The straightforward answer to whether bees consume flies is no; common pollinating bees are not predators. The confusion is understandable because many insects that look strikingly similar to bees, including some wasps, actively hunt and eat flies. True bees belong to a separate lineage of insects whose diet is exclusively vegetarian, meaning they do not incorporate any animal matter into their nutrition.
The Typical Bee Diet: Nectar and Pollen
Bees are herbivores, relying entirely on flowering plants for their nutritional needs. They collect two primary resources from flowers: nectar and pollen. Nectar, a liquid rich in sugars, serves as the bee’s main source of carbohydrates, providing the energy required for flight, foraging, and regulating hive temperature. Pollen is the protein source, supplying the essential nutrients needed for the development of young bees, or brood. Worker bees mix the collected pollen with nectar or honey to create “bee bread,” which is fed to the larvae.
Distinguishing Bees from Predatory Wasps
The visual similarity between bees and predatory wasps is a form of mimicry that often causes mistaken identity. Bees, such as honey bees and bumble bees, have robust, rounded bodies covered in dense, branched hairs, which are adapted for collecting and transporting pollen. Their legs often feature specialized structures for carrying large loads of plant material. In contrast, predatory insects like yellow jackets and hornets possess a sleek, shiny, and relatively hairless body. Wasps typically have a much more slender connection between their thorax and abdomen, often referred to as a “wasp waist.”
Predators That Target Flies
The insects responsible for fly predation are generally wasps, particularly social wasps like yellow jackets and hornets. These insects are carnivorous, and flies are a frequent component of their diet, especially when provisioning their nests.
Social Wasps
Adult wasps consume sugary foods like nectar for energy, but their offspring require a high-protein diet for growth. Worker yellow jackets and bald-faced hornets actively hunt live insects, including flies and caterpillars. They process the prey into a meat paste before delivering it to the larval cells. A single hornet nest can account for the dispatch of thousands of flies daily, highlighting their role as biological pest control.
Other Fly Predators
Other solitary predatory wasps also target flies, often using specialized hunting methods. Tiny parasitic wasps attack the immature maggot and pupa stages of pest flies, laying their eggs inside to kill the developing fly. Robber flies, which are true flies themselves but often mistaken for a wasp due to their bristly appearance, are also expert predators that catch other flies mid-air.