An episode of NBC’s “Wild Child” that aired Dec. 4 featured various species of wildlife that have adapted to urban environments. Among them was the red fox.
Scientists have known for a while that prey animals sometimes hang out near humans because most predators avoid people like the plague. What the prey animals do is called the human shield effect. And while the red fox is a predator, it’s believed they are moving into areas of dense human development seeking refuge from a bigger, stronger predator: the coyote.
In decline
As Europeans settled in what is now Ohio, they cleared more than 80% of the forest. In the process, 15 native mammal species disappeared including elk, wood bison, wolves, cougars, bobcats and bears. Coyotes were considered more of a western species, but as the other large predators disappeared, coyotes moved in. They were first documented in Ohio in 1919.
Though they’re still listed as “common” in Ohio, red fox populations have been declining both here and in the eastern United States. The Ohio Division of Wildlife keeps track of red fox numbers through yearly bow hunter surveys. The number of red foxes spotted in those surveys has declined steadily since they began in 1990.
Biologists say that’s due at least in part to coyotes increasing their range and their numbers. Bigger and more muscular, coyotes can out-compete the fox for food and territory, even killing them and their young. But recent studies, including one conducted in the Cleveland Metroparks in 2015 and 2016, show that human development seems to be giving the foxes a bit of a break.
As predators, both red foxes and coyotes try to avoid humans, but coyotes seem to try harder.
Metroparks study
Stan Gehrt, wildlife ecologist with Ohio State University, led a study in a Canadian national park where nearly two dozen coyotes were fitted with collars to show their movements.
The study found that coyotes largely avoided areas of the park frequented by people. And during times when people’s use of the park was at its highest, the coyotes tended to limit their activity to nighttime hours. That’s called temporal segregation. The Metroparks study monitored both coyotes and red foxes with 104 cameras that specified whether their activity occurred in the day or night. The results showed that both the foxes and coyotes practiced temporal segregation, but coyotes much more so.
The Metroparks were chosen for the study because their 24,500 acres are scattered across the Cleveland area, with a population of about two million people. Some of the 18 parks border natural environments, but more are situated in busy urban and suburban areas.
Preference for people
The study found that the more developed the area surrounding a park, the more likely red foxes were to be caught on camera, seeming to occupy that territory. This supports the theory that “urbanized areas serve as a refuge that allow red fox to persist even in the presence of coyotes,” the authors wrote.
“Both red fox and coyotes try to avoid us, but the red fox really tries to avoid coyotes,” said Jonathon Cepek, wildlife ecologist for the Cleveland Metroparks and second author of the study. “To the red fox, people are less threatening than coyotes.”
So the red fox may be using humans as shields, but why are coyotes also choosing city life? Some studies show five times the number of coyotes in urban vs. natural environments, while in parts of California, a study documented eight times as many, Cepek said.
“If we look at census records between 1800 and 1900, the European settlers brought the population of Ohio to almost five million,” he said. “As of 2010, the population was 11.5 million, more than double.”
Change in environment
Now more than 70% of Ohio’s humans live on less than 10% of the land, i.e. in developed areas. And those people have changed the environment significantly for both the coyote and red fox, Cepek said.
“We’re constantly providing food resources in our backyards,” he said. “We have gardens, compost piles, bird feeders and pet food left outside.”
While both foxes and coyotes are technically carnivores like wolves and cougars, their smaller body size allows them to be more flexible in their diets. Even if they are not preferred foods, both will eat fruit, seeds and even grasses.
“If we leave pet food out at night, they’ll sneak in for an easy meal,” Cepek said. “So human behavior changes their behavior.”
And more food resources mean an increased number of small mammals like squirrels, chipmunks and mice, which are preferred foods for the two species.
“If you have these food resources available, why waste energy and risk injury by fighting and chasing others away?” Cepek said. “The human influence is throwing things out of whack.”
It is a weird scenario for both species, which didn’t have to compete with each other hundreds of years ago. Back then, the gray fox was thriving in the dense forests that were common in the East — and what would become Ohio — until European settlers arrived.
The red fox, on the other hand, prefers “edge habitat” between forest and field, or open areas and grasslands. They weren’t really in this area in pre-settlement days, instead inhabiting areas to the north. As the forests were cleared, the populations of gray foxes declined.
Meanwhile, aristocratic settlers were quick to bring red foxes from Europe to hunt with horses and hounds. But they don’t deserve as much credit as they’ve been given for the red fox’s population gains in this area.
“Probably 30 years ago, the common belief was that red foxes in the eastern United States were descended from those brought over from Europe,” said Katie Dennison, wildlife biologist with the Ohio Division of Wildlife, whose responsibility is monitoring, research and management of Ohio’s 16 furbearer species.
Now scientists believe that clearing forests, as well as the removal of apex predators like the wolf, cougar and bobcat, allowed the red fox to move in from what are now the northern states and Canada.
“There is currently more evidence for the migration theory, although it’s still possible that some of our Ohio red fox are descendents of those brought from Europe,” Dennison said.
Regardless, red fox populations increased and the gray fox’s decreased as Ohio’s forests were cleared for farmland. Today the state’s largest populations of red foxes can be found in the agricultural areas of Northwest and Central Ohio. However, they can be found in all 88 counties, even in the more heavily-forested areas of Southeast Ohio, Dennison said. And as the Metroparks study showed, they have adapted to urban and suburban areas as well.
Not villains
Though portrayed as a villain in fables and fairy tales, the red fox’s behavior is really quite admirable. They are monogamous in mating and the males help raise the young, called kits. Mating in Ohio usually takes place in January and February with the kits born 50-some days later. The mating pair only have one litter per year, usually, with five or six kits, Dennison said.
The female does the heavy-duty construction on the dens, which in natural areas can be several feet deep and quite spacious. The male brings food to the den until the kits are weaned. Then it’s time for the whole family to go on hunting trips, with both mom and dad teaching survival skills.
The family breaks up in the fall, with the young going their own way and the parents living separate, very solitary lives until it is time to mate again. In natural and rural areas, their range is between one and two miles, Dennison said.
For red foxes living in urban areas, their range is much smaller. And as the episode of “Wild Child” pointed out, they must compete with at least 14 other species in that reduced space. Still, they seem to be surviving and thriving in these cramped quarters.
“Red fox populations do not appear to be declining in Cleveland Metroparks,” Cepek said.
