Wolves are legendary because of their spine-tingling howl, which they use to communicate. A lone wolf howls to attract the attention of his pack, while communal howls may send territorial messages from one pack to another. Some howls are confrontational. Much like barking domestic dogs, wolves may simply begin howling because a nearby wolf has already begun.
Wolves are the largest members of the dog family. Adaptable gray wolves are by far the most common and were once found all over the Northern Hemisphere. But wolves and humans have a long adversarial history. Though they almost never attack humans, wolves are considered one of the animal world's most fearsome natural villains. They do attack domestic animals, and countless wolves have been shot, trapped, and poisoned because of this tendency.
In the lower 48 states, gray wolves were hunted to near extinction, though some populations survived and others have since been reintroduced. Few gray wolves survive in Europe, though many live in Alaska, Canada, and Asia.
Red wolves live in the southeastern United States, where they are endangered. These animals actually became extinct in the wild in 1980. Scientists established a breeding program with a small number of captive red wolves and have reintroduced the animal to North Carolina. Today, perhaps 100 red wolves survive in the wild.
Despite their common name, gray wolves are not always just gray. These canids can also be black or white and the color of their coat is regulated by a complex set of genetic factors.
The frequencies of the various coat shades and colors that prevail within a wolf population often vary depending on the type of habitat the wolves occupy. For example, wolf packs that live in open tundra habitat consist of primarily light-colored individuals.
Such light colored coats enable the wolves that carry them to blend in with their surroundings and, in turn, conceal themselves when pursuing caribou, their primary prey. Wolf packs that living in boreal forests contain higher numbers of dark-colored individuals, as their habitat enables the darker colored individuals to blend in.
Of all the wolves' color variations, the black individuals are the most intriguing. Black wolves are so colored due to a genetic mutation at the K locus gene. This mutation causes a condition known as melanism, an increased presence of dark pigmentation which causes an individual to be black (or nearly black).
Black wolves are also intriguing because of their distribution. There are significantly more black wolves in North America than there are in Europe.
Because melanism is far more prevalent in North American wolf populations than it is in European wolf populations, it suggests that the cross between domestic dogs populations (rich in melanistic forms) likely occurred in North America.
Wolves live and hunt in packs of around six to ten animals. They are known to roam large distances, perhaps 12 miles (20 kilometers) in a single day. These social animals cooperate on their preferred prey—large animals such as deer, elk, and moose. When they are successful, wolves do not eat in moderation. A single animal can consume 20 pounds (9 kilograms) of meat at a sitting. Wolves also eat smaller mammals, birds, fish, lizards, snakes, and fruit.
Wolfpacks are established according to a strict hierarchy, with a dominant male at the top and his mate not far behind. Usually this male and female are the only animals of the pack to breed. All of a pack's adults help to care for young pups by bringing them food and watching them while others hunt.