Grey wolf
Canis lupus

Grey wolves had the largest natural distribution of any mammal except human beings. Sadly, they can no longer claim this record as they have been lost from much of their former range.

Subspecies
There are several subspecies of the grey wolf, including the timber wolf, the Rocky Mountain wolf, the Arctic wolf, the Mexican wolf, the Japanese and the Indian wolf.

Life span
In the wild, wolves tend to live for less than 10 years. In captivity, they can live for up to 20 years.

Statistics
Body length: 100-160cm, Tail length: 30-50cm, Standing height: 50-100cm, Weight: 15-80kg.

Physical description
The grey wolf is primarily grey or brown, but can range in colour from white to black. The belly and throat are lighter, and the legs, snout and ears are light brown to cinnamon. The male is usually 20 per cent bigger than the female.

Distribution
Wolves were once widely distributed across much of Eurasia from the Arctic to the Mediterranean, and in North America, their distribution extended from the far north to the Sierra Madre in Mexico.
Today the grey wolf can only be found in Canada, Upper Peninsula of Michigan and Wisconsin in the USA, Russia, and pockets of East Europe.

Habitat
Grey wolves are very adaptable to different terrain. They live in tundra, steppe, open woodland and forest.

Diet
They feed on large ungulates, beaver, small mammals, domesticated animals and rubbish.

Behaviour
Grey wolves live in a pack numbering anywhere from two to twenty members. Usually made up of wolves who are related to each other, the pack is a very tightly knit, highly organised group, travelling, hunting and raising pups together.

The pack follows a strict hierarchy to help maintain order. The alpha wolf (the leader), is usually female and rules the rest of the pack.

Reproduction
Wolves mate at the end of winter, and the pups are born after a gestation period of nine weeks. They are born in litters of between two and 10 pups. Once the pups leave the den, they are looked after by the entire pack, and so will bond with the other wolves.

Conservation status
Grey wolves have been eradicated in Western Europe, except in small populations in 10 countries. They have suffered from direct human persecution, long term habitat disturbance and diseases spread by domestic dogs. The Spanish/Portuguese sub-population is classified as Lower Risk, and the Italian subpopulation is considered to be Vulnerable. The Mexican subpopulation is classified as Extinct in the Wild, after their numbers were reduced to only 10 in the 1990s.