The hummingbird’s fast breathing rate, fast heartbeat and high body temperature require that they eat often.
Hummingbirds primarily eat flower nectar, tree sap, insects and pollen.
Nectar is a mixture of glucose, fructose, and sucrose, and is a poor source of nutrients, requiring hummingbirds to meet their nutritional needs by consuming insects
just like bees, they are able to assess the amount of sugar in the nectar they eat;
but they normally reject flower types that produce nectar that is less than 10% sugar and prefer those whose sugar content is higher.
Hummingbirds eat many small meals and consume around half their weight in nectar (twice their weight in nectar, if the nectar is 25% sugar) each day
For nutrition, hummingbirds also eat a variety of insects, including mosquitoes, fruit flies, and gnats in flight or aphids on leaves and spiders in their webs.
The lower beak of hummingbirds is flexible and can bend as much as 25 degrees when it widens at the base, making a larger surface for catching insects.
Hummingbirds hover within insect swarms in a method called "hover-hawking" to facilitate feeding.
Hummingbirds have a long tongue which they use to lick their food at a rate of up to 13 licks per second.