A bull moose in winter in a meadow

Bull moose usually shed their antlers in the beginning of winter to help conserve energy and survive the winter.



Moose in Yellowstone are one of four subspecies of moose (Alces alces shirasi) in North America, and are found in forested areas and willow flats from southeastern British Columbia to northern Colorado. They are better adapted to survival in deep snow than other ungulates in Greater Yellowstone. Except during the rut, moose are usually found alone or in small family groups. This behavior, and their use of habitat where they are often well concealed, impedes accurate estimates of population size and distribution. Learn More: Moose Description and Population...


Quick Facts

Number in Yellowstone

  • Fewer than 200
  • Population has declined in last 40 years due to loss of old growth forests surrounding the park, hunting outside the park, burning of habitat, and predators.

Where to See

  • Marshy areas of meadows, lake shores, and along rivers.

Behavior and Size

  • Adult male (bull) weighs close to 1,000 pounds; female (cow) weighs up to 900 pounds; 5½ to 7½ feet at the shoulder. Young weigh 25–35 pounds at birth.
  • Usually alone or in small family groups.
  • Mating season peaks in late September and early October; one or two calves born in late May or June.
  • Lives up to 20 years.

More Information


The list below includes academic publications, government publications, management documents that inform the decision-making process at parks and protected areas, as well as links to websites that provide additional relevant information. The Yellowstone Resources and Issues Handbook, updated annually, is the book our rangers use to answer many basic park questions.

Barmore, W.J. Jr. 2003. Ecology of ungulates and their winter range in Northern Yellowstone National Park, Research and Synthesis 1962–1970. Yellowstone Center for Resources.

Becker, S.A. 2008. Habitat selection, condition, and survival of Shiras moose in northwest Wyoming In Department of Zoology and Physiology. M.S. University of Wyoming.

Tyers, D.B. and L.R. Irby. 1995. Shiras moose winter habitat use in the upper Yellowstone River Valley prior to and after the 1988 fires. Alces 31:35–43.

Tyers, D.B. 2008. Moose population and history on the northern Yellowstone winter range. Yellowstone Science 16.

Did You Know?