Sunday, 1 May 2011

Report Text_Wolves_Glossopedia



Wolves

Howling Hunters

Wolves are a lot like dogs—big, wild dogs. Wolves are closely related to coyotes, jackals, foxes, and the dogs you see romping in your neighborhood park. Like dogs, wolves are social and even playful sometimes. Wolves are predators who live and hunt in packs. They are well known for their eerie howling and their intelligence. They plan their hunts and carefully coordinate their actions, which allow them to take down prey much bigger than themselves.

Wolves Around the World

Typically, “wolf” refers to one particular species — the gray (or timber) wolf of North America. Subspecies of the gray wolf include the tundra wolf (found in northern Europe and northern Asia) and the Mexican wolf. Other wolf species include red wolves, Indian wolves, Himalayan wolves, Eastern Canadian wolves, and Ethiopian wolves.
There was a time when wolves had the largest range of any (nonhuman) land mammal. They could be found over much of the Northern Hemisphere. In the mid-1930s, however, many wolves were killed in the United States. This greatly reduced their populations. Now they are an endangered species in most states. However, wolves can still be found in U.S. states such as Alaska, Michigan, Wisconsin, and Montana. They are also found in most of Canada, Eastern Europe, and much of northern Asia. Canada has the largest population of wolves—about 60,000. The worldwide wolf population is about 200,000.

The First Wolves

The evolution of wolves began about 30 million years ago with a small, doglike mammal called Cynodictus. Over the next several million years, one branch of Cynodictus’s descendents developed characteristics such as longer legs, larger brains, and the dewclaw we see on dogs and wolves today. Wolves haven’t changed their shape much in the last million years.

Sizing up Wolves

In all species, adult males and females are similar in appearance, but males are taller, longer, and heavier than females. The main differences among wolf species and subspecies are size and color. The largest species is the gray wolf. A gray wolf is about 90 cm tall, 190 cm from tail to nose, and weighs about 60 kg. The smallest wolves are Mexican wolves. They weigh just over half the weight of the largest gray wolves.

Very Adaptable Creatures

Wolves have proved to be highly adaptable to different environments. They were once found in the northern tundra, subtropical areas, and deserts. Today, most wolves live only in the most northern regions of the world. They have many adaptations common to animals that live where it is very cold, such as thick coats and relatively small ears.

Leaders of the Pack

Wolves live in groups called packs that usually consist of four to seven wolves. Each pack has a hierarchy. It is led by a mated pair, called the alpha male and alpha female. Within the pack, the alpha pair leads the hunts, chooses the dens, and may try to keep other pack members from breeding. (A pack can only take care of a limited number of pups every year.) In many cases, only the alpha pair breeds. Larger packs have not only alphas, but also betas, the second-in-command wolves.

A Six-Pack of Pups

Breeding usually occurs in January or February. After a pair of wolves breeds, it takes about 65 days for a litter of 6 babies (called pups) to be born. The newborn pups have soft, black fur. At three weeks, pups begin walking around and exploring. When they are a couple of months old, their fur starts to take on the coloring of adults: gray, black, yellowish-brown, or even all white.

Pups Grow Up Fast

For their first year, pups remain with the pack. The whole pack helps raise the pups. Older wolves help pups learn hunting and other skills. By the time pups are one year old, they are fully grown. Between one and two years of age, pups begin to stray from the pack. When they’re two, they leave the pack to find packs and territories of their own. Only about one pup from every litter lives long enough to go out on its own. Wolves in the wild typically live for 7 to 8 years.

Wolfing Down Food

Wolves are carnivores. They can eat huge quantities of meat at one meal—perhaps up to 20 percent of their body weight. If a full-grown man ate that much at one meal, he’d be eating more than 13 kg of food! Wolves’ favorite foods are large hoofed mammals such as deer, elk, bison, and moose. Wolves also will eat smaller prey, such as rodents, rabbits, and beavers.

Wolves Help Keep Ecosystems in Balance

Wolves are strong predators and are at the top of the food chain. The deer, elk, and moose that wolves prey upon are large herbivores. They eat huge quantities of plant matter, which can deprive smaller herbivores of food. But when wolf populations are large, wolves help keep the numbers of large herbivores down. This gives a wider range of plant-eating animals a better chance of surviving. In this way, wolves help keep the balance of their environment healthy. The bottom line: when wolves do well, ecosystems and biodiversity do well, too.

What Are They Howling About?

Wolves are skilled communicators. The most famous example of wolf communication is howling. Wolves howl in order to keep in touch with each other over long distances, to call pack members together, or to stake out a territory. Wolves might even howl together to strengthen group bonds—a sort of group sing-along.

Howling Isn’t Everything

Wolves also communicate with body language. They use their tails, faces, ears, and other body parts to get messages across to each other. If you’ve seen a dog tuck its tail between its legs, flatten its ears, or wag its tail, you’re already familiar with some of the ways wolves use their bodies to communicate. These actions are used to express a wide range of emotions and attitudes including submissiondominance, happiness, and fear. Wolves also use scents from droppings or urine as territory markers and landmarks.

Wolves and Other Predators

When wolves’ favorite prey is plentiful, packs combine or increase in size to create larger hunting parties. Wolves also travel farther. Depending on the amount of prey in an area, a pack’s territory can range from 130-2,600 km2.
Wolves will not put up with coyotes or cougars in their territory. Coyotes and cougars are a danger to wolf pups. To protect their young and their territory, wolves will attack and kill cougar cubs and even adult cougars. In some parts of the Middle East, wolves sometimes meet up with striped hyenas. Working together   as a pack, the wolves usually manage to defeat the hyenas. In parts of Russia, wolves face serious competition for prey from Siberian tigers.

Legendary Wolves

Some cultures have legends that speak of wolves in a positive light. According to one legend, the founders of Rome were nursed by a wolf. Various groups of Turkic peoples in central and northern Eurasia have honored the wolf as well. In fact, some say that the people are the descendents of a wolf. The story tells of a village in which all the people were killed, except for one little boy. He was rescued by a wolf. In time, the wolf gave birth to half wolf, half human children, who became the Turkic people.

An Undeserved Reputation

In many places, wolves are still often viewed with suspicion, fear, or hatred by their only predator—humans. In an effort to defend livestock such as cattle, people have often killed wolves. In most American states, wolves are nonexistent or very rare. Worldwide, however, wolves are not endangered.
The truth is that wolves prefer wild prey not livestock. And, in general, wolves are scared of humans. Wolves prefer to be at least .5 km away from any human. It’s true that wolves have attacked humans. But for the most part, they don’t want anything to do with us! In addition, as human populations spread into wolf territory, the wolves’ prey can decline in numbers, which means that wolves don’t have enough to eat.

Welcoming Wolves Back to Their Natural Habitat

Wolves have also benefited from human activities. Programs to reintroduce gray wolves to their natural habitats have been very successful. These efforts have helped the wolf populations bounce back in parts of the United States such as Yellowstone National Park and parts of Idaho. Conservationists were able to overcome the concerns of ranchers by promising them that they would be paid for any livestock that were killed by wolves. Mexican wolves have been reintroduced into Arizona and New Mexico. The United Kingdom is currently considering plans to reintroduce wolves, too.

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