The benefits of badgers

National Wildlife, Dec-Jan, 1995 by Les Line

These burrowing prairie weasels help coyotes to hunt and may provide clues about toxic land contamination

A celebrated folklorist of the American Southwest, J. Frank Dobie until his death in 1964 collected fine stories the way some people collect fine wines, and like oenophiles he took great pleasure in sharing his treasures. In one famous tale, Dobie told of an acquaintance who "has twice seen dust rising from a prairie dog town some distance away and then, through binoculars, watched a badger digging while two waiting coyotes flanked him. In each instance the badger got meat, but a prairie dog or two came out by him into the mouths of the coyotes."

Like most Texans, the author was guilty of a stretch now and then, so experts tended to dismiss his animal yams as more fiction than fact. For centuries, however, the Navajo people had passed along stories about coyotes and badgers hunting together, and Dobie surmised that nature was hiding something important about the brash wolf's camaraderie with this cousin of skunks and weasels. He was right.

The big secret was revealed not long ago by a rare breed of scientist: a badger biologist. It's true that coyotes often run around with badgers, Steven Minta of the University of California in Santa Cruz reported in the Journal of Mammalogy in 1992. On Wyoming's National Elk Refuge, where Minta did his research, far more coyotes hunt with badgers than hunt alone. Instead of wasting time and energy stalking ground squirrels in the dense sagebrush, the coyotes simply wait for badgers to flush the rodents from their burrows. Moreover, Minta observed, badger-befriended coyotes catch a third more squirrels than do solitary coyotes.

The alliance benefits the badgers, too. Minta theorizes that ground squirrels hunker down in their holes when coyotes are standing guard, allowing the badgers to spend more time underground catching and eating prey. There's more: With their acute eyesight and hearing, coyotes can locate squirrels at a distance, allowing them to function as spotters for the ground-hugging badgers. The coyotes encourage the badgers to move to more productive digging sites by various kinds of play - mock pursuit, bowing, dancing and face-pawing. Sometimes a badger and coyote will simultaneously charge an area with a dense squirrel population, panicking the rodents and catching them above ground or trapping them in shallow and unconnected tunnels.

Coyotes sometimes kill young badgers, Minta noted, but the absence of any mutual predation among adults, and their complementary hunting techniques, led to this "limited, two-species social system."

The Invisible Carnivore

There is good reason why science waited so many years to corroborate and explain an association that Native Americans, western settlers and early naturalists took for granted. Badgers are solitary, usually forage at night and snooze away daylight hours in dens. In other words, badgers are invisible most of the time, making them unpopular research subjects. But these days, determined scientists are unearthing many new details about the ecology of this four-legged backhoe and are even using it in a critical study of the hazards posed by a toxic Superfund site in Colorado.

Biologist Barbara Ver Steeg of the Illinois Natural History Survey has just completed a six-year study of badgers on Midwest farmlands for the state's department of conservation. Her work is pioneering; until now, most badger research has taken place in the West. One significant finding: Illinois badgers are land barons compared to their counterparts on the plains. Badgers on the plains, which have access to populous colonies of ground squirrels and prairie dogs, have small home ranges covering 1 to 3 square miles. In Illinois, where patches of undisturbed cover are scattered between corn and soybean fields, badgers have to roam far and wide to find enough food, so individual ranges are enormous, spanning 8 to 14 square miles.

The badger is a native of North American grasslands and deserts, and if you draw a line from Houston to Kansas City to Columbus to northern Michigan, you've roughly defined the eastern extent of its range. John Madson, a prairie poet who grew up in Iowa badger country, described the beast as being "put together funny - a bowlegged, pigeon-toed doormat that sweeps the ground with its trailing end." Funny-looking it may be, but the badger is put together perfectly for a job it does better than anything else: digging.

For starters, the badger's head is wedge-shaped for nosing into the holes of burrowing rodents ranging in size from deer mice to woodchucks, and a keen sense of smell tells it whether anyone is home. Thanks to thick fur and loose skin, a badger can turn around with amazing ease in a tight burrow. And a nictitating membrane protects its beady eyes from flying dirt.

Oh does the dirt fly! Front claws up to 2 inches long loosen the soil, while short, shovel-like hind claws push it out of the burrow. "At high speeds," says Ver Steeg, "a tunneling badger throws a plume of dirt into the air behind it." A human wielding a shovel, she notes, is no match for this powerfully built, 15-pound carnivore.