ENVIRONMENT YUKON






Birds

Trumpeter Swan population monitoring

Significance

The Committee on the Status of Endangered Wildlife in Canada designated Trumpeter Swans as a species of Special Concern in April 1978. Their status was re-examined and they were found to no longer be at risk in April 1996, largely based on surveys of Trumpeter Swan breeding grounds in northern Canada and Alaska (COSEWIC 2011).

Trumpeter Swan in flight. Cameron Eckert.

What is happening?

  • Yukon has two swan populations—the Rocky Mountain Population and the Pacific Coast Population, surveyed since 1985 in Yukon and northern B.C.
  • The Pacific Coast Population breeds mainly in Alaska, but also in Yukon and northwestern British Columbia.
  • The Rocky Mountain Population breeds mainly in Alberta, western Saskatchewan, southern Yukon, and the Northwest Territories.
Figure 1: Distribution of Trumpeter Swan populations in Yukon and northern B.C. Blue squares are Pacific Coast Population. Purple squares are Rocky Mountain Population.
Figure 2: Preliminary population estimates for Yukon and northern B.C. Trumpeter Swans.
  • The 2015 estimate for the Canadian portion of the Rocky Mountain Population was 16,143, an 80 per cent increase compared to the 8,950 estimate for 2010.
  • The 2015 estimate for the Canadian portion of the Pacific Coast Population was 2,979, a 106 per cent increase compared to the 1,443 estimate for 2010.
  • All Canadian areas of the Rocky Mountain and Pacific Coast Populations exhibited growth since the 2010 survey.

Taking action

  • Surveys coordinated by Environment and Climate Change Canada in Yukon contribute to national and international trend and population estimates for Trumpeter Swans.
  • The Government of Yukon operates the Swan Haven Interpretive Centre, where visitors can view and learn about M’Clintock Bay on Marsh Lake, an important staging area for migrating swans, waterfowl, gulls and shorebirds.
Trumpeter Swans © Environment Canada, Jim Hawkings

Data quality

  • Continued monitoring of this species occurs through the North American Trumpeter Swan Survey. Yukon contributes survey information of its swan populations to the continent-wide monitoring.
  • The North American Trumpeter Swan Survey is conducted across Trumpeter Swan breeding grounds every five years. Surveys have been conducted since 1968.
  • The survey was originally designed as a complete census, i.e., counting all the birds across the entire range. By 1995, increases in the Trumpeter Swan population made a complete census unfeasible and a stratified random sampling approach was adopted, i.e., randomly selecting map grids to survey which are likely to have breeding swans.

References

Canadian Wildlife Service Waterfowl Committee. 2015. Population Status of Migratory Game Birds in Canada: November 2015. CWS Migratory Birds Regulatory Report Number 45. Available from: https://www.ec.gc.ca/rcom-mbhr/default.asp?lang=En&n=9DB378FC-1#_2_40.

Committee on the Status of Endangered Wildlife in Canada (COSEWIC). 2011. Canadian Wildlife Species at Risk. Environment Canada, Gatineau, Quebec, Canada.

Groves, D.J., compiler. 2012. The 2010 North American Trumpeter Swan Survey. U.S. Fish and Wildlife Service, Juneau, Alaska, U.S.A. Available from: http://www.trumpeterswansociety.org
/docs/North%20American%20TRUS%20Survey/2010/Rept.pdf