Wood Bison

The Wood Bison is the Largest living, native terrestrial North American Mammal.

In March 2011, the first wood bison roamed free on American soil again for the first time in over 100 years. These animals that are the largest North American mammal, weigh about 350 pounds more than the plains bison. Wood bison live in grass and sedge meadows across British Columbia, Alberta, Manitoba, the Yukon, and Northwest Territories. A herd has been reestablished on Alaska’s Inoko Flats along the lower Yukon River. These animals are greatly affected by cold weather and significant snowfalls, which makes grazing extremely difficult.

5 Incredible Wood Bison Facts!

• Wood bison are the largest native terrestrial land mammal in North America.
• Wood bison may all come from 11 animals that survived in Canada.
• A wood bison calf is red when it is born.
• Wood bison have a distinctive upward hump at the base of their necks.
• Wood bison form herds by sex.

Wood Bison Scientific Name

The scientific name of the wood bison is Bison bison athabascae. That is different than the plains bison that is called the Bison bison bison. There is an excellent chance that both subspecies are descended from the Bison priscus, called the steppe bison. Furthermore, around 1920 when the Canadian government moved large herds of woods and plains bison to Wood Bison National Park, the two subspecies may have interbred dramatically.

Buffalo and bison are only distantly related, even though the terms are often used interchangeably. Buffalo live in Asia and Africa while bison live in North America and Europe. Buffalo does not have humps.

Wood Bison Appearance

The wood bison is the larger of the two bison species that live in North America. This species stands about 6-feet tall and is about 10-feet long. Males weigh about 2,000 pounds when mature while females weigh about 1,200 pounds.

Wood bison have a hairy coat that gets longer in the winter. They also have longer hair on their chins, resembling a beard. These adaptations help the wood bison stay warmer in the winter.

They are much wider in the front quarter than in the back quarter. This is one of the adaptations that help the animal use its front legs to remove snow easier to get to the grass under it. They have a large hump starting at the base of their necks and sloping downward through the front quarter. This adaptation helps them move their massive head through the snow in the wintertime to graze. The head has large horns that grow straight upward.

Mature wood bison have dark-brown-to-black hair along their legs and lower body. The hair is a lighter color over the rest of their bodies, including the hump. Calves are born with red hair that turns darker as they age. Red hair is one of the adaptations that help calves blend in better to their environment before they are old enough to defend themselves.

These bison has a short tail that is usually about 3-feet long. The tail ends in strands of dark hair.

What is the Difference Between a Wood Bison and a Plains Bison?

There are many differences between a wood bison and a plains bison. The plains bison is a smaller animal. It is about 250 pounds lighter. While male wood bison stand almost 7-feet tall at their withers, male plain bison stand about a foot shorter. Additionally, wood bison grow to be about 10 feet long while plains bison is about a foot shorter. Not only is the plains bison smaller than the wood bison, but it also has a stockier appearance.

Another difference between a wood bison and a plains bison is the head. The plains bison has a rounder head with fuzzy hair on it. By comparison, the woods bison has a more pointed head with long, straight hair draping down its forehead.

Yet, another difference between the two subspecies is that the woods bison’s hump is more pointed than the plain’s bison. Furthermore, when you look at the two species from the front, you will see long strands of hair on the plain’s front legs that are missing or much less prominent on the wood bison.

When examined from the side, the cape on the plain’s bison looks like an addition to its body, similar to a little child wearing a Superman cape. Meanwhile, on the woods bison, the cape looks like part of the natural hair process. The woods bison is also a darker color than the plains bison.

Wood Bison Behavior

Females and their calves live in groups of up to 60 animals throughout the year. Bulls live in smaller herds. Bison are opportunity eaters who will cover a large territory in search of food. When the food is gone from one area, they roam to another one to find ample food. Herd size often goes up or down depending on the availability of food.

Wood Bison Habitat

Most of these bison live in captive herds. There is one captive herd in Alaska, one in Sakha Republic, Russia, and the rest are in Canada. The Canadian government considers the herds living in its country to be wild animals. The government, however, has placed restrictions on where these animals can live, so 97.4% of their original habitat is not available to them.

One herd is near Aishihik Lake, Canada. Conservation efforts in this region of the Yukon are underway to return the habitat to its original arboreal forest state.

Another herd is along the Alaska Highway Corridor near the Aline Lake area east of Liard Hotsprings in northern British Columbia. This herd tends to move along the highway while grazing on the grass along the highways’ edges.

Another herd location is near Nahanni Butte in Southwestern Northwest Territory, Canada. This is an extremely isolated area, and this herd has more water access than many of the other herds. Therefore, researchers do not believe that it moves as often or as far as many of the other herds.

A final herd was established in Canada along the Etthithun River in northeastern British Columbia. This herd has about 5,000 square acres that it moves across regularly.

Wood Bison Diet

These bison are herbivores who dine on a variety of plant life throughout the year. In the winter, about 97% of their diet is sedges. In the spring and summer months, they eat sedges and willows. The bison include lichens in their autumn diet.

Overall, these bison prefer to live in moist sedge meadows during the winter months because it is easier to secure food there. They will use their large heads and neck muscles to move snow to get tasty things to eat. During the summer months, mountain bison often move to willow savannas, where the plants provide a higher amount of crude protein. In the fall, they often live in more wooded areas where lichen is regularly available.

Especially during extremely harsh winters, it is not unusual for up to 20% of mountain bison to starve to death.

Wood Bison Predators and Threats

Man is the largest threat faced by these bison. Canada still has laws in place allowing animals who are considered nuisances to be killed.

Additionally, the proximity of the bison to domestic cattle has allowed some cattle diseases to be passed into herds. In particular, anthrax was responsible for several mountain bison deaths in Wood Bison National Park and other Northern Canada locations. In about 1963, the government killed almost 600 healthy bison to prevent the spread of the disease further, and you can still see ramifications of that act in the present herd.

Wood Bison Reproduction and Life Cycle

Most mating in these bison occurs between July and September. The female gives birth about nine months later. Calves can walk from about the time that they are born.

While females become sexually mature at about 12 months, they often wait until after 18 months to breed. Then, they give birth to one calf every 1-to-3 years. Bulls mature a little slower and often do not reach sexual maturity until they are about 24 months old. They usually do not have a chance to breed until they are about 8 years old because they must wait for stronger and older bison to die or become injured.

These bison are polygamous, with each bull often impregnating numerous cows. Often during the breeding season, a mature bull will protect young cows until they are ready to breed. Then, he will impregnate them.

Wood Bison Population

There are about 4,400 of these bison left in the world. The majority of them live in herds in Canada.

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2. Discover, Available here: https://www.discovermagazine.com/planet-earth/wood-bison-roam-the-us-for-first-time-in-a-century
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