What does it look like?
The adult crane fly is large and fragile with long slender legs. Its body length varies from 1/8 inch to 3 inches. It looks a little like a huge mosquito. Its long legs make it a relatively poor flier compared to other flies. Just behind and at the base of the wings is a pair of balancing organs, called halteres.
Because of its unusual appearance, there are many different names for the crane fly. Among the names are gallinipper, gollywhopper, jimmy spinner and mosquito hawk. Its common name in the United Kingdom, and Ireland is daddy long-legs.
Scientists consider the crane fly to be a “true fly” because it has only one pair of wings.
The female abdomen ends in an ovipositor for laying eggs. The ovipositor is pointed and looks like a stinger but is completely harmless.
Where does it live?
Crane flies are found all around the world in temperate or tropical climates. At least 14,000 species of crane flies have been described worldwide. They can be found in lawns and turf, and in moist soil around ponds and streams. Compost piles provide an attractive home for crane flies. They rest on the soil surface just below the decaying vegetation.
This species has a broad range of habitats. It lives in cold arctic tundra and sub-arctic spruce forests. It likes white pine, jack pine and other evergreens in the northern Great Lakes region. East of the Mississippi River and southward along the Appalachian Mountains, it lives in forests of beech, maple, hemlock, and birch.
The crane fly usually likes moist environments such as woodlands, streams and flood plains. But some species inhabit open fields, dry rangeland, and even deserts.
What does it eat?
The crane fly is sometimes called "mosquito hawk" or "mosquito lion." Despite this ferocious name, it does not actually eat mosquitoes. The larvae of crane flies occur in moist soil, forest leaves and wood litter and in aquatic habitats associated with organic matter, depending on the species. Most species are generalist detritivores, but a few may feed on living plant tissue, such as grass roots.
Many adult crane fly have no mouthparts, so never eat at all. Those species that do have mouthparts will lap up sugar-rich plant nectar.
How does it defend itself?
The adult crane fly has little in the way of defense. It falls prey to birds, bats, cats and yellow jackets. Unlike most flies, it is a weak, poor flier with a tendency to "wobble" in unpredictable patterns during flight. It can be caught without much effort.
The way its delicate legs break off, even without direct contact, may help it evade predators.
In its larval form, the crane fly is defenseless. The larvae are often eaten by birds, such as robins and starlings. In addition to birds, there are many natural enemies beneath the soil. Tiny parasites, beetles, frogs, and small mammals attack the larvae in the wintertime.
What stages of metamorphosis does it go through?
The crane fly goes through a complete metamorphosis. The adult emerges from late August to mid-September, mates and lays eggs. The female lays most of her eggs before making her first flight.
The eggs hatch quickly in the soil. As they develop, the gray-brown, worm-like larvae begin feeding on roots in moist soil. The feeding is slow in the winter, speeds up in early spring, and ends in mid-May. The larvae change to quiet pupa in July and August. The leathery, shiny pupal case is called a “leatherjacket.” The adult crane fly comes out of the ground in August and September, living just long enough to mate and lay eggs.
What special behavior does it exhibit?
Crane fly larvae are called “leatherjacket slugs" because of their movement and the way they sometimes damage plants.
The adult snow crane fly is unusual because it emerges from snow in very cold temperatures. It is frequently seen crawling sluggishly on the surface after a fresh fall of snow. Some scientists believe it lives in nests of small mammals, such as mice and chipmunks. Its natural history is still largely a mystery.
How does this bug affect people?
The crane fly is an insect that appears to be a giant mosquito, but it does not bite. It is not generally considered a pest. In certain circumstances, the crane fly can be a problem in lawns and landscape plants, but not often.
Some crane fly larva feed on roots in nurseries that sell turf and seedlings. Cereal and grain crops are sometimes damaged by crane fly larvae. Most of the time, healthy lawns and plants can tolerate their presence as long as natural enemies keep populations down.
The crane fly is an important food source for birds, fish, and other animals. As an aquatic insect it can be an indicator of good water quality. Its larvae are important decomposers that break down waste in streams and soil. This activity creates rich organic material used by other organisms. Crane fly larvae attract fish looking for food. Fishermen even design their lures to mimic crane fly larva.
AgriLIFE Extension. A field guide to common Texas insects.