Beyond Friendly Problems With Aggressive Animals Usually Start With Uniformed People

A teenage angler was cleaning a fish at the cleaning station at a marina on Yellowstone Lake about 10 one recent night. Then a pair of coyotes trotted out of the fresh darkness and kept coming.

The boy dropped his fish, and one coyote grabbed it. Then the other one bit him on the thigh, tearing his pants and scratching him a little.

Rangers tried for a week to capture and kill the coyotes, but they were too wary, said Dan Reinhart, a management biologist.

“Habituated” animals have been a problem in the park for years. Animals that become too comfortable around people can become annoying or dangerous for tourists and often bring harm to themselves as well.

Another coyote was causing problems in the Mammoth Hot Springs area recently, following small children and small dogs. That animal got off easy. Biologist Kerry Gunther, who helps manage habituated animals in the park, darted it, put an ear tag on it and shipped it to the backcountry.

As Gunther told the story in his office in Mammoth, a couple of families sat at a shady picnic table across from the dining hall. Children as young as 2 years old were feeding pretzels to chubby ground squirrels.

Could the coyote and squirrel incidents be related? Perhaps.

Before he darted the coyote, Gunther had spent two days following the animal around Mammoth, a place bustling with tourists.

“It was spending most of its time around the ground squirrels, where people are feeding them,” Gunther said.

When people feed ground squirrels and chipmunks, it leads to artificially high populations, which draw in predators, which get accustomed to people and sometimes become dangerously aggressive, biologists say.

“It starts out with habituation, and they get bolder and bolder,” Gunther said, adding that coyotes must be killed every year because they get too aggressive, sometimes biting people or jumping up on children.

Aggressive coyotes have been an increasingly common problem in recent years, Gunther said, and most of them got that way after tasting human food.

“It appears that feeding not only creates beggars but removes the fear that coyotes have towards humans, which can predispose these individuals to aggressive encounters in the future,” wrote Bob Crabtree, a Bozeman, Mont., biologist who has been studying coyotes in Yellowstone for years. “There is absolutely no evidence to suggest that coyotes are naturally beggars.”

The problems are not limited to coyotes.

Along the Madison River, where rare trumpeter swans nest, people often feed the magnificent birds, according to Park Service bird biologist Terry McEneaney.

“People come in and think they’re in a city park,” McEneaney said. “They have this need to feed wildlife.”

The handouts themselves may not hurt the swans, he said, but “when they lose their fear of people they lose their fear of predators.” Plus, the bread and other snacks lure the birds out of the water and onto highways where they risk becoming roadkill.

Ravens have also learned that people are a source of food. Snowmobilers, bundled in thick suits and heavy gloves, often drop food scraps without realizing it, McEneaney said. Ravens then associate snowmobiles with food, and that can mean serious damage from the curious and aggressive birds.

Other birds cadge scraps around picnic areas, and larger wildlife sometimes is endangered by human food, often in ways that people don’t imagine.

Bighorn sheep like bread, for instance. Gunther has heard of bighorns using their teeth to scrape mashed sandwiches from park roadways. That puts them in danger from traffic, and “it can’t be good for their teeth,” he added.

The problem is not new to Yellowstone or to other places, and wildlife managers have struggled with it for decades.

“This is a learning experience for all of us,” Gunther said. “They don’t teach any of this in wildlife management courses.”

However, there have been some notable successes in the park.

After years of aggressive enforcement and effective public education, most people know better than to feed a bear in the park.

From 1930 to 1969, bears ate a lot of human food and injured an average of 45 people a year in Yellowstone. That number is now down to an average of one injury a year, Gunther said, and those injuries usually happen in surprise encounters that are difficult or impossible to avoid.

That success hasn’t spread to other animals, possibly because they lack the dangerous reputation that bears have. And enforcement of feeding bans has dropped in recent years.

All park visitors receive a newsletter that tells them not to feed any animals. But rangers rarely cite people who ignore the warnings.

Some biologists call for more enforcement. But changing people’s behavior won’t be easy.

“The only real contact with the environment, for a lot of people, is feeding,” McEneaney said. “People just have to remember where they are. The best advice is just don’t feed wildlife.”