While hummingbirds are best known for their ability to hover in the air and paint the sky with color, these tiny creatures have an equally fascinating way of shutting down for a nap. They enter a state of torpor, or hibernation-like sleep, at night in order to regulate their internal temperature and conserve energy for the following day’s activities.
In this deep sleep, a hummingbird’s metabolism lowers to 1/15th of normal and they use 50% less energy than they would when awake. Their heart rate drops to 50 beats per minute and their breathing becomes so slow that they can sometimes seem like they aren’t even alive. It takes 20 minutes to an hour for a hummingbird to fully wake up and respond to external stimuli, which is why you might sometimes see them hanging upside down and appearing dead, when they are actually just sleeping.
Hummingbirds are solitary birds and typically rest alone when they’re not on their nest or visiting one of your hummingbird feeders. They look for sheltered places in trees or shrubs that offer protection from cold temperatures, preferring deciduous trees with lots of branches and leaves over evergreens like pine.
On cold nights, a hummingbird can save energy by lowering its metabolic rate and fluffing up its feathers to retain as much body heat as possible. They may also turn on the small lights on their tails to light up their surroundings. Unlike many other species of birds, hummingbirds don’t sleep in their nests (with the exception of female hummingbirds incubating eggs or keeping their hatchlings warm), but rather find protected spots where they can hang upside down or perch on tree and bush limbs.