When the Red Fox Comes to Town
The colorful canine is finding that suburbs and cities make good homes
- Peter Taylor
- Jun 01, 2001
DURING THE SPRING OF 1998, Don Miller discovered that a red fox family with eight kits had taken up residence in his suburban backyard near Chicago. The retired heavy-machinery salesman was delighted. "The kits romp out back and are very enjoyable to watch," he said. "The mother is friendly and will come lie on our deck in the sun." So charmed were Miller and his wife that they practically stopped watching television to view the fox family's nearly nonstop antics.
The Millers are not the only ones with new furry neighbors. Across the United States, as well as in many other parts of the world, red foxes increasingly are thriving in suburban and even urban areas. The specific reasons vary from place to place, but the bottom line is that the animals, like squirrels, raccoons, jays, white-tailed deer and a handful of other critters, tend to do well in habitats that have been heavily altered by humans. Equally important, says Canadian ecologist and red fox expert J. David Henry, the graceful carnivore is "one of the most flexible and adaptive species on Earth."
Like the Millers, people often welcome the sight of these beautiful, diminutive members of the dog family in their yards and nearby parks. And in many of these areas, the impact of red fox colonization on the neighbors ranges from neutral to beneficial--when the foxes provide new sources of entertainment or help control outbreaks of pests such as mice, for instance. But in a few parts of the country, namely regions to which red foxes are not native, the animals can upset local ecosystems, even preying on the occasional endangered species. "Because they're small predators with a fast reproductive rate, red foxes can dominate other species once they become abundant," says Ron Jurek, a wildlife biologist with the California Department of Fish and Game.
Scientists do not know precisely how abundant or widely distributed red foxes were in North America before European colonization. Because dense forest--rather than the fields and woodland edges the foxes prefer--covered much of the virgin landscape, the species probably was uncommon in most places. Foxes certainly did not range as widely across the continent as they do today. The animals were so scarce on the East Coast, in fact, that colonial sport hunters supplemented native populations by importing red foxes from Europe.
Today red foxes are considered the most widely distributed carnivorous mammal in the world. While no comprehensive global or regional censuses have been conducted, they are known to range across the entire Northern Hemisphere, from North America across Europe and Asia. In the 1800s, the animals also gained a foothold in the Southern Hemisphere when they were introduced to Australia for hunting. Though unique subspecies can be found in particular regions, all red foxes belong to a single species, Vulpes vulpes.
While the species' geographic range is unquestionably expanding throughout the world, red foxes are not necessarily increasing in number everywhere they live. According to biologist Todd Gosselink of the University of Illinois at Urbana-Champaign, fox populations actually have declined in many rural regions over the past two decades, while sightings in cities and suburbs have increased.
In Illinois, for example, he says that red fox numbers began to drop statewide during the 1970s--at precisely the same time that coyote numbers began to increase. Gosselink, who is studying ecological and behavioral differences between urban and rural foxes, suggests that the coyotes, which do not tolerate red foxes within their territories, may have pushed the competing carnivores out of some rural areas and into urban ones, where they are now thriving.
"People start seeing red foxes more often, and they assume that the population is up," says Marsha Sovada, a wildlife biologist with the U.S. Geological Survey's Northern Prairie Wildlife Research Center in North Dakota. "In reality, the coyotes may have taken over the rural habitats, so the foxes are forced into more urbanized places."
Red foxes fare well in these suburban landscapes. Golf courses, parks, gardens, lawns and even cemeteries offer a bountiful supply of the predator's favorite foods: mice, ground squirrels, voles, rabbits and other small mammals. Unless the predators are hit by an outbreak of sarcoptic mange (more common in urban than in rural areas), this combination of abundant prey and the absence of coyotes fosters excellent survival rates and high population densities. Even so, says Gosselink, "Most people have no idea that foxes are running around in their yards at night."
But the fox's basic physiological and behavioral traits may be the real key to its success. In his book Red Fox: The Catlike Canine, Henry, an unabashed fan of his study subject, writes: "Aesthetics and adaptation are one in the red fox--its most exquisite features are also some of its most important tools for survival." Such features include the animal's long, tapering limbs, gazellelike body, uncanny auditory acuity, speed and physical agility. The fox's legendary cunning comes into play, too. Whether stalking prey or eluding its own predators, this species often outfoxes even its craftiest adversaries, including humans.
The predator's prolific reproductive rate doesn't hurt, either. Although red fox litters average about five kits, they may boast as many as a dozen. During March or April, following a 50-day gestation period, a vixen gives birth to her young in an underground den--either excavated by the parents or borrowed from a woodchuck or other burrowing animal that abandoned it.
