The smallest breed of wolves is the 70 pound 32 inches tall red wolf. These wolves are endangered because people destroy forests which is where they live and they build on their territory. Some red wolves are mating with coyotes. Only 300 live in the world today, about 80 of them are in the wild.
These wolves are the most common and also the largest breed of wolves, an average Grey wolf weighs 100-175 pounds. They can be found in the Northern Hemisphere in places like Alaska, Canada, and the region around the Great Lakes. Thirty gray wolves from Canada have been reintroduced into Yellowstone National Park. Grey wolves are important to the food chain because they keep the number of caribou and other hoofed animals down so the herds won't get too large. If the herds get too big there won't be enough food for everyone in the herd and there will be problems. Another reason the wolves are important is because they also hunt the sick animals so the disease won't make other animals sick.
The Arctic wolf is the purest of all wolf breeds. They are a Grey wolf sub-species and often have up to 30 members in a pack. When they have pups they normally have 7-10. Arctic wolves have white fur that blends with snow well. These wolves live in Canada, and hunt musk oxen, arctic hare, and lemmings.