American Bison
Kingdom
Phylum
Subphylum
Class
Order
Family
Subfamily
Tribe
Genus
SPECIES
Bison bison
Population size
11,248-13,12
Life Span
15-40 years
Top speed
35
22
km/hmph
km/h mph 
Weight
318-1000
699.6-2200
kglbs
kg lbs 
Height
152-186
59.8-73.2
cminch
cm inch 
Length
2-3.5
6.6-11.5
mft
m ft 

The American bison (Bison bison) is a species of bison native to North America. Sometimes colloquially referred to as buffalo (a distinct species of bovine), it is one of two extant species of bison, alongside the European bison. Once roaming in vast herds, the species nearly became extinct by a combination of commercial hunting and slaughter in the 19th century and introduction of bovine diseases from domestic cattle. With a population in excess of 60 million in the late 18th century, the species was culled down to just 541 animals by 1889. Through multiple reintroductions, American bison now freely roam wild in several regions in the United States, Canada, and Mexico, with them, also being introduced to Yakutia in Russia.

Di

Diurnal

He

Herbivore

Gr

Graminivore

Te

Terrestrial

Cu

Cursorial

Pr

Precocial

Gr

Grazing

No

Nomadic

Co

Congregatory

Vi

Viviparous

Po

Polygyny

Da

Dangerous

So

Social

He

Herding

Do

Dominance hierarchy

Mi

Migrating

A

starts with

Lu

Lucky Animals
(collection)

U.

U.S. States Animals
(collection)

Ca

Canada Province Animals
(collection)

Da

Dangerous Animals
(collection)

Appearance

The color of the American bison fur varies in the front and back of its body and is different shades of brown. Bison is hunchbacked and it has a long beard on its chin. The forehead is wide and narrow while the neck is short. Hind legs are smaller than front legs, making up a scarp from humpback to tail. Length of hair differs in front and rear, especially in males: front hair is significantly longer than rear hair. Horns of bison are black, bent inward withal upward, and pointed.

Video

Distribution

Geography

In the past, a huge number of bison thundered North America from Mexico to Alaska. Then, mass killings of these impressive animals led to their total extermination from the main area of their habitat. However, bison survived and currently they live primarily in Canada and the western part of the USA, usually in protected areas and national parks. American bison prefer to inhabit river valleys, prairies, and plains. Typical habitat is open or semiopen grasslands, as well as sagebrush, semiarid lands, and scrublands. Bison also graze in hilly or mountainous areas where the slopes are not steep.

American Bison habitat map

Climate zones

American Bison habitat map
American Bison
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Habits and Lifestyle

American bison is diurnal, being active all day long. They are usually relatively passive during the day, becoming particularly active at dusk and dawn. They spend a lot of time cleaning the fur or grooming: they rub their head, sides, and necks against trunks of trees. Bison are able to be constantly on the move, passing long distances as long as there is food. Cows, female bison, are leaders of family groups while males stay separate, creating small groups or living solitarily. As the mating season comes, males join female groups. Bison like rolling, weltering, and rubbing against the ground. Wallows are recesses - dust bowls with no vegetation, having circular form, formed as a result of bison’s wallowing on the ground.

Seasonal behavior

Diet and Nutrition

Bison are herbivores (graminivores) and, more specifically, grazers, chewing grass all year round. However, in absence of grass, they eat other greenery found in the area such as sagebrush. The presence of water is another important component of their life: they can’t last long without a source of water.

Mating Habits

MATING BEHAVIOR
REPRODUCTION SEASON
June-September
PREGNANCY DURATION
285 days
BABY CARRYING
1 calf
INDEPENDENT AGE
1 year
FEMALE NAME
cow
MALE NAME
bull
BABY NAME
calf

Bison are polygynous, meaning that a dominant male, or a bull, mates with a group of females. The season for breeding takes place in summer, from June to September while the gestation period lasts about 285 days. A female can give birth to a single calf each season. Newborn calf weight about 15-25 kg. To give birth, bison females choose shelter, a distant place far from the herd. Protection of the calf lies on the shoulders of females whereas males don’t take part in this process. Babies are breastfed for 7-8 months and weaned when they are one year old. Males reach sexual maturity at the age of 3 years and females - from 2 to 3 years.

Population

Population threats

The most notable threats to the population of this species as a whole are long-time persecution of bison from their habitat; slow growth of population in closed and protected areas; genetic manipulation for commercial purposes; hybridization and backcrossing of bison and other cattle as well as between different bison subspecies; natural limiting factors in conditions of reservations; and the possible threat of depopulations of bison because of its wild populations’ carrying cattle deceases; continuous culling of bison in order to preclude brucellosis and bovine tuberculosis infection.

Population number

According to the IUCN Red List resource, the total population size of the American bison is around 31,000 individuals in 68 conservation herds in North America. The total wild population of the species is estimated to be between 11,248 and 13,123 mature individuals in North America. Currently, the American bison is classified as Near Threatened (NT) on the IUCN Red List but its numbers today are stable.

Ecological niche

Bison was an important component of the flatlands ecosystem in its habitat. When grazing, the animal thrusts its hooves into the soil, thus fertilizing it. Plains, grazed by bison, were inhabited by prairie dogs, protecting them against predators due to being shorter and thus providing a better view of the surrounding area. Corpses of bison were a delicacy for scavengers while their meat was the main source of food for the local population of wolves and humans. Bison fertilized the plains of the habitat thus becoming predecessors of farmers.

Fun Facts for Kids

  • Dense coat of bison protects it from the rough elements of the American plains. In winter the coat becomes solid and even thicker, so that bison are seen with snow on their backs, not melting due to their coats isolating their warm skin from the outer surface.
  • The groups that bison create are called obstinacies, gangs, or herds.
  • Hunch on its back is nothing but a bunch of muscles. The hunch also helps bison to move into the snowpack.
  • Bison is an excellent jumper, able to jump up to 6 feet off the ground.
  • Bison have a heightened sense of hearing, being able to identify big objects from a 1 km distance and moving objects - at a distance of 2 km.
  • Along with jumping, bison are excellent at running and swimming.
  • Newborn calves start walking and running a few hours after being born.

Coloring Pages

References

1. American Bison Wikipedia article - https://en.wikipedia.org/wiki/American_bison
2. American Bison on The IUCN Red List site - http://www.iucnredlist.org/details/2815/0

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