Blind at birth, the kits weigh just three and a half ounces each and have gray rather than red hair. For their first month, they remain in the den. Once weaned, the kits leave this cozy nest and begin to work on their hunting skills, growing the species' signature red coat at the age of two months. By winter, the young foxes have left their parents to establish their own territories, either nearby or miles away. The following spring, a vixen gives birth to her own kits, whose father will remain her mate for life.
Though they are most active between dusk and dawn, red foxes may be seen any time of day or night. The predators patrol well-defined territories, defending them vigorously against intruding foxes. Capable of sprinting 45 miles per hour and leaping 17 feet, these lissome creatures feed upon a wide range of prey. According to Sovada, red foxes "will eat anything--insects, birds, mammals, sunflower seeds." With such a catholic diet, she adds, the animals are virtually guaranteed ample food, "opportunistically feeding on whatever's out there."
When whatever's out there happens to be an outbreak of pests, be they rats, mice, ground squirrels or grasshoppers, red foxes can help solve the problem, earning them accolades from their human neighbors. If, on the other hand, the easiest prey is a rare bird species--or one that sportsmen like to pursue--the species quickly becomes public enemy number one. In a study conducted between 1968 and 1973 in Iowa, Nebraska, Minnesota, Wisconsin, the Dakotas and Manitoba, for example, Northern Prairie Wildlife Research Center biologist Alan Sargeant and colleagues found that foxes annually consumed about 900,000 common ducks such as mallards (in addition to "billions of mice and other rodents," Gosselink is quick to point out).
In coastal California, where red foxes traditionally were rare, the story was more troubling. Descendants of fur-farm inhabitants and hunt-club escapees from elsewhere in the state, these predators began to show up regularly around San Francisco Bay in the 1980s. Soon after, local wildlife biologists noticed perilous declines in some already-rare ground-nesting birds, particularly the marsh-dwelling California clapper rail.
According to Joelle Buffa, a wildlife biologist at San Francisco Bay National Wildlife Refuge, clapper rail numbers fell from 1,500 in 1980 to fewer than 300 birds in 1991. (Before that, the birds' populations already had been decimated by habitat loss.) She and other U.S. Fish and Wildlife Service biologists blamed the decline on predators--rats, raccoons and feral cats as well as red foxes. And Buffa says that nonnative foxes single-handedly wiped out a nesting colony of California least terns at Oakland Airport, a Caspian tern colony in southern San Francisco Bay and a heron and egret rookery on Bair Island.
Red fox expert Henry maintains that such occurrences are unusual, taking place only when large numbers of birds, eggs and hatchlings are concentrated in a very small area--often as a result of habitat alteration by humans. His own studies, based on observations of more than 450 hunts over several years, showed that red foxes nabbed birds only two percent of the times that they tried.
In the case of the California clapper rail, hunting conditions for red foxes were ideal: lots of vulnerable, ground-nesting birds and their young crammed into too small an area. Following the publication of a comprehensive environmental assessment in March 1991--concluding that predators, especially foxes, were to blame for the latest rail decline-- government officials launched a vigorous predator-management program in San Francisco Bay National Wildlife Refuge. The effort involved trapping and removing foxes, raccoons and other carnivores as well as constructing exclusion fences and restoring salt-marsh habitat so the birds would not be so vulnerable. Since the project's launch, clapper rail numbers have more than doubled.
Meanwhile, back in Illinois, the Miller family had a few problems with their own foxes that they, too, have managed to solve. When the animals began digging up his spring flowers a couple years ago, for instance, Don Miller called local wildlife experts, who suggested sprinkling mothball flakes along with flower seeds to deter the foxes. The scheme worked, and now he and his wife warmly welcome the foxes back each year, even provisioning them with popcorn treats. "If the foxes want to come and lie around my yard, it's fine with me," says Miller. "We like the animals."
Maine journalist Peter Taylor wrote about coral reef restoration in the October/November 2000 issue.
NWF Priority
Teaching Awareness Of Nature in the City
Red foxes are one of several wildlife species that students in U.S. metropolitan areas learn to appreciate through three innovative NWF NatureLink® programs: Earth Tomorrow® clubs for high school students; Teen Adventure™ clubs for middle school pupils; and Ranger Rick's® EarthSavers® clubs for elementary school children. All three introduce students to the natural world around them while also helping them design local conservation projects.
In one project, students in Detroit recently planted blue lupine in inner-city schoolyards as habitat for endangered Mitchell's satyr butterflies, which deposit eggs on the plant's leaves.
In another, children from economically disadvantaged areas in Washington, D.C., meet weekly at a youth center, where they learn to identify native birds and other wildlife.