Insects
About the Giant Crane Fly
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Class: Diptera Order: Tipulidae Family: Tipula

Crane flies are often mistaken by people as giant mosquitoes. In fact, that’s not too far off! Crane flies are the largest insects of the order, Diptera that includes mosquitoes.

What do crane flies look like?

The adult crane fly has two large, clear wings, and delicate, gangly legs. It is usually orange in colour with a pointy abdomen. Unlike its cousin the mosquito, the crane fly has a jerky flight that makes it look like it can’t fly very well at all. It is actually one of the largest flies in the world, with a wingspan, or at least a legspan, that can reach across your palm.

Crane fly larvae are often called "leather jackets", because in some species they have a tough, grey, brown or black covering. They are usually between 2.5 and 5 cm in length, but some can grow up to 10 cm long. It has a segmented body with no legs with a few finger-like lobes at the hind end.

Food for thought . . . Younger naturalists should try to leave crane flies alone. If you try to catch one, it will fall apart in your hands. Its giant legs practically fall off when they are touched.

Where do crane flies live?

Crane flies are found all over the world and more than 6000 species have been identified.

Crane fly adults are mostly found near water or moist areas. It is thought that crane flies are for the most part vegetarians, but very little is known about their feeding habits. They only live for a few days after they emerge from the pupa.

Crane fly larvae are very versatile, and can be found in water to damp vegetation to soil. They can be very good swimmers, and feed on rotting plants, or shoots and roots of living plants if they are in soil. Some species are carnivorous, and others damage the roots of cereal and grass crops.

What is the life cycle of the crane fly?

Crane fly adults may lay their eggs over the water of a pond or lake, or on the vegetation near the lake shore. Click here to see the life cycle of a crane fly. The eggs hatch after about six weeks, and then the larvae live in the water or in moist soil. Some species spend one winter feeding before becoming adults. Others can live as larvae for up to five years.

In the spring the larvae enter a resting phase where they form into pupas and then emerge as adults. Crane fly pupae are hard to find – they hide themselves in around the rocks at the lake shores.

Food for thought – it is thought by naturalists that crane flies have evolved their breakaway legs to compensate for their large size. Their courtship patterns that can make them such an easy meal. A would-be predator often winds up with a leg or two, while the adult crane fly can continue relatively unbothered with even two of its six legs missing.



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