it were descriptions of all the bears killed by motorists, private landowners, accidents and Colorado Parks and Wildlife agents in Zone 8 this year. Each listing included gender, tag number, date and place of death.
CPW Public Information Officer Mike Porras said the department has kept comprehensive bear records for only a few years.
The primary culprit for those conflicts in 2012, according to Will, was the late killing frost, combined with the year's historic drought.
"When those plants are stressed, they don't produce," he said of staples of the bruin diet. "And in August, when bears need to be consuming 20,000 calories a day, you can bet that you'll see them in town."
More bears in town, of course, leads to more conflict with humans, which means more bears tagged by wildlife agents or shot by angry landowners. And if Will's agents find a tagged bear causing trouble again, they will put that animal down.
Data suggests that the problem is sharply reduced in historically wet years. In 2010, for instance, the CPW recorded just 18 bear kills.
The bears most likely to seek human food in any year are what Will calls "teenagers," the previous year's cubs that have just been kicked out of the den by their mother.
Seeing older animals with established territory come into town, Wills said, is a sign that food is scarce in the backcountry.
"When you see a big dominant male in town, you know it's rough out there. If there's good natural food out there, they tend to want to be bears," he said. That means sticking to their natural food sources, and avoiding humans.
When CPW agents tag and relocate a bear, they transport it at least 50 miles from where it was found, so that it doesn't immediately return to the scene of a conflict.
Yet due to Colorado's healthy bear population, agents who move bears are bound to drop them in the middle of another animal's territory. At last count, Will said there are roughly two bears per square mile of habitat.
"There is literally no open bear territory in Colorado right now," said Will.
Bears have strong homing instincts under any circumstances, but clashes over territory make it even more likely that they will migrate back to their native territory, or migrate long distances in search of food.
"It's during that travel that they usually come into contact with humans," said Porras.
Some factors behind the state's surging bear population remain mysterious, but increased familiarity with humans - and a willingness to go after their food - is playing a role, says Will.
After years of living with bears, most Coloradans are familiar with proper etiquette: keeping trash in bear resistant containers, keeping pet food inside, and cleaning barbeque grills, for instance.
Yet Will says that even if most people are careful not to tempt bears close to their homes, a single transgression is enough to send the wrong message.
"You can't have 95 percent compliance," he said. "If you don't have 100 percent compliance, the bears still get rewarded."
In lean food years, Will said, bears tend to emerge from hibernation early, raising the prospect that they could be out searching for food next spring as early as March.
It's unclear how this year's thin food crop will affect the spring cub population. When severely malnourished, mother bears can either absorb their cubs in the uterus or give birth to runts, which are unlikely to survive.
For now, the population remains historically high. Porras said a study is under way to get a better idea of the bear population in Zone 8.
In an attempt to control bear numbers, wildlife officials have been increasing the number of bear tags issued to hunters in recent years.
"The science says that if you are approaching 40 percent females in the hunting take, you back off," said Will. "But that may not be enough."