Recent population trends of the eastern bluebird

ABSTRACr.-North American Breeding Bird Survey data for the period 1966-1987 indicate that Eastern Bluebird (Sialia sialis) populations declined during the 1970s, primarily in association with either severe winters or severe spring storms. In recent years, bluebird populations have increased to levels similar to those observed during the first year (1966) of the survey. Survey results suggest that climate has an important role in affecting shortterm population declines in bluebirds. Received 20 April 1989, accepted 27 Aug. 1989.