Eastern Timber Wolf

(Canis lupus lycaon)

By Richard P. Thiel and Adrian P. Wydeven

Edited by Anne Hallowell

Table of Contents


Few people have ever heard the sound of a howling timber wolf. Only a small number of wolves now live in Wisconsin, one of just seven states in the country where wolves exist in the wild.

Timber wolves, also called gray wolves, are the largest wild members of the dog family. Males are usually bigger than females. Timber wolves have silvery gray-brown backs, light tan underparts, and bushy tails. In winter, their fur becomes darker on the neck, shoulders, and rump.

How can you tell the difference between a timber wolf and a coyote or a large dog? Size is a key difference between coyotes and wolves. A coyote is only half as big as a wolf. Distinguishing between a large dog and a wolf can be more difficult. Dogs and wolves can be identified by their tracks, though doing this is hard and takes a lot of practice. A wolf usually places its hind foot in the track left by the front foot, whereas a dog's front and hind foot tracks do not overlap each other. As well, dogs tend to "zig-zag" as they walk, while wolves and coyotes usually walk in a straight line.


Wolves are social animals, living in a family group, or pack. A pack usually has six to ten 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 heirarchy. 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, 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 shot in Ontario in November 1989 had traveled over 300 miles from its original home in Lincoln County, Wisconsin.

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 1980's showed that the diet of Wisconsin wolves was comprised of 55% white-tailed deer, 16% beavers, 10% snowshoe hares and 19% mice, squirrels, muskrats and other small mammals. Wolves' food habits change with seasonal shifts in the availability of prey species. For example, 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 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 (February-March). 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 or cave instead of making a den.

At birth, wolf pups are deaf and blind, have dark fuzzy fur and weigh about one pound. They grow rapidly during the first three months, gaining about three 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 of 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 wolves 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 small numbers and in only a few tracts of minimally disturbed northern forest in Minnesota, Michigan, Wisconsin, Montana, Idaho, and Washington.

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 deep 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 1973, however, the value of timber wolves was recognized on the federal level and they were given protection under the Endangered Species Act. With protection, the Minnesota wolf population increased and several individuals dispersed into northern Wisconsin in the mid-1970s. In 1975, the Wisconsin Department of Natural Resources declared timber wolves endangered. A wolf research program was initiated in 1979.

Studies since 1979 have shown that four to thirteen wolf packs, totaling 15-45 animals, roamed portions of northern Wisconsin. Wisconsin's wolf population is small but seems to be increasing. During recent years 15 of 25 radio-collared wolves that died were killed by humans. Average adult mortality was about 35% in the early 1980s, but has been reduced to 24% the last few years.

Canine parvovirus. a lethal canine disease, is one of several diseases that are a suspected cause of death among Wisconsin wolves. Other diseases include Canine Distemper, Lyme Disease, Mange, and various parasites such as Heartworm and Coccidiosis.

Current Status

The timber wolf is listed as an endangered species in Wisconsin by both the U.S. Fish and Wildlife Service (1973) and the Wisconsin Department of Natural Resources (1975). Fines and a possible prison sentence await anyone convicted of killing a wolf. About 40-45 wolves exist in Wisconsin in 1992 and the population is increasing.

Misconceptions and Controversies

Wolves are the "bad guys" of fable, myth, and folklore. The "big bad wolf" fears portrayed in Little Red Riding Hood, Peter and the Wolf, and other tales have their roots in the experiences and stories of medieval Europe. Wolves were portrayed as vile, demented, immoral beasts that often issued pacts with the Devil. During the Inquisition, people accused of "werewolfry" were executed. These subtle but powerful negative attitudes and misconceptions about wolves have persisted through time, perpetuated by stories, films and word-of-mouth, even when few Americans will ever have the opportunity to encounter a wolf.

Wolves are controversial because they are large predators. Farmers are concerned about wolves preying on their livestock. Since 1976, when wolves returned to northern Wisconsin, verified cases of wolf depredation occurred about every other year. As the population continues to increase, slight increases in depredation are likely to occur.

A few hunters continue to kill wolves, believing that such actions will help the deer herd. It is important to place in perspective the impact of wolves feeding on deer. Each wolf kills about 18 deer per year. Multiply this by the number of wolves found in Wisconsin in recent years (40), and approximately 720 deer may be consumed by wolves annually. This appears as a "drop in the bucket" when compared to over 30,000 deer hit by cars each year, and about 350,000 deer shot annually by gunhunters.

Research and Management

Wisconsin wolves are difficult to study because they live in remote, dense forests, avoid people and travel great distances. Biologists use radio telemetry to help them study wolves. Radio telemetry involves capturing a wolf using a trap, then tranquilizing it and placing a radio transmitter collar on it. While the wolf is tranquilized, researchers determine its sex, age, size and weight and take blood samples to help assess the wolf's health. By following wolves' movements via radio signals, scientists can begin to understand the animals' behaviors, life histories and many other aspects of wolf ecology. They can keep track of birth and death rates, causes of mortality and behavior patterns such as how often and far wolves travel. This information assists researchers and managers in assessing and helping to maintain wolf populations.

The Department of Natural Resources recognizes that wolves are a natural, valuable part of the Wisconsin ecosystem and possess the intrinsic right to exist. The Department approved a Wolf Recovery Plan in 1989. The Plan's goal is to attain a population of 80 wolves in 10 packs by 2000. Actions outlined in the Plan are designed to improve the wolf's chances for long-term survival. Strategies for accomplishing this include providing space for wolves separate from farming regions, continuing research, and designing community education programs that provide the public with opportunities to learn more about wolves and to assist in wolf recovery work.

What You Can Do

The future of wolves in Wisconsin is uncertain. While the Department of Natural Resources and many Wisconsin citizens are working hard to ensure the survival of Wisconsin wolves, the job is a big one and requires the cooperation and support of many people. Wolf Recovery Team members invite citizens to become informed about the history, role, and status of wolves in Wisconsin. They also welcome contributions to the Endangered Resources Fund on the Wisconsin Income Tax Form and encourage citizen action in support of wolf recovery.

Contributions by the Wisconsin Audubon Council, Wisconsin Wildlife Federation and Wisconsin taxpayers have helped make this publication possible. To contribute, or for further information, contact:

Bureau of Endangered Resources
P.O. Box 7921
Madison, WI 53707

Further Reading