"Off With Their Heads!"

That's the battle cry of Sanford Porter. He's an entomologist in Florida who's enlisting head-hunting flies to battle nasty fire ants. These pesky ants are cropping up in suburban Florida and across the south.

You don't want to step on a fire ant mound--especially if you're barefoot. If they notice you there, you'll want to be someplace else--fast.

Why? Fire ants pack a powerful sting that can raise a painful red rash on people and animals. They also sting other bugs, including other ants whose turf they want to take over. Fire ants chew up crops, too.

They even get into electrical boxes and homes, where they cause more havoc.

Fire ants thrive in developing areas--shopping malls, housing developments, anywhere the ground is dug up. When the ground is disturbed and insects there are fighting for survival, fire ants often win out. That's because they don't have any natural enemies in this country.

	How many eggs does a fire ant queen usually lay in a day?
	A) 10
	B) 100
	C) 2,000

Now Porter has declared war on this fearsome ant. And his weapon is a tiny fly that is a natural enemy of the fire ant in South America, where these ants came from.

In nature, these parasitic flies are dive-bombers. But they don't pelt the ants with bullets or bombs.

Instead, here's what happens: First, a female fly hovers above the ants. They know she's there, and they raise their pincers to try to defend themselves. Some scurry back into the nest. But the fly is faster.

In the blink of an eye, she swoops down on a worker ant and jabs it with a needle-like tube. Then she darts off again before the ant can fight back.

What she's done with the tube is place a fly egg inside the ant's body. From that egg, like a tiny time bomb, a hungry fly maggot will hatch a few weeks later. The maggot begins eating the ant from the inside out. Then the maggot starts "digging" tunnels into the ant's head.

Talk about your splitting headache!

But it gets worse. After the maggot tunnels inside the ant's head, the head falls off. The head then becomes the maggot's safe and tasty "home" where it stays while it grows into an adult fly.

Porter says the flies attack only fire ants. That's good news for animals, people and helpful insects like bees.

Starting spring 2001, Porter and other scientists began mass-rearing the phorid flies for release in test sites in Florida, Georgia, North Carolina, South Carolina, Louisiana, Mississippi, Texas, Alabama, Arkansas, Oklahoma, and Tennessee.

Most likely, the pest ant came to the U.S. in the 1930s by hitching a ride on cargo ships from South America. Now, it infests 310 million acres in the southern United States and Puerto Rico. But Porter hopes that giving the ants a natural fly-driven "headache" will make them less of a nuisance.

--By Jan Suszkiw, Agricultural Research Service, Information Staff, and Tara Weaver-Missick, formerly ARS Information

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