The longest-lived Broad-tailed Hummingbird was a female, and over 12 years, 2 months old, when she was recaptured and rereleased during a banding operation in Colorado in 1987.When males dive down upon females during courtship displays they sometimes pin a female down if she is sitting in low vegetation.Before the next breeding season rolls around they grow new feathers and are ready to trill away. By midwinter the trill is often inaudible. Male Broad-tailed Hummingbirds produce a loud trill with their wingtips as they fly, but over time the feathers that produce this sound wear down from use.This move can reduce his energy costs of thermoregulation by about 15%. The nesting female copes with these temperature extremes by building a well-insulated nest and entering torpor, but the male often heads upslope, out of the pocket of cold air that collected in the valley. Even on summer nights, cold air often descends into mountain valleys, dropping temperatures to below freezing. The Broad-tailed Hummingbird is one tough hummingbird.In one feeder-rich area a male made over 40 chases per hour in an effort to keep all of the sugar water to himself. Breeding male Broad-tailed Hummingbirds dive at and chase away unwelcome visitors to their territories, and the better the territory the more chasing that occurs. Hummingbirds are energetic and aggressive little birds.It maintains a body temperature of about 54☏ (12.2☌) when ambient temperatures fall below 44☏ (10☌). The Broad-tailed Hummingbird enters torpor, a slowed metabolic state, on cold nights.
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