Trumpeter Swans

Two adult swans and young on water

Trumpeter swans are a species of concern in Yellowstone. A pair of trumpeter swans successfully fledged four young cygnets on Grebe Lake in 2012.



The trumpeter swan (Cygnus buccinator), named for its resonant call, is North America's largest wild waterfowl, with a wingspan of up to eight feet. These swans require open water, feed mainly on aquatic plants, and nest in wetlands. Although they once nested from Alaska to northern Missouri, trumpeter swans were nearly extirpated in the lower 48 states by 1930 due to habitat loss and hunting. Small populations survived in isolated areas such as the Greater Yellowstone Ecosystem, where the population was thought to number only 69.

As a result of conservation measures, populations across the continental United States began increasing. Today there are approximately 46,000 trumpeter swans in North America. Swans in the Greater Yellowstone Ecosystem played a significant role in the population resurgence, but by the early 1960s, cygnet production in Yellowstone and subsequent recruitment of adults into the breeding population began declining. Learn More: Trumpeter Swans Information Continued...


Quick Facts

Number in Yellowstone

11 resident swans in 2014, excluding releases and young of the year. Trumpeter swans are increasing in the Rocky Mountains, stable in the Greater Yellowstone Ecosystem, but declining in Yellowstone National Park.


  • White feathers, black bill with a pink streak at the base of the upper mandible.
  • During migration, can be confused with the tundra swan. Trumpeters are larger, have narrower heads, have a pink mandible stripe, have no yellow spot in front of the eye.


  • Slow-moving rivers or quiet lakes.
  • Nest is a large, floating mass of vegetation.


  • Feed on submerged vegetation and aquatic invertebrates.
  • Low reproduction rates.
  • Can fail to hatch eggs if disturbed by humans.
  • Lay 4–6 eggs in June;young (cygnets) fledge in late September or early October.
  • Usually in pairs with young in summer;larger groups in winter.

Management Concerns

  • Limiting factors in Yellowstone appear to be flooding of nests, predation, possibly effects of drought caused by climate change, and less immigration into the park from outside locations.
  • Because swans are sensitive to human disturbance during nesting, nest areas are closed to public entry.

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