Wolf

Wolf

Carnivore related to the jackal and domestic dog. All wolves are characterized by powerful teeth, bushy tails, and round pupils. Certain characteristics of the skull distinguish them from domestic dogs, some breeds of which they otherwise resemble. Two species of wolves are recognized: the gray, or timber, wolf, once widely distributed in North America, Europe, and Asia; and the red wolf, which now occurs only in Texas and the southeastern United States. An adult gray wolf measures up to 1.6 m (6.5 ft) in length, including the tail (which is less than half the body length), and may weigh up to 80 kg (175 lb). The animal is red-yellow or yellow-gray, with black patches above and white below; black or brown timber wolves also occur, and those in the far north may be pure white. The red wolf is somewhat smaller in size and usually darker in color. Wolves are equally at home on prairies, in forestlands, and on all but the highest mountains. In the winter they travel in packs in search of food. Small animals and birds are the common prey of wolves, but a pack may sometimes attack reindeer, sheep, and other large mammals, usually selecting weak, old, or very young animals for easier capture. When no live prey can be found, wolves feed on carrion. They also eat berries. The den, or lair, of the wolf may be a cave, a hollow tree trunk, a thicket, or a hole in the ground dug by the wolf. In the spring, females have litters of one to eleven pups. Adult wolves sometimes feed young pups by regurgitating partly digested food for them. The pups normally stay with the parents until the following winter but may remain much longer. Parents and young constitute a basic pack, which establishes and defends a territory marked by urine and feces. Larger packs may also assemble, particularly in the winter; the pack leader is called the alpha male, and his mate is the alpha female. As social animals, wolves exhibit behavioral patterns that clearly communicate dominance over or submission to one another. The communal howling of a pack may serve to assemble its members, communicate with other packs, or advertise its territorial claims, or it may be simply a source of pleasure. Visual and scent signals are also important in communication. Although wolves are still abundant in eastern Europe and in Asia, only remnant populations now exist in western Europe, and their numbers in the Americas also have been greatly diminished. They are fairly abundant in Alaska and Canada, but significant remnant populations of wolves south of Canada occur only in Minnesota and Mexico; smaller numbers exist in several western and midwestern states. Under the Endangered Species Act, the gray wolf is listed as a threatened species in Minnesota and as an endangered species elsewhere in the United States outside of Alaska. The decreasing numbers of wolves are the result of encroachments on their territory by humans, who have long regarded wolves as competitors for prey and as dangerous to livestock, pets, and people. However, few, if any, healthy wolves have attacked humans, whom they instead try to avoid. Wolves are valuable predators in the food web, and their decimation has led to the overpopulation of certain other animal species in various areas. There are active efforts to reintroduce wolves to national parks in the United States, although such efforts are controversial. Coyotes have hybridized with some red wolves. An attempt to reintroduce red wolves to parts of North Carolina has involved identifying red wolves that were not part coyote; the success of this project is not yet clear. In 1995 and 1996, the United States Fish and Wildlife Service reintroduced Canadian gray wolves into Yellowstone National Park despite protest from ranchers and some biologists. The reintroduced wolves are producing more offspring than expected. When ten breeding pairs reside in the region for three years, the gray wolf will be taken off the list of endangered species in the northern Rocky Mountains. Wolf biologists estimate that this goal may be met by the year 2002 without the transplanting of additional wolves from Canada. Scientific classification: The wolf belongs to the family Canidae. The gray, or timber, wolf is classified as Canis lupus. The red wolf is classified as Canis rufus.