The Wood Bison or Wood Buffalo^[1] (Bison bison athabascae) is a distinct northern subspecies of the North American Bison. Its original range included much of the boreal forest regions of Alaska, Yukon, western Northwest Territories, northeastern British Columbia, northern Alberta, and northwestern Saskatchewan. It is included on the Committee on the Status of Endangered Wildlife in Canada (COSEWIC) Threatened species list.

Morphology

The Wood Bison differs from the Plains Bison (Bison bison bison), the other surviving North American subspecies, in a number of important ways. Most notably, the Wood Bison is heavier, with large males weighing over 900 kilograms (approximately 2000 lbs), making it the largest terrestrial animal in North America. The highest point of the Wood Bison is well ahead of its front legs, while the Plains Bison's highest point is directly above the front legs.

Conservation

Reduced by hunting from a total population of about 168,000 to less than 250 individuals by the year 1900, the Wood Bison was believed to be extinct by about 1940.

A herd of about 200 was discovered in Alberta, Canada in 1957, and has since recovered to a total population of approximately 3,536, largely as a result of conservation efforts by Canadian government agencies. In 1988, the Committee on the Status of Endangered Wildlife in Canada (COSEWIC) changed the subspecies' conservation status from "endangered" to "threatened". A subsequent reevaluation by COSEWIC in 2000 confirmed the status of "threatened".

In the United States, small herds (n?15) of wood bison are also located in the Alaska Wildlife Conservation Center. It is a private non-profit facility about 45 minutes south of Anchorage, Alaska on the Seward Highway.

The wood bison can also be found in "Pleistocene Park", Siberia (n?30), as well as in several zoos and private game ranches.

Diseases

Publicly-owned free-ranging herds in Alberta, British Columbia, Yukon, and the Northwest Territories comprise 90% of existing Wood Bison, although six smaller public and private captive breeding herds with conservation objectives comprise approximately 10% of the total (n?900). These captive herds and two large isolated free-ranging herds in the Yukon and Northwest Territories all derive from disease-free and morphologically representative founding stock from northern Wood Buffalo National Park in northeastern Alberta and southern Northwest Territories. These captive herds are particularly important for conservation and recovery purposes, because the larger free-ranging herds in and around Wood Buffalo National Park were infected with bovine brucellosis and tuberculosis after 7,000 Plains Bison (Bison bison bison) were trans-shipped by barge from Buffalo National Park (Wainwright, Alberta) to Wood Buffalo National Park by the federal government during the 1920s.

This trans-shipment of Plains Bison also resulted in the hybridization of all known wood bison (i.e., there are no longer any "genetically pure" Wood Bison). Brucellosis and tuberculosis remain endemic in the free-ranging herds in and around Wood Buffalo National Park. The diseases represent a serious management issue for governments, various local Aboriginal groups, and the cattle industry (which is rapidly encroaching on the Park's boundaries). Disease management strategies and initiatives began in the 1950s, and have yet to result in a reduction of the incidence of either disease despite considerable expenditure and increased public involvement.

Footnotes

1. ↑ the words "buffalo" and "bison" are often used interchangeably in popular parlance; however, the scientific name for this North American bovine is "bison".

External links

• Environment Canada's Species at Risk website profiles the Wood Bison
• Photo gallery
• Alaska.org

eo:Arbara bizono no:Skogsbison