US Fish & Wildlife Service
Date of this Version
U.S. Fish and Wildlife Service Migratory Birds and State Programs Mountain-Prairie Region Lakewood, Colorado.
Observers counted 371 swans (white birds and cygnets) in the U.S. Breeding Segment of the Rocky Mountain Population of trumpeter swans during fall of 2002, a decrease from 475 counted from comparable areas last year and the lowest count since 1993. The number of white birds (311) declined 23% from that of last year, while the number of cygnets (60) decreased by 15%. Declines occurred in all 3 states in which the Tri-state Area Flocks nest, and was greatest in Montana (-37%). Decreases in Idaho and Wyoming were 20% and 8%, respectively. The number of birds in restoration flocks also decreased 17% compared to the count from last year. The count for the Tri-state Area Flocks this year was a marked departure from their recent upward trend in numbers. The tri-state area continues to experience drought conditions, with Palmer Drought Index values the lowest recorded since surveys were initiated in the 1930s.
U. S. government work.