Weights and measurements of wintering Tundra Swans

Abstract

Tundra swans Cygnus columbianus columbianus were captured on their eastern USA wintering grounds in Maryland and North Carolina during 1966-84. Weights were taken on 3,583 of these swans and 581 were also measured for culmen, gape, nares-to-bill-tip, middle toe, and tarsus length. Each swan was sexed and aged as an adult, subadult, or juvenile. Significant differences in weights were found between age and sex groups, and within seasons. Variations in weights between years were examined for swans captured in late January and February. Significant differences were found in some structural measurements between sex and age groups.