The Gray Wolf (Canis lupus)

Wolf recovery in Wisconsin began in the late 1970s.

Gray wolves, also referred to as timber wolves, are the largest wild members of the dog family. Males are usually bigger than females. Wolves have many color variations but tend to be buff-colored tans grizzled with gray and black (although they can also be black or white). In winter, their fur becomes darker on the neck, shoulders and rump. Their ears are rounded and relatively short, and the muzzle is large and blocky. Wolves generally hold their tail straight out from the body or down. The tail is black tipped and longer than 18 inches.

Wolves can be distinguished by tracks and various physical features. A wolf, along other wild canids, usually places its hind foot in the track left by the front foot, whereas a dog’s front and hind foot tracks usually do not overlap each other.


Wolves are social animals, living in a family group or pack. A pack usually has six to 10 animals – a dominant (“alpha”) male and female (the breeding pair), pups from the previous year (yearlings) and the current year’s pups. Additional subordinate adults may join the pack upon occasion. The dominant pair is in charge of the pack, raising the young, selecting denning and rendezvous sites, capturing food and maintaining the territory.

A wolf pack’s territory may cover 20-120 square miles, about one tenth the size of an average Wisconsin county. Thus, wolves require a lot of space in which to live, a fact that often invites conflict with humans.

While neighboring wolf packs might share a common border, their territories seldom overlap by more than a mile. A wolf that trespasses in another pack’s territory risks being killed by that pack. It knows where its territory ends and another begins by smelling scent messages – urine and feces – left by other wolves. In addition, wolves announce their territory by howling. Howling also helps identify and reunite individuals that are scattered over their large territory.

How does a non-breeding wolf attain dominant, or breeding status? It can stay with its natal pack, bide its time and work its way up the dominance hierarchy. Or it can disperse, leaving the pack to find a mate and a vacant area in which to start its own pack. Both strategies involve risk. A bider may be out-competed by another wolf and never achieve dominance. Dispersers usually leave the pack in autumn or winter, during hunting and trapping season.

Dispersers must be alert to entering other wolf packs’ territories, and they must keep a constant vigil to avoid encounters with people, their major enemy. Dispersers have been known to travel great distances in a short time. One radio-collared Wisconsin wolf traveled 23 miles in one day. In ten months, one Minnesota wolf traveled 550 miles to Saskatchewan, Canada. A female wolf pup trapped in the eastern part of the Upper Peninsula of Michigan, died from a vehicle collision near Johnson Creek in Jefferson County, Wisconsin in March 2001, about 300 miles from her home territory.

Nobody knows why some wolves disperse and others don’t. Even siblings behave differently, as in the case of Carol and Big Al, radio-collared yearling sisters in one Wisconsin pack. Carol left the pack one December, returned in February, then dispersed 40 miles away. Big Al remained with the pack and probably became the pack’s dominant female when her mother was illegally shot.

In another case, two siblings dispersed from their pack, but did so at different times and in different directions. One left in September and moved 45 miles east and the other went 85 miles west in November


Timber wolves are carnivores feeding on other animals. A study in the early 1980s showed that the diet of Wisconsin wolves was comprised of 55 percent white-tailed deer, 16 percent beavers, 10 percent snowshoe hares and 19 percent mice, squirrels, muskrats and other small mammals. Deer comprise over 80 percent of the diet much of the year, but beaver become important in spring and fall. Beavers spend a lot of time on shore in the fall and spring, cutting trees for their food supply. Since beavers are easy to catch on land, wolves eat more of them in the fall and spring than during the rest of the year. In the winter, when beavers are in their lodges or moving safely beneath the ice, wolves rely on deer and hares. Wolves’ summer diet is more diverse, including a greater variety of small mammals.

Breeding biology

Wolves are sexually mature when two years old, but seldom breed until they are older. In each pack, the dominant male and female are usually the only ones to breed. They prevent subordinate adults from mating by physically harassing them. Thus, a pack generally produces only one litter each year, averaging five to six pups.

In Wisconsin, wolves breed in late winter (late January and February). The female delivers the pups two months later in the back chamber of a den that she digs. The den’s entrance tunnel is 6-12 feet long and 15-25 inches in diameter. Sometimes the female selects a hollow log, cave or abandoned beaver lodge instead of making a den.

At birth, wolf pups are deaf and blind, have dark fuzzy fur and weigh about 1 pound. They grow rapidly during the first three months, gaining about 3 pounds each week. Pups begin to see when two weeks old and can hear after three weeks. At this time, they become very active and playful.

