| Nylanderia cf. pubens | |
|---|---|
| Scientific classification | |
| Kingdom: | Animalia |
| Phylum: | Arthropoda |
| Class: | Insecta |
| Order: | Hymenoptera |
| Family: | Formicidae |
| Genus: | Nylanderia |
The crazy Rasberry ant or Rasberry crazy ant is an invasive species of ant found near Houston, Texas.[1][2]
While this species is part of the crazy ant complex (group named because of the ants' random, nonlinear movements) the media and others in Texas are also calling it "Rasberry" after the exterminator Tom Rasberry who first noticed the ants were a problem in 2002.[1] This ant has yet to be identified as a species due to confusion regarding the taxonomy of the genus, and has for now been scientifically named Nylanderia species near pubens, more commonly shown abbreviated as Nylanderia sp. nr. pubens.[3] The abbreviation "sp. nr." means that this ant may or may not be the same ant as Nylanderia pubens, the Caribbean crazy ant.[4]
There is currently a large infestation in at least 20 counties in Texas. The ants appear to prefer the warmth and moistness of the coast.[5]
Contents |
The ants are about 3 millimeters long (equivalent of one-eighth inch) and are covered with reddish-brown hairs. The colonies have multiple queens.[6] They feed on ladybugs, fire ants and Attwater's prairie chicken hatchlings, as well as plants.
They are able to out-compete fire ants because they reproduce faster.[5] The ants are not attracted to ordinary ant baits, are not controlled by over-the-counter pesticides,[7] and are harder to fully exterminate because their colonies have multiple queens.[8]
It is unclear why this species, like many varieties of ants, is attracted to electrical equipment.[9] It may be that they sense the magnetic field that surrounds wires with electric current flowing through them. Or, they might prefer the heat byproduct of resistance in the wires. However, it could simply be that they are searching for food or a nesting location that is easy to defend.
Their infestation of electrical equipment can cause short circuits when they chew through insulation. Overheating and mechanical failures can also be caused by high numbers of dead worker ants in electrical devices.[10]
When an ant gets electrocuted and dies, it releases a chemical which causes the other ants to rush over and search for attackers. A large enough ball of ants will short out some systems. [11]
The coverage rate of the ant itself is about 800 meters (about ½ US mile) per year. However, being carried by people, animals, and vehicles, the crazy Rasberry ant has covered five counties in Texas from 2002 to 2007. This yields a rate of 8 kilometers (about 5 US miles) per year. At this accelerated rate, it would take about 70 years for them to reach New Orleans, 563 kilometers (or 350 US miles) away.
In June 2008, the Environmental Protection Agency granted temporary approval for the use of fipronil to control this ant. The pesticide is already used for termite control. Its use is restricted to seven counties in the Houston, Texas area.[12] As of May 2009, the ants continue to spread and have reportedly caused millions of dollars in damage in 11 Texas counties.