US Fish & Wildlife Service
Date of this Version
4-28-2006
Citation
U.S. Fish and Wildlife Service Migratory Birds and State Programs Mountain-Prairie Region Lakewood, Colorado.
Abstract
Observers counted 5,484 swans (white birds and cygnets) in the Rocky Mountain Population of trumpeter swans during February 2006, an increase of 2% from the 5,361 counted in February 2005 and the third consecutive record-high count for the Mid-winter Survey. The numbers of white birds (4,261) and cygnets (1,223) increased 1% and 6%, respectively, from counts last year. In the tri-state area, increases in total swans occurred in Montana (+47%) and Wyoming (+2%), but decreased slightly in Idaho (-5%). The number of birds wintering in areas near restoration flocks was slightly higher than the count last year. The number of swans counted in Oregon (50) was higher than that of last year and the 1997-2005 average. However, the count at Ruby Lake NWR was the lowest since 1994, and only about half of that observed during the mid- to late-1990s. The drought conditions that persisted in much of the tri-state area during the last several years abated somewhat, and reservoir levels in early February increased 19% from the very low levels recorded during 2004. Generally, temperatures during winter 2005-06 were slightly warmer than average, although temperatures dropped sharply in many areas of the tri-state region during February. Precipitation in primary winter areas was much above average from December 2005 through February 2006.
Comments
U. S. government work.