'Crazy ants' invade Southern states, altering ecosystem

Lindsay Friedman | USA TODAY

If you're in Texas, Florida or other Southern states this summer, watch out for "crazy ants," warns Edward LeBrun, a University of Texas research associate who studies the species.

Also known to scientists as Nylanderia fulva, they're called crazy because of their unpredictable movements and swarming populations. The bug is reddish-brown, about an eighth of an inch long and has a hankering for honey dew — with a side of electronics. The insects nest anywhere and are easily transported, but so far have mostly infested Texas and several Southern states after being inadvertently transported from South America by humans.

They've spread to 24 counties in Texas, 20 in Florida and a few in Mississippi and Louisiana, according to LeBrun's study, published in the journal Biological Invasions. They cause about $146.5 million in electrical damage a year because millions of ants are electrocuted in small circuits or wires, where they seek warmth, according to a Texas A&M University study published in April.

There's no permanent solution yet, and fending off the ants is costly because of the need for repeated treatments. Without them, the ants would return with a vengeance from untreated neighboring areas.

Susan and Paul Dans of Baytown, Texas, know all about that, having fought the nuisance since 2011, when millions of crazy ants invaded their 3-acre lot.

Struggling to keep the ants at bay using chemical sprays every two weeks, Susan Dans says she "felt overwhelmed," fearing the ants would cause more damage. It became difficult to walk or stand outside — she couldn't even let her dogs out in the yard.

"It's just a frenzy," she says. "They're everywhere."

Then the couple saw a TV interview with Tom Rasberry, the Texas pest terminator credited with identifying the vexatious beasts in 2002. Rasberry says he has been able to ward them off and, on two occasions, eliminate an entire colony with the insecticide Termidor (fipronil), a poisonous chemical. Initially used for termites, it was approved for emergency use only in Texas by the EPA. If used incorrectly, it can be deadly for bees, birds and aquatic animals, including fish.

"We can kill them," he says. "But unless you can control the entire area, the best we can do is keep them at bay."

Since the invasion three years ago, the Dans still must get treatments every three months, costing about $2,300 a year. Unable to afford protection for all of their land, they settle for a 1-acre barrier surrounding their home while they say the remaining 2 acres wastes away, decreasing their property value.

"It's sad because you have no control," Susan Dans says. "You just don't see daylight."

LeBrun's study says the ants aren't just a costly nuisance because they're displacing other aggressive species, such as fire ants — they're throwing the whole Southern ecosystem out of whack.

"It's not a good trade," says Robert Puckett, associate research scientist at Texas A&M University, who has also examined the species in separate studies. "Some people think they'd prefer to deal with crazy ants. But once they invade, people want their fire ants back."

Though crazy ants don't have a nasty stinger like fire ants, they do bite. Crazy ant mounds are also decentralized and can create larger super colonies. To make matters worse, the insect's kryptonite has yet to be discovered — typical insecticides have no effect.

In Colombia, they have replaced all other ant species, killing small animals by asphyxiation. They've attacked the eyes, noses and hooves of larger animals such as cattle, and dried out entire grasslands.

LeBrun says the invasion is "very concerning" because scientists from both South and North America know little about the ant.

The best thing to do, he says, is avoid transporting them by closely monitoring belongings and take advantage of available treatments until researchers can find better answers.

"We can really make a difference," he says. "But we need to be careful, and we need to know more."

Rasberry, however, isn't so optimistic.

"It's gone too far," he says. "There's no turning back."