Crane flies, often mistaken for large mosquitoes, are insects known for their slender bodies and exceptionally long legs. They are found worldwide in moist, temperate environments like vegetation near streams and lakes. Their diet depends on their life stage, with adults typically feeding minimally or not at all, while their larvae are active eaters.
Adult Crane Fly Diet
Adult crane flies have a very short lifespan, typically 1 to 15 days. Their primary purpose during this stage is reproduction. Many species do not eat at all, some even lacking functional mouthparts and relying on larval energy reserves. Those that do feed consume only nectar or water, providing minimal energy. This limited feeding reflects their focus on mating and egg-laying.
Larval Crane Fly Diet
The larval stage of the crane fly, often called “leatherjackets” due to their tough skin, is when most feeding occurs. These larvae are cylindrical, legless, and can range in size up to 4 cm. They typically inhabit moist environments such as soil, decaying organic matter, and aquatic settings. Larval crane flies primarily feed on decaying plant material, roots of various plants, including turfgrass, and sometimes fungi or small invertebrates.
Certain species of crane fly larvae, such as the European crane fly (Tipula paludosa) and the marsh crane fly (Tipula oleracea), are considered agricultural or garden pests. Their feeding on plant roots, especially turfgrass, can lead to visible damage like yellowing, thinning, or bare patches in lawns. This feeding activity occurs mostly underground, but on damp, warm nights, they may come to the surface to consume above-ground plant parts. The presence of these larvae can also attract animals like birds, skunks, and raccoons, which may further damage lawns while foraging for them.
Common Misconceptions About Crane Flies
Crane flies are frequently confused with mosquitoes due to their similar appearance, including long legs and slender bodies. Despite this, crane flies are harmless to humans and animals. They do not bite or sting, as most species lack biting mouthparts or only possess those for sipping nectar.
Another misconception is that crane flies, sometimes called “mosquito hawks” or “skeeter-eaters,” prey on mosquitoes. Adult crane flies cannot consume other insects, including mosquitoes. While some rare crane fly larvae may feed on mosquito larvae in aquatic environments, this is not widespread, and adults do not engage in such predation.