(adjective) Describes a diet that consists primarily of insects, including aquatic insects, ants and spiders. Many birds have at least a partially insectivorous diet, and insects are a critical source of protein for many growing nestlings. While young birds are still dependent on their parents for food, they may be fed mostly insects, even if their mature diet will be much different. To be considered insectivorous, a bird does not necessarily need a diet of exclusively insects, but the insect proportion is quite significant.
Insectivorous birds forage in different ways. They may catch insects in flight or pick them from plants, leaves, water or leaf litter. Small birds are often seen hawking, a foraging method that involves small, hovering flights to pluck insects before returning to a nearby perch. Small birds of prey, such as the American kestrel, will hover or soar to find large insects in open fields.
While most birds will eat at least some insects, types of birds that are primarily insectivorous include swifts, swallows, flycatchers and warblers. Backyard birders can attract insectivorous birds by avoiding the use of insecticides and pesticides on their landscaping or by offering mealworms at their bird feeders. Some suet blends are also made with insects and mealworms.
Photo – Pied Flycatcher © Steve Garvie
Insect-Eating, Insectivore (noun)