Hummingbirds are birds that comprise the family Trochilidae. hey are known as hummingbirds because of the humming sound created by their beating wings, which sometimes sounds like bees or other insects. To conserve energy while they sleep or when food is scarce, they have the ability to go into a hibernation-like state (torpor) where their metabolic rate is slowed to 1/15th of its normal rate. When the nights get colder, their body temperature can drop significantly and thus slow down their heart and breathing rate, thus burning much less energy overnight.
Insects: Small insects, larvae, insect eggs and spiders are critical food sources for hummingbirds. Insects provide the fat, protein and salts the birds cannot derive from nectar, and these are crucial nutritional components, especially for rapidly growing hatchlings. Hummingbirds may hunt insects in several ways, including gleaning them from bark, flowers or leaves, hawking them from the air or plucking them from spider webs or sticky sap. To get the required amount of protein for a healthy diet, an adult hummingbird must eat several dozen insects each day.
Sap: When nectar is scarce, hummingbirds will sip tree sap from wells drilled by woodpeckers. While the tree sap is not as sweet as floral nectar, it still provides an adequate source of sucrose for a hummingbird’s energy needs.
Pollen: Hummingbirds do not directly consume pollen, but a great deal of pollen can be stuck to their tongues and bills when they sip nectar from flowers. Some of that pollen is ingested, and it can be a minor source of protein. Less than 10 percent of the ingested pollen is actually digested, however, which shows that while viable, this is not a common food source for hummingbirds.