Gray Wolf

The Gray Wolf (Canis lupus; also spelled Grey Wolf, Timber Wolf, Wolf) is a mammal in the order Carnivora. The Gray Wolf shares a common ancestry with the domestic dog (Canis lupus familiaris), and is known from DNA sequencing and genetic drift studies to be the progenitor of all dogs as they exist today. Gray wolves were once abundant and distributed over much of North America, Eurasia, and the Middle East. Today, for a variety of human-related reasons including widespread habitat destruction and excessive hunting, wolves inhabit only a very limited portion of their former range.

Gray wolves, being keystone predators, are integral components of the ecosystems to which they typically belong. The wide range of habitats in which wolves can thrive reflects their adaptability as a species, and includes temperate forests, mountains, tundra, taiga, and grasslands. In the contiguous U.S., with the exception of Minnesota and Wisconsin (where they have a threatened status), they are listed as endangered under the Endangered Species Act of 1973. They continue to be hunted in many areas of the world as perceived threats to livestock, humans and their well-being, as well as for sport.

Wolf weight and size can vary greatly worldwide, though both tend to increase proportionally with higher latitudes. Generally speaking, height varies from 0.6 to 0.9 meters (24 to 35 inches) at the shoulder, and weight can range anywhere from 25 to 65 kg (55-143 pounds), making wolves the largest among all wild canids. Although rarely encountered, extreme specimens reaching 80 kg (176 lb.) have been recorded in Alaska and Canada, though some people claim to have seen even larger anomalous individuals (90+ kg) roaming the Yukon, where some of the largest wolves in North America can be found. Customarily, however, wolves will be of a more typical physical capacity, with the females in a given population weighing about twenty percent less than their male counterparts. Wolves can measure anywhere between 1.3 and 2 meters (51 to 78 inches) from nose to tail tip, with the tail itself consisting of approximately one quarter of overall body length.

Wolves are built for stamina, possessing features tailored for long-distance travel. Narrow chests and powerful backs and legs contribute to the wolf's proficiency for efficient locomotion. They are capable of covering several miles trotting at about a 10 km/h (6 mph) pace, though they have been known to reach speeds approaching 65 km/h (40 mph) during a chase (wolves only run fast when testing potential prey). While sprinting thus, wolves can cover up to 5 m (16 ft) per bound.

A wolf sometimes seems more massive than it actually is due to its bulky coat, which is made of two layers. The first layer consists of tough guard hairs designed to repel water and dirt. The second is a dense, water-resistant undercoat that insulates. Wolves have distinct winter and summer pelages that alternate in spring and autumn. Females tend to keep their winter coats further into the spring than males.

Coloration varies greatly, and runs from gray to gray-brown, all the way through the canine spectrum of white, red, brown, and black. These colors tend to mix in many populations to form predominantly blended individuals, though it is certainly not uncommon for an individual or an entire population to be entirely one color (usually all black or all white). A multicolor coat characteristically lacks any clear pattern other than it tends to be lighter on the animal's underside. Fur color sometimes corresponds with a given wolf population's environment; for example, all-white wolves are much more common in areas with perennial snow cover.[4] Aging wolves acquire a grayish tint in their coats.

At birth, wolf pups tend to have darker fur and blue eyes that will change to a yellow-gold or orange color when the pups are 8-16 weeks old. Though extremely unusual, it is possible for an adult wolf to retain its blue-colored eyes. Wolves have stout, blocky muzzles that help distinguish them from coyotes and dogs. Wolves also differ in certain skull dimensions, having a smaller orbital angle, for example, than dogs (>53 degrees for dogs compared to less than 45 degrees for wolves) while possessing a comparatively larger brain capacity. Larger paw size, yellow eyes, longer legs, and bigger teeth further distinguish adult wolves from other canids, particularly dogs. Also, precaudal glands at the base of the tail are present in wolves, whereas they are not in dogs.

During the winter, moose may form loose aggregations in fairly dense conifer forests, which they keep open by trampling the snow. In the spring, moose can often be seen in drainage ditches at the side of roads, taking advantage of road salt which has run off the road. These minerals replace electrolytes missing from their winter diet.

During the mating season, breeding wolves become extremely affectionate with one another in anticipation for the female's ovulation cycle. Overall, pack tension rises, as each mature wolf begins to feel the urge to mate. In fact, during this time, the alpha male and alpha female may be forced to aggressively prevent other wolves from mating with each other. Under normal circumstances, a pack can only support one litter per year, so this type of dominance behavior is beneficial in the long run.

Normally, only the alpha pair of the pack breeds, which is a kind of organization not uncommon to other pack-hunting canids including the Dhole and the African Hunting Dog. Mating occurs between January and April, happening later in the year as latitude increases. A pack usually produces a single litter, though sometimes multiple litters will be born if the alpha male mates with one or more subordinate females. Under normal circumstances, the alpha female will try to prevent this by aggressively dominating other females and physically separating them from the alpha male during the mating season.

Wolves howl for several reasons. Howling helps pack members keep in touch, allowing them to effectively communicate in thickly forested areas or over great distances. Furthermore, howling helps to summon pack members to a specific location.[8] Howling can also serve as a declaration of territory, as portrayed by a dominant wolf's tendency to respond to a human imitation of a "rival" individual in an area that the wolf considers its own. This behavior is also stimulated when a pack has something to protect, such as a fresh kill. Wolves will also howl for communal reasons. Some scientists speculate that such group sessions strengthen the wolves' social bonds and camaraderie-similar to community singing among humans. During such choral sessions, wolves will howl at different tones and varying pitches, which tends to prevent a listener from accurately estimating the number of wolves involved. Observations of wolf packs suggest that howling occurs most often during the twilight hours, preceding the adults' departure to the hunt and following their return. Studies also show that wolves howl more frequently during the breeding season and subsequent rearing process. The pups themselves begin howling towards the end of July, and can be provoked into howling sessions relatively easily over the following two months. Such indiscriminate howling usually has a communicative intent, and has no adverse consequences so early in a wolf's life. Howling becomes less indiscriminate as wolves learn to distinguish howling pack members from rival wolves.

The relationship between humans and wolves has had a very long and turbulent history. Traditionally, humans have viewed wolves negatively, perceiving them to be dangerous or as nuisances to be destroyed. European folklore exacerbated this negative image, which was brought over to North America as it was settled. In brief, the gray wolf, which, at one point, could be found in any ecosystem on every continent in the Northern Hemisphere, was persistently one of the first species to go once a significant population of humans settled in a given area. As technology made the killing of wolves and other predators easier, simple control became something more like complete annihilation.

While progress has been made, traditional opinions prove difficult to change in some cases. Today and in the past, improved understanding and education have been the main allies in altering perceptions. As research improves and as people figure out better ways to educate people about the true nature of this planet's ecosystems, public acceptance of the wolf as an integral member of the earth's biological society will likely prevail.