Crazy Ants Targeted by SHSU-Based Invasive Species Institute

Texas is being invaded… again. But thanks to ongoing research at Sam Houston State University, this time the invaders may not be here to stay.

The southeast Texas and Gulf Coast regions have always been especially vulnerable to invasive species, as anyone who’s had to deal with fire ants knows. The red imported fire ant is just one of several species that have caused big problems for area residents. 

Now there’s yet another problem insect that is causing headaches for homeowners, farmers and ranchers, and utility companies across the region: the Rasberry crazy ant (or tawny crazy ant), Nylanderia fulva. Crazy ants entered Texas less than 10 years ago from South America. The ants have also invaded Mississippi, Alabama, and Florida.

crazy ants 4Originally named after a Houston-area exterminator, Tom Rasberry, who first identified the insect in 2002, Rasberry (or tawny) crazy ants are the focus of several Sam Houston State University researchers. Among these experts are Associate Vice President for Research Dr. Jerry Cook (left), who is also Executive Director of The Texas State University System’s Institute for the Study of Invasive Species (ISIS), and Dr. Danny McDonald, a research scientist at the institute and an SHSU biological sciences graduate, who earned his Ph.D. at Texas A&M University with a dissertation investigating various aspects of crazy ants.

Though crazy ants, unlike fire ants, don’t have stingers and do not generally inflict painful bites or stings, they cause plenty of other problems. Pets and wildlife avoid contact with the ants, grasslands can dry out because the ants feed on a sugary substance produced by insects that are beneficial to plants, and livestock have been attacked near their eyes and other body areas.

In search of warmth, crazy ants also tend to accumulate in large numbers in switch boxes and other electrical gear, which can cause short circuits and equipment failure problems for electric utilities. 

Large infestations of the insects have been found in communities south of Houston such as East Columbia, Pasadena, and Texas City. In all, 24 Texas counties have reported localized infestations so far, with even larger areas suspected to have infestations as well. Dr. McDonald says that the numbers involved in individual infestations are enormous, far too large for homeowners to deal with on their own.

crazy ants 1In East Columbia, for example, every single home in the community is infested with crazy ants. A bed-and-breakfast operator in the town reports that food left unattended outside on a table for just a few minutes brings swarms of the ants… and equipment such as water well systems are completely coated with the insects, too. In nearby LaMarque, where Dr. McDonald has conducted research for two years with the cooperation of homeowners Susan and Gattis Wittjen, the ants’ numbers are similarly large. The Wittjens sweep up a dustpan full of the ants on a daily basis, and they’ve found that exterminators can provide no more than a month’s relief before the ants come back. Once, after returning from a vacation, they swept up piles of the dead insects large enough to fill an entire grocery bag!

Fortunately, the ISIS Center - based at SHSU and located in the laboratories of the university’s Texas Research Institute for Environmental Studies (TRIES) - is on hand to help address the crazy ant problem. Dr. Cook noted in an interview that before the center was established, Texas and the region – so susceptible to problems caused by invasive species – did not have any institute dedicated to invasive-species research and control.  SHSU’s expertise in this subject, Dr. Cook observes, “made it a natural that we would start to develop a center, and what we’ve come up with is probably the most comprehensive center in the United States.” The need for institutes like ISIS is stark: Invasive species cause $130 billion in damage every year in the U.S., making them a huge and continuous natural disaster.

Dr. McDonald, Dr. Cook, and their colleagues at ISIS are determined to help people in communities infested with crazy ants. They are hoping to find effective management strategies soon – still relatively early in the invasion – so they can prevent the ants from becoming as big a problem as fire ants have been over the last decades. With this goal in mind, finding a way to keep crazy ants from driving area residents crazy has become a main focus of the Institute for the Study of Invasive Species.