• An aerial view of Old Faithful erupting taken from Observation Point with the Old Faithful Inn to the side.


    National Park ID,MT,WY

Wetland Birds

Sandhill cranes walk in a marshy area.

Sandhill Cranes


Approximately 30 percent of bird species that breed in the park depend on wetlands. Scientists are concerned about these species because wetlands are expected to diminish as temperatures increase. They are monitoring the trumpeter swan, common loon, and colonial nesting species, such as the double-crested cormorant and American white pelican. Yellowstone has years of data about the rate and success of nesting for some of these species, but not enough information about changes in the timing of their nesting activity, which is an indicator of climate change.

A trumpeter swan sits on its nest.

A trumpeter swan on nest


Trumpeter Swan
Cygnus buccinator

This species is probably most imperiled in Yellowstone National Park. Longterm monitoring, research, and management continue. Trumpeter swans in North America neared extirpation in the early 1900s due to human encroachment, habitat destruction, and the commercial swan-skin trade. Small populations survived in isolated areas such as Yellowstone. Red Rock Lakes National Wildlife Refuge, west of the park, was set aside in the 1930s specifically for this species. In the 1950s, a sizeable population of swans was discovered in Alaska. Today, more than 46,000 trumpeters exist in North America. Their population in the Greater Yellowstone area (GYA) is considered stable, but the park's population is declining. In recent years, fewer than 10 swans have lived here year-round. Winter numbers vary from 60 to several hundred. Reproduction rates are low. Several factors may be contributing to this decline:

  • loss of wetlands during an extended drought in the late 20th and early 21st centuries
  • few trumpeter swans taking up residence in the park
  • competition with swans that migrate to the park for winter
  • increased predation by coyotes & wolves

Information on the GYA resident swan and winter swan populations dates back to 1931 and 1971, respectively. Federal agencies conduct two annual surveys: The February survey counts how many migrant swans winter in the region; the September survey estimates the resident swan population and annual number of young that fledge (leave the nest).

Trumpeter Swan Facts

loons, common loon

Common loon

The Common Loon
(Gavia immer):

The park's loon population is one of the most southerly breeding populations in North America and one of the only populations breeding in Wyoming (It is also the largest loon population in Wyoming.) Since 1987, park scientists have collected data on common loon nesting.

Did You Know?

Upper Geyser Basin Hydrothermal Features on a Winter Day.

Yellowstone contains approximately one-half of the world’s hydrothermal features. There are over 10,000 hydrothermal features, including over 300 geysers, in the park.