When about six weeks old, the pups are weaned and the adults begin to bring them meat. Adults eat the meat at a kill site often miles away from the pups, then return and regurgitate the food for the pups to eat. The hungry pups jump and nip at the adults’ muzzles to stimulate regurgitation.

The pack abandons the den when the pups are six to eight weeks old. The female carries the pups in her mouth to the first of a series of rendezvous sites or nursery areas. These sites are the focus of the pack’s social activities for the summer months and are usually near water.

By August, the pups wander up to two to three miles from the rendezvous sites and use them less often. The pack abandons the sites in September or October and the pups, now almost full-grown, follow the adults.


Before Europeans settled North America, gray Gray inhabited areas from the southern swamps to the northern tundra, from coast to coast. They existed wherever there was an adequate food supply. However, people overharvested wolf prey species (e.g., elk, bison and deer), transformed wolf habitat into farms and towns and persistently killed wolves. As the continent was settled, wolves declined in numbers and became more restricted in range. Today, the majority of wolves in North America live in remote regions of Canada and Alaska. In the lower 48 states, wolves exist in forests and mountainous regions in Minnesota, Michigan, Wisconsin, Montana, Idaho, Wyoming, Washington, Arizona, New Mexico, North Dakota, and possibly in Oregon, Utah and South Dakota.

Map showing wolf distribution

History in Wisconsin

Before Wisconsin was settled in the 1830s, wolves lived throughout the state. Nobody knows how many wolves there were, but best estimates would be 3,000-5,000 animals. Explorers, trappers and settlers transformed Wisconsin’s native habitat into farmland, hunted elk and bison to extirpation, and reduced deer populations. As their prey species declined, wolves began to feed on easy-to-capture livestock. As might be expected, this was unpopular among farmers. In response to pressure from farmers, the Wisconsin Legislature passed a state bounty in 1865, offering $5 for every wolf killed. By 1900, no timber wolves existed in the southern two-thirds of the state.

At that time, sport hunting of deer was becoming an economic boost to Wisconsin. To help preserve the dwindling deer population for this purpose, the state supported the elimination of predators like wolves. The wolf bounty was increased to $20 for adults and $10 for pups. The state bounty on wolves persisted until 1957. By the time bounties were lifted, millions of taxpayers’ dollars had been spent to kill Wisconsin’s wolves, and few wolves were left. By 1960, wolves were declared extirpated from Wisconsin. Ironically, studies have shown that wolves have minimal negative impact on deer populations, since they feed primarily on weak, sick, or disabled individuals.

The story was similar throughout the United States. By 1960, few wolves remained in the lower 48 states (only 350-500 in Minnesota and about 20 on Isle Royale in Michigan). In 1974, however, the value of timber wolves was recognized on the federal level and they were given protection under the Endangered Species Act [exit DNR]. With protection, the Minnesota wolf population in-creased and several individuals dispersed into northern Wisconsin in the mid-1970s. In 1975, the Wisconsin Department of Natural Resources declared timber wolves endangered.

Intense monitoring of wolves in Wisconsin by the DNR began in 1979. Attempts were made to capture, attach radio collars and radio-track wolves from most packs in the state. Additional surveys were done by snow-tracking wolf packs in the winter and by howl surveys in the summer. In 1980, 25 wolves in 5 packs occurred in the state, but dropped to 14 in 1985 when parvovirus reduced pup survival and killed adults. Wisconsin DNR completed a wolf recovery plan in 1989. The recovery plan set a state goal for reclassifying wolves as threatened once the population remained at or above 80 for three years. Recovery efforts were based on education, legal protection, habitat protection, and providing compensation for problem wolves.

In the 1990s the wolf population grew rapidly, despite an outbreak of mange between 1992 -1995. The DNR completed a new management plan in 1999. This management plan set a delisting goal of 250 wolves in late winter outside of Indian reservations, and a management goal of 350 wolves outside of Indian reservations. In 1999, wolves were reclassified to state threatened status with 205 wolves in the state. In 2004 wolves were removed from the state threatened species list and were reclassified as a protected wild animal with 373 wolves in the state.

Current status

After five years of delisting attempts and subsequent court challenges, a new federal delisting process began on May 5, 2011 and wolves were officially delisted on January 27, 2012. The count in winter 2011 was about 782-824 wolves with 202-203 packs, 19-plus loners, and 31 wolves on Indian reservations in the state. A federal court decision relisted the gray wolf as endangered in December 2014.

From Source: Wisconsin DNR website.

photograph credit Wisconsin DNR.

One Reply to “The Gray Wolf (Canis lupus)”

  1. Thank you very much for the historical and background nformation on the wolves in the Wisconsin and Minnesota. Very well written and informative!

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