Wood bison


Wood bison are North America’s largest land mammal. They are easily recognized with their large head, shoulder hump and shaggy coat on their shoulders and front legs.Their fur ranges from brown on most of the body to black on the head. 

Both sexes have short black horns. Female horns curve to point to the rear while male horns curve slightly inward. Males are larger than females and can reach weights of over 900 kg, stand 1.8 m in height at the hump and reach 3.8 m in length.


Wood bison are found in three populations in the Northwest Territories (NWT): the MackenzieNahanni, and the Slave River Lowlands.  

Bison numbers are estimated from aerial population surveys conducted in late winter. Bison can be classified into different sex and age categories by their size and horn shape. These ground-based surveys are carried out in July. The Mackenzie population experienced a large decline from 2012 to 2013, due primarily to an anthrax outbreak, but seems to be recovering. In 2019, the population was estimated to be about 1,470 animals.


Bovine tuberculosis and brucellosis are endemic in the Slave River Lowlands and Wood Buffalo National Park populations but the Mackenzie and Nahanni populations are free of those two diseases. The Bison Control Area is a program to reduce the risk of disease transmission to the Mackenzie and Nahanni populations.

Recovery strategy

The Recovery Strategy for Wood Bison in the Northwest Territories guides the development of management plans for each of the wood bison populations in the NWT. The management plans, developed in partnership with the Tłı̨chǫ Government, Wildlife Management Boards and community stakeholders, will contain objectives and actions to sustain and recover healthy wood bison in the NWT.


Wood bison are listed as a Threatened species in the NWT and in Canada.

Bison Hunt Report Form

Resident hunters with a tag to hunt wood bison in Unit U (Slave River Lowlands herd) must complete a Resident Hunter Mandatory Bison Hunt Report Form whether or not a bison was harvested.

Safety in bison country

Motor vehicle accidents continue to be a major mortality factor for wood bison in the NWT. The most dangerous time for collisions with bison is August through November, especially along the following highways: 

  • Highway 3 – Fort Providence to Yellowknife
  • Highway 5 – Fort Smith to Big Buffalo Junction
  • Highway 7 – Poplar River to British Columbia border

Bison are unpredictable and can run three times faster than humans. During the July-September mating season (rut) bulls are more aggressive and may pose an increased danger.

For more information on bison safety, read our brochure or visit the website for the Department of Infrastructure.