A frenzied pest has recently emerged, spreading rapidly across the southeast United States and causing headaches for homeowners, farmers, ranchers, and utility companies. Ongoing research at Sam Houston State University hopes to control the source of the outbreak, Rasberry crazy ants.
The Rasberry crazy ant (or tawny crazy ant), Nylanderia fulva, entered Texas less than 10 years ago from South America and have spread across Mississippi, Alabama, and Florida. Historically, the southeast Texas and Gulf Coast regions have been especially vulnerable to invasive species, such as fire ants, but crazy ants have ushered in a new set of problems for area residents.
Originally named after a Houston-area exterminator, Tom Rasberry, who first identified the insect in 2002, crazy ants are the focus of several Sam Houston State University researchers. Among these experts are Associate Vice President for Research Dr. Jerry Cook, 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 a 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 don’t have stingers and do not generally inflict painful bites, they are capable of causing a variety 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. To date, 24 Texas counties have reported localized infestations, with even larger areas suspected to have infestations as well. Dr. McDonald says the density of crazy ants clustered in singular infestations is enormous, far too large for homeowners to deal with on their own.
In East Columbia, for example, every home in the community is infested with blankets of crazy ants. A bed-and-breakfast operator in the town reports food left momentarily unattended on outside tables brings swarms of the ants, and equipment such as water well systems are completely coated with the insects. 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 byinvasive species – did not have an institute dedicated to invasive-species research and control. SHSU’s expertise in this subject, Dr. Cook observes, “made it 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 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 and implement effective management strategies quickly so as to prevent the ants from becoming as universally problematic as fire ants. With this goal in mind, finding a way to keep crazy ants from driving area residents up the wall has become a main focus of the Institute for the Study of Invasive Species.