Lawrence LeBlond for redOrbit.com – Your Universe Online
A growing epidemic is eating its way across the Gulf Coast of the US and it seems there is little that can be done about it. The invasive ant species, Nylanderia fulva, commonly known as the tawny crazy ant, hairy crazy ant or Raspberry crazy ant, which was first discovered in Houston, Texas in 2002, is causing huge problems for people in at least four states around the Gulf of Mexico.
The tawny crazy ant is an exotic species native to South America, specifically Argentina and/or Brazil. Since it was first spotted by a pest control worker in Texas in 2002, it has been subsequently spotted in Mississippi, Louisiana and Florida. In Florida, some reports have estimated that N. fulva has been plaguing the Sunshine State since the 1990s, pushing out the crazy ant´s native cousin, N. pubens.
The ant has been named “crazy” for the trail of destruction it leaves in its wake. The tiny (less than an eighth-inch long) insect has been known to eat everything from livestock to electrical equipment. Singularly, these specimens may not seem so harmful, but at times millions have been found hiding under rocks, inside computers and elsewhere, devouring everything it touches.
The ant is now known in at least 21 counties in Texas and 20 in Florida, transported to all areas unwittingly by humans. While its bite isn´t known for stinging, it is highly invasive and has infested homes, RVs, computers, laptops, smartphones, and wildlife across the south.
Edward LeBrun of the University of Texas, Austin, said these invasive pests are displacing fire ants in areas across the southeastern US. They are also reducing diversity and abundance across a range of other ant and arthropod species. He said their spread can be controlled if people are more careful when they travel.
LeBrun, who is a research associate with the Texas invasive species research program at the Brackenridge Field Laboratory in the College of Natural Sciences, published a study on the invasive ant species in April 2013´s issue of Biological Invasions.
People are wishing their fire ants are back, realizing they are relatively calm compared to the voracious crazies, according to LeBrun. “Fire ants are in many ways very polite. They live in your yard. They form mounds and stay there, and they only interact with you if you step on their mound.”
Crazy ants, unlike the fire ants, “go everywhere.” And they are the worst of all ant invasions seen in the US to date.
In late 1800s, the Argentine ant invaded the US through the port of New Orleans. In 1918 the black imported fire ant showed up in Alabama. In the 1930s the red imported fire ant arrived and began displacing the black fire ant and the Argentine ant, according to LeBrun.
In the tawny crazy ant´s native habitat — Argentina and Brazil — it is likely that the population is held in check by other ant species and a variety of predators that feed on them. However, in the US there are no such natural predators, and the US native ant species are not as aggressive as those farther south.
Another issue that has arisen is the fact that these crazies are much harder to kill than other ants. Most colony ants are generally controlled by placing poison ant baits out, where they go and consume them and bring the death to their colony. But the crazy ant does not fall for this trick. And because the crazy ant does not have any particular colony boundary, if they are in fact killed in a certain area, the sheer size of the supercolony survives and can fill back in the area that was previously wiped out.
The biggest threat from N. fulva is the threat to electronics. According to ABC News, the crazy ants have caused more than $146.5 million in damages to electrical equipment in one year alone, just in Texas.
But with electronics, the whole ordeal seems rather tragic, not just for the electrical equipment, but for the ant as well. For example: when an ant touches a hot wire it will be electrocuted. When this occurs, the ant immediately performs what is called gaster flagging, which is an instinctual move that releases pheromones, luring more of its relatives to the scene. As each of these ants arrive and touch either the dead ant or another hot wire, they too will fry and release pheromones. Eventually, with so many ants arriving on the scene, circuits get overloaded and short out.
LeBrun said the single biggest role humans can play in keeping these pests from spreading is to check luggage, clothing and other items before traveling. The breeding members of the ant species cannot fly, so they are fairly limited to their range — generally traveling less than 650 feet per year.
Cutting down on the number of transplantation events could slow the spread of the insect by decades, said LeBrun. That extra time could be enough to give the ecosystem time to adapt to the insect and researchers more time to develop better control techniques, he added.
“We can really make a difference,” he said, “but we need to be careful, and we need to know more.”