STATUS OF TUNDRA SWANS AND TRUMPETER SWANS IN MEXICO

摘要

We summarize Tundra Swan (Cygnus columbianus) and Trumpeter Swan (C. buccinator) observations from Mexico recorded by the U. S. Fish and Wildlife Service during January aerial waterfowl surveys, 1947-94, other winter surveys and observations, 1972-95, and band recoveries. Swans were not identified by species with certainty during aerial surveys, but were presumed to be Tundra Swans. A total of 121 swans, including five band recoveries was reported at 22 locations in seven Mexican states; 83 were in the Interior Highlands, 23 near the Gulf Coast, and 15 in Pacific Coast states. Most records were from Chihuahua (66), followed by Tamaulipas (23), Durango (13) and Sonora (11); eight were from three other states. The most commonly used winter area was Laguna de Santa Maria in northern Chihuahua where 29 swans were observed. Of 121 swans recorded, three were identified as Trumpeter Swans in Chihuahua (2) and Tamaulipas (1) and two others as possible Trumpeters in Durango. These data and information from other sources show that Tundra Swans and Trumpeter Swans are rare and irregular winter visitors, mainly to northern Mexico.