Hummingbirds use up a lot of energy during the day as they fly around in search of food and hover to eat. After a long day, they need a good night’s sleep to recharge and refuel. They typically sleep for 12 hours or more (from dusk until dawn). On average, hummingbirds spend half an hour before sunset in torpor, an extreme hibernation-like state that lowers their metabolism and heart rate, conserves their energy, and allows them to stay warm.
During the day, hummingbirds have an extremely high metabolism and are small, which makes them susceptible to cold weather and inclement conditions. Consequently, they find sheltered spots where they can protect themselves from predators and harsh weather. This is why they often find their way into trees and shrubs.
While hummingbirds usually sleep alone, they have been known to roost together on occasion. Group roosting offers additional protection from predators and provides some thermal regulation, as the birds can absorb warmth from one another and lose heat at the same time.
During the winter, hummingbirds go into a deep hibernation-like state called torpor. They enter this state by lowering their metabolic rate, fluffing up their feathers, and conserving as much energy as possible. This process is very similar to hibernation, but is short-lived and only happens during the winter. This sleep-like state allows hummingbirds to conserve enough energy to survive the winter and still be ready to feed during the day.