Hummingbirds are famous for their ability to hover at flowers, consuming nectar that fuels their rapid metabolism and incredibly fast wingbeats. This sugary liquid provides a quick source of carbohydrates, acting as the primary energy source for these tiny fliers. Despite this reliance on nectar, hummingbirds cannot survive on sugar alone. Small arthropods form a necessary component of their diet, providing essential protein.
The Essential Role of Protein
Nectar, whether from flowers or feeders, is a high-octane sugar solution that provides immediate fuel but lacks necessary nutrients. This creates a significant nutritional gap because nectar contains almost no protein, fats, or complex amino acids. To construct and repair muscle, bone, and feathers, hummingbirds must supplement their diet with animal protein.
Insects and spiders supply the complete profile of amino acids, minerals, and fats absent from nectar. These components are necessary for the growth and maintenance of body tissues. Without this protein-rich supplement, a hummingbird would be unable to sustain its body structure.
Protein Needs During Life Stages
The need for protein becomes significantly heightened during specific life stages. Female hummingbirds require large amounts of protein for egg development during nesting. Once the chicks hatch, they require a diet consisting almost entirely of protein to support their rapid growth, which parent birds provide through constant insect feeding.
Adult birds also undergo an annual molting process, which is energetically demanding and requires substantial protein to replace old feathers. During migration, the need for fat reserves and muscle repair drives the birds to increase their insect consumption. Insects and spiders can make up a large percentage of a hummingbird’s total food intake during peak nesting and migratory seasons.
What’s on the Menu
Hummingbirds are not selective hunters, but the prey they consume is limited by the size of their narrow bills, meaning they must swallow targets whole. They generally target small, soft-bodied arthropods that are easy to capture and digest. Common prey includes tiny flying insects such as gnats, fruit flies, and mosquitoes.
They also regularly consume aphids, small beetles, and small wasps when available. A particularly important food source is spiders, or the small, soft parts of spiders. Hummingbirds will also consume insect eggs and larvae found attached to the undersides of leaves and bark.
The volume of insects consumed can be substantial; a single female feeding young sometimes catches hundreds to over a thousand insects a day. This high rate of consumption ensures they acquire the necessary nutrients. The small size of the prey ensures it can be quickly processed and delivered to the nestlings or used by the adult bird.
Hunting Strategies
Hummingbirds employ several distinct techniques to successfully capture their tiny prey, based on whether the insect is airborne or stationary. One common method is hawking, which involves darting out from a perch to snatch a flying insect directly out of the air. This aerial pursuit is similar to the foraging style of flycatchers, involving a rapid chase before the insect is captured in the bill.
Another strategy is gleaning, where the bird hovers briefly or perches to pick stationary prey off a surface. Hummingbirds precisely pluck small insects, eggs, or larvae directly off leaves, bark, or flower petals. This technique requires less energy than hawking and is used to harvest immobile food sources.
A specialized hunting behavior is web robbing, where hummingbirds intentionally visit spider webs to steal trapped insects. They are adept at extracting the prey without becoming entangled in the silk themselves. They sometimes consume the small spiders that built the web, adding another source of protein and fat to their diet. These diverse methods ensure that hummingbirds can exploit various environmental niches to fulfill their need for protein.