Calm down! Crane flies may look like huge mosquitoes but they don’t bite

They look like huge mosquitoes with delicate, matchstick legs and a bumbling, erratic flight. Actually they’re crane flies, harmless relatives of mosquitoes, and they often show up at porch lights or even find their way into our houses.

I saw hundreds of these fragile insects recently outside our daughter’s home near Columbia. They were fluttering all over the lawn and clinging to the sides of her house.

Many had paired up and were in the process of mating, and most would die within two weeks. Life is short for adult crane flies.

Like mosquitoes, house flies, no-see-ums, and other “true flies,” crane flies have just one pair of functional wings. The second pair of wings, called halteres, are fashioned into knobby gyroscope-like structures that help stabilize flight.

There are over 15,000 kinds of crane flies around the world and 1,500 in the U.S. alone.

Crane flies are sometimes called daddy longlegs, a name also applied to a group of spider-like arachnids.

Their wormlike, legless larvae live in freshwater, moist soil or organic matter. A few eat other insects, but most feed on decaying vegetation or the roots of plants.

Native crane flies can sometimes be a nuisance when they emerge en masse. However, it’s the European crane fly (Tipula paludosa), a non-native, invasive species, that causes the most damage. Its larvae are significant pests of turf grass in some parts of the U.S.

As larvae, crane flies are voracious feeders. After several months or longer, depending on the species, they enter the pupal stage, during which they gradually morph into the long-legged adults.

Then they begin their wobbly, awkward flight in search of mates, sometimes losing a skinny leg or two in tall grass or after encountering an obstacle along the way.

Some naturalists speculate that shedding limbs may distract a predator while the rest of the crane fly escapes unharmed.

At any rate, such mishaps don’t seem to hamper crane flies very much, since females have been seen laying eggs as usual despite losing half their legs.

As adults, some crane flies may feed on nectar. But despite another of their common names – mosquito hawk – adults don’t catch mosquitoes or any other live prey.

Most don’t even eat at all.

And despite their intimidating appearance, crane flies don’t bite or sting.

This story was originally published March 27, 2017 at 6:08 AM with the headline "Calm down! Crane flies may look like huge mosquitoes but they don’t bite."