The hardy Broad-tailed can be found at high altitudes in California and the southern and central Rocky Mountains. These little birds can tolerate temperatures that drop below freezing at night because they enter torpor, a slowed metabolic state where their body temperatures drop to about 54°F. The male Broad-tailed, who doesn't tend the nest, will move up from a mountain valley at night to where it is warmer, to conserve energy.
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