The Where + Why: Ants on the Move

“Warming environments are favorable for ants. They reproduce faster, they have more to eat and more opportunities to be pests when the environment is warmer. They’re going to do nothing but increase,” said John Cooksey, COO of McCall Service, Jacksonville, Fla., who expects to see more invasive ants entering the scene, as well.

One of these is the little yellow ant (Plagiolepis alluaudi), a Madagascar native, recently found in Fort Lauderdale, Fla. Entomologists also reported higher numbers of ghost ants (Tapinoma melanocphalum) in greater Houston and Aphaenogaster ants, or winnow ants, around structures in parts of Tennessee. “Maybe it’s nothing; maybe climate change is affecting the species that we have closer to the structure now,” said Dr. Karen Vail, University of Tennessee urban entomologist on observing more Aphaenogaster ants.

In Hawaii, introduced odorous house ants (OHA) have established supercolonies that could disrupt the natural ecosystem. Warmer temps in Illinois have been a boon to OHA, as well. “The ants have adapted dramatically to this part of the country (in ways) that we have not seen 10, 15 years ago,” said Gary Pietrucha, president, Envirosafe Pest Management, Itasca, Ill.

Favorable climate conditions also are helping the red imported fire ant continue to spread across North Carolina, reported N.C. State University. The state quarantine for the pest now includes portions or entire areas of 75 counties.

Cooksey has his hands full with the invasive tawny crazy ant, which forms mega-colonies that can encompass several acres. Treating one house for the pest when the colony covers the entire subdivision isn’t going to get rid of the problem, he said. “What it takes is a large-scale baiting program over a couple of acres instead of a couple of thousand square feet, which is what we normally contract,” said Cooksey.

He has achieved control at large commercial facilities, such as industrial warehouse and food-processing complexes, using liquid bait outdoors in stations designed to prevent the ants from falling in and fouling the bait.

Because they’re so difficult to control, tawny crazy ants are not covered in McCall Service’s annual contract. Explaining this to clients requires excellent communication skills, said Cooksey.

The author is a frequent PCT contributor.