Foxes and Coyotes are Natural Enemies. Or Are They?

Urban environments change the behavior of predator species—and that might have big implications for humans

An urban coyote makes itself at home in a vacant lot on Chicago's near North Side. Todd Bannor / Alamy

A pair of burly coyotes is one of the last things you expect to see in the concrete jungle, especially in the largest city in America. But that’s exactly what I saw one evening at the edge of the New York Botanical Garden.

They looked huge, with shaggy brownish-gray fur, and completely unafraid. The pair trotted on either side of me, staying about 10 feet away for several minutes before eventually running off. Before I could decide whether to grab a stick or start shouting to scare them off, they were gone. A short while later, two young women ran shrieking from one of the garden’s forested areas. I suspected they’d just had a similar experience.

My next encounter was in Chicago, in a narrow park along the North Branch of the Chicago River that threads its way between residential areas. I jogged past a coyote nosing around the playground, seemingly oblivious to my presence. Minutes later, another woman on the trail stopped to warn me of the animal’s presence and ask if I’d seen it. Once again, it seemed like an aberration to both of us: a wild carnivore in the heart of a city of 2.7 million people.

Several years ago, a flood of similar reports occurred in Madison, Wisconsin, prompting wildlife biologist David Drake to study the city’s urban coyote population. To understand the implication for humans, Drake also wanted to see coyotes’ behavior towards competitors, like the red fox. Red foxes are hunters and flexible foragers, eating rodents and birds as well as fish, frogs or garbage. In rural settings, the smaller foxes avoid coyote territory; although coyotes won’t eat foxes, they do kill them to prevent them from causing resource scarcity.

Over a two-year period, Drake and a group of researchers followed 11 coyotes and 12 red foxes that they’d harnessed with radio collars. Their results, published recently in the journal PLOS One, came as a surprise. “If you look at the literature in non-urban areas, most studies suggest coyotes would displace red fox. If coyotes can catch the red fox the will certainly kill them to limit competition for resources in that area,” Drake says. “We pretty quickly realized there was something different going on in these urban areas.”

Foxes and Coyotes are Natural Enemies. Or Are They?
An urban red fox sniffs trash bags for food scraps at night in a London garden. Dominic Robinson / Alamy

In many cases, animals forced to live in small urban environments come into conflict with each other, both between and within species. Take tigers, for instance, whose shrinking territories can lead to adult males killing any cubs that aren’t their own.

But that’s not happening here. Despite having less room to establish their home ranges in cities than in the countryside, the coyotes and red foxes in Madison seemed less antagonistic towards each other than in more spacious environments. At one point, the researchers observed a male fox and a male coyote hunting in the same field, sometimes coming within 20 yards of each other. Yet the coyote didn’t attack the fox to scare it off, and the fox didn’t appear intimidated enough by the coyote’s presence to leave.

On another occasion, the researchers witnessed coyotes visiting a fox den—perhaps because the foxes were bringing dead rabbits or other food for their kits and the hungry coyotes were taking advantage of the easy meal.

“We knew of at least four other fox dens in that territory that they could’ve easily moved kits to, and they never, ever moved them, even when coyotes were showing up just about every other day,” Drake says. The foxes, it seemed, just didn’t feel vulnerable enough to go to the trouble of moving. It fit the broader pattern of their research: not a single aggressive encounter between coyotes and foxes.

What could explain the changed behavior? Drake and his colleagues’ initial hypothesis has to do with the availability of food. Thanks to urban landscaping, herbivore species like rabbits, deer and mice have a bounty of food options, and the plants get replaced even after they’ve been eaten thanks to green-thumbed humans. In addition, humans leave compost piles, garbage cans and pet food outside, a veritable buffet to omnivorous animals. Instead of foxes and coyotes fighting for scarce resources, this theory goes, they coexist more peacefully thanks to the human-created abundance.

This newfound abundance has disrupted animal behavior in more than just foxes and coyotes. Take, for example, a recent hypothesis called the predation paradox. In a variety of urban environments, the density of predator species (be they bird or four-legged beast) hasn’t resulted in higher rates of predation. In other words, the prey populations that should be decreasing thanks to greater numbers of predators are remaining at the same level as before the influx of hungry carnivores and omnivores.

“There’s this idea that in urban systems you have a lot of different food resources available, and many of the predators of bird nests are generalist predators—raccoons and opossums and crows,” says Amanda Rodewald, a professor of conservation and natural resources at Cornell University and the author of a 2011 study on the predator-prey relationship in nest birds around Columbus, Ohio. Her study found that nest survival decreased in rural landscapes with the presence of more predators, but the same effect didn’t hold in urban environments.

Urban coyotes are unusual in that they seem reluctant to eat human food, even when it’s readily available. Mostly they stick with their traditional diet of small mammals and bird eggs, and they still act as predators with a controlling effect on the populations of prey species, like Canada geese and white-tailed deer, says Ohio State University wildlife biologist Stanley Gehrt.

For more than a decade, Gehrt has studied urban coyote behavior in Chicago, looking at how the canids interact with raccoons, with free-roaming cats, and with one another. In several cases, there has been less competition between coyotes and other predators than might be expected, thanks to the abundance of food. That same abundance sometimes means a greater number of predators living in the area overall.

“One of the characteristics of the urban system is the lack of larger predators. That really important ecosystem function has been missing until the coyote moved in,” Gehrt says. Coyotes are particularly good at making their way into urban environments, compared to other large carnivores like mountain lions or bears, because they learn how to work around roadways and traffic patterns, Gehrt says.

What all this means is that coyotes, foxes, raccoons, possums and other predators have settled into city life and won’t be leaving anytime soon. That’s why Drake and others have enlisted citizen scientists in their efforts to study coyotes and other predators. It’s as much about educating the public as it is gathering data.

Of course, there are costs to living in close proximity with wildlife, whether it’s the destruction of a lovingly tended garden or the death of a family pet. Research also suggests that more contact with wildlife increases the risk of zoonotic diseases like Ebola or Avian flu, which jump from animals to humans. But we won’t know the extent of the problems, and the benefits, unless more resources are funneled toward looking at the under-studied realm of urban wildlife. The relatively new field has been neglected in part because wildlife research is often funded by hunting and game associations, Gehrt says.

With around 85 percent of Americans living in urban areas, the chances of encountering wildlife in the concrete jungle are high. We need to understand what normal behavior looks like versus the behavior of a sick animal. And when the animal is behaving regularly, we need to be able to enjoy the experience of seeing them rather than feeling fear. “The way these animals live in urban areas is much different than how they live in rural areas,” Drake says.

That comes down to public education and more funding for research—both ongoing challenges for wildlife biologists. For Gehrt, it’s worth keeping in mind the positive impact of urban coyotes. Coyotes help control herbivores that might otherwise have huge populations, and they don’t generally harm humans. “The benefits probably outweigh the costs of having predators in our systems,” he says.

Drake agrees. “I feel that my life, and hopefully most people’s lives,” he says, “are enriched by having these animals around us versus having a city devoid of wildlife and natural resources.”

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