Wolves are extreemly expressive, and make use of a wide repertoire of growls, barks, whines, and squeals to communicate. By far the most famous method of communication, however, is the howl - which may have more power to stir human emotions than any other animal cry. Wolves howl for any number of reasons. They may wish to attract a mate, or bring the pack together, or even inform members of their own pack ( or others ) of their whereabouts. They may howl before a hunt, after consuming a kill, or when an intruder is present. Wolf pups may howl in distress or after they have been playing. Experienced observers note that there are different types of howls for different occasions - hunting, communication within the pack, even mourning. Howls range in duration from one to ten seconds. Across open territory, a wolf howl can be audible for ten miles. Such communal howls confuses listeners into believing they hear many more wolves than are actually howling. General Ulysses S. Grant wrote in his memoirs of hearing twenty wolves howl at a distance. In fact, there were only two.
Another form of communication among wolves is scent marking. Wether it be by urination, scratching, or defecation. Scratching, which is often done after urinating, appears to release oders from scent glands in the wolf's paws. Thus it leaves both a scent mark and a visual sign of the wolf's presence. Wolves use scent marking to delineate territorial boundries between packs, so that a series of scent marks serves as a warning to other wolves to keep away. Biologists have noted that wolves usually leave more scent marks around the perimeter of their established territory than in it's center. Scent marks may also be used as a kind of road map to enable wolves to find their way.
Wolves also possess highly developed senses of hearing and smell. Observers of these creatures have long noted their keen ability to detect the scent of prey, and scientist have estimated the wolf's sensitivity to smells at one hundred times that of a human beings. One writer observed that a pack of wolves detected a moose and it's calves from a distance of several miles. Hearing in these animals is equally impressive. Wolves have been known to answer human beings imitating wolf howls from 3 miles away, and one researcher estimates that they can detect sound at two or three times that distance. As with many large mammals, the wolf's sense of site is less keen, but because they have a high proportion of rods ( faint light receptors ) to cones ( color receptors ) in the retina, their night vision is very good, and conciderably superior to that of a human being.
The life of a wolf in the wild is not easy. Diseases like distemper, tapeworm, and heartworm. Injuries from the hooves and horns of intended prey. Shortages of food and the ravages of winter all take their toll. But the wolf's greatest enemy inflicts by far the greatest damage: MAN. Hunting, poisoning, trapping and highway deaths have been responsible for a massive decline in the wolf population. Scientists determine a wolf's age by analyzing the teeth, and wild wolves rarely live longer than five or six years. Captive ones, by contrast, may last three times as long. The oldest captive wolf died at age seventeen.
Packs, the basic social structure in the wolf's existence, consist of extended families of wolves, and range in size from three to twenty-five, most number five to eight wolves. Every pack develops it's own unique personality that differentiates it from the others. Observers familiar with certain packs can identify them from a distance by the wolves behavior alone. Some packs may last a relatively short time, breaking up in the summer or winter. Others remain together for years, inhabiting the same dens, hunting the same territory, and maintaining certain behavior patterns, even after the founding members have left or died.
The wolf's breeding period generally extends from February to March. While often only one female in the pack becomes pregnant ( usually the Alpha, or dominate female ) sometimes two or more females in the pack will breed. The expectant female finds or constructs a suitable den, usually by digging into hillsides or under large tree trunks or boulders. Sometimes naturally occurring caves are used as well. Wolves keep their dens extremely clean and the mother or father often remains on guard outside. The female gives birth in April, usually to four to six pups, although the litter size will depend on the availability of game and the density of the other wolves in the territory. The fewer the wolves, the larger the litters. During famines or other times of severe environmental stress, a pack may not breed at all. This probably increases it's chances of survival. The pups are deaf and blind at birth. They can hear after a few days, and see after about two weeks, and make their first howls ( which often startle them ) after one month. They are weaned at five weeks, when they begin frisking at the dens enterance. By eight weeks, pups are playing with one another, licking, chewing, and climbing over adult pack members, and huddling close to them when they lie down. Chances of survival for wolf pups are less than fifty pecent, because packs often have difficulty finding enough food to keep all the pups healthy. Distemper and other diseases kill some, while eagles, lynx, and bears are also known to prey on wolf pups. Survivors grow quickly, approaching their full adult weight at around eight months.
The North American gray wolf is a formidable physical presence. It can grow to almost five feet in length, not including the tail, and stands two to three feet at the shoulder. A thick, fluffy coat makes it appear even larger than it actually is. Many people who have observed wolves in the wild, infact, are surprised to discover how relatively light they are. Weights range from 40 to 175 pounds, but average 60 to 100 pounds. In general, larger wolves tend to come from more northernly regions. Wolves resemble large dogs, but with longer legs are far bigger feet. They have broad faces, yellow eyes, and thick coats with an outer layer of long, moisture-repelling gaurd hairs and dense light-colored under-fur beneath. The coloring varies widely, though most have a brownish-gray coat. White wolves are most common in the far north. The wolf is built for running. It's chest is narrower than a dogs of a similar size, which enables it to push through thick winter snows more easily. Huge feet, ( the paw print is equal to or larger than a mans hand ) help it to stay on top of deep snows while tracking game. Wolves spend a temendous amount of time on the move ( eight to ten hours a day on average ) usually during the twilight hours. A naturalist in Alaska once saw a pack cover forty miles in a daily round of hunting. Artic wolves, a subspecies of the gray wolf, may pursue a caribou for five or six miles at a steady run before launching their attack. The wolfs jaw and teeth are superbly suited to predation, and forty-two teeth have evolved to fulfill special functions. The long canines can seize and hold meat or bones, the sharp incisors can slice off the tail of a buffalo cleanly. The premolars and molars at the back of the mouth can exert enormous crushing pressure and crack open bones so that the wolf can eat the nutritious marrow inside.