Broad-tailed Hummingbird - An Energetic Visitor
Broad-tailed Hummingbird Rocky Mountain summers are distinguished by warmer temps, colorful wildflowers and the metallic trill of thin air whistling through the wings of tiny migrants. Zooming through our high meadows, the broad-tailed hummingbird is an energetic visitor. Bursting onto the scene around May, they arrive from their sun-drenched homeland situated south of the border. These hearty birds have developed a unique characteristic that allows them to survive the harsh conditions present at such a high altitude. Broad-tailed hummingbirds save enough energy to survive the bitterly cold nights by lowering their internal thermostat, becoming hypothermic. This reduced physiological state is an evolutionary adaptation that is referred to as torpor. Torpor is a type of deep sleep where a bird's heart rate drops, breathing slows and its metabolic rate lowers by as much as 95%. By doing so, a torpid hummingbird can save up to 60% of its available energy as opposed to when ...