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© David J. Phillip/APExterminator Tom Rasberry lets his namesake crazy ants crawl on his arm in 2008. The ants don't bite, but they can cause more trouble than fire ants.

There's a new ant in town, and wherever it goes, fire ants start disappearing. It also doesn't sting or bite. But don't get excited yet. The Rasberry crazy ant which showed up in Travis County and Round Rock this fall swarms into homes by the hundreds of thousands in search of food.

In the Houston area, where the ants are much more prevalent, they have already made some homeowners miserable, said Roger Gold, professor of entomology at Texas A&M University.

"People that have them said they wish they had the fire ants back," he said. "We have pictures of families sweeping them up with brooms where there are piles of ants. ... They can get into AC systems and short them out."

When the ants get electrocuted they produce a pheromone that causes other ants to rush in, Gold said, leading to so many ants in the electrical system that it shorts out. An infestation of the ants temporarily shut down a Pasadena chemical plant, causing a $1 million loss, he said.

"They have huge populations made up of hundreds of thousands to multiple millions," Gold said.

Ed LeBrun, a research associate at the University of Texas' Brackenridge Field Laboratory, said the crazy ants haven't caused Central Texas the problems that have been seen in the Houston area, where they were discovered in Pasadena in 2002 by exterminator Tom Rasberry.

The ants were first sighted in Travis County when a homeowner found them at a condominium complex in the Briarcliff area on Lake Travis in November, said Harvey Jacks, who owns an extermination company called Assassin Pest Control.

"There were hundreds just covering the floor, and after we cleaned them up more of them just came back in," Jacks said.

He said he found out that the insects were crazy ants after sending a specimen to an entomology laboratory at Texas A&M.

Now he's treating three of the units monthly with pesticides and trying to get the rest of the neighbors involved, Jacks said. "There's no eradication for them; only control," he said.

No one knows exactly where the crazy ants came from because their species has not been identified, Le-Brun said, but "they are most likely the South American crazy ant."

Rasberry crazy ants have been discovered in 21 Texas counties, mostly in South Texas.

Crazy ants have also been found in Louisiana, Mississippi and Florida, but they are not the same species as those in Texas, said Danny McDonald, a graduate student and research assistant in the entomology department at Texas A&M.

In addition to infesting homes and electrical systems, the ants attack and kill honeybees with acid that they secrete from their bodies, McDonald said.

Gold said the ants could also pose a danger to livestock, such as chickens, by overwhelming their respiratory systems and causing them to suffocate.

Rasberry crazy ants are smaller than fire ants but are successful at driving them away because they compete with fire ants for food and usually win, LeBrun said.

Unlike fire ants, crazy ants will enter homes in search of sugar and pet food, Gold said.

LeBrun said thousands of the crazy ants are living under rocks along a 700-meter segment of Lake Travis in the same area as the condominiums where the ants were first found in Travis County.

"The most likely way they got there is they were brought in with landscape material from Houston," LeBrun said.

"The amount of area occupied by these ants out at Travis indicates that they have been there for a few years and gone unreported," he said. "It takes time for these populations to become dense enough that people find them problematic and call pest control operators."

Crazy ants don't live in mounds like fire ants but instead live under natural materials or under things people leave on the ground like mulch, landscaping materials and wood, he said.

Wizzie Brown, an extension program specialist with Texas Agrilife Extension Service, said she is working with people in the area to educate them about the ants.

She said she caught five to six crazy ants using hot dog slices as bait in a fire ant trap in a greenbelt in the Old Settlers Road area of Round Rock in October, but she wouldn't be specific about where the greenbelt was located.

LeBrun said it's hard to predict whether the crazy ant population will explode in Central Texas.

"This is as far west and as dry as they've been," he said. "They seem to be restricted to areas near the Gulf right now where there's high rainfall and high humidity," he said.

Gold had a grimmer view. The ants "will spread this year," he said.

One of the problems is there's no state or federal money available to study them, he said.

"We don't even have a handle on the spectrum of chemicals that are really effective on them," Gold said.