Crazy Ants: What Do They Do?

Crazy ants, particularly the Rasberry crazy ants (Nylanderia pubens), which were first found in Houston, Texas in 2002, are now infesting many parts of the US including Florida, Mississippi and Louisiana, according to recent reports. But what exactly are the effects of crazy ants?

Here's a discussion from the Department of Entomology of Texas A&M University in College Station, Texas.

Impact: What do they do?

In infested areas around the Houston area, large numbers of Rasberry crazy ants have caused great annoyance to residents and businesses. In some situations, it has become uncomfortable for residents to enjoy time in their yards. Companion animals may, in some cases, avoid the outdoors as well, and wildlife such as nesting songbirds, can be affected. The economic impact is currently unknown.

Biting and medical implications to people, livestock and wildlife: Rasberry crazy ants do not have stingers. In place of a stinger, worker ants possess an acidopore on the end of the abdomen, which can excrete chemicals for defense or attack. They are capable of biting, and when bitten, they cause a relatively sharp pain that quickly fades.

A related species in this genus, Nylanderia fulva, has been a serious pest in rural and urban areas of Colombia, South America. In this case, they reportedly displaced all other ant species and caused small livestock (e.g. chickens) to die of asphyxia. Larger animals, such as cattle, have been attacked around the eyes, nasal fossae and hooves. The ants also caused grasslands to dry out (dessicate) because the ants aggravated sucking insect pests (hemipterans) because the ants feed on the sugary "honeydew" produced by these plant feeding insects.

Electrical equipment: In areas infested by the Rasberry crazy ant, large numbers of ants have accumulated in electrical equipment, causing short circuits and clogging switching mechanisms causing equipment failure.

In some cases the ants have caused several thousand dollars in damage and remedial costs.

Agriculture: Todd Staples, Commissioner of Agriculture, suspects this to be a potentially serious agricultural pest (see Press Release). These ants show likelihood of being transported through movement of almost any infested container or material.Thus, movement of garbage (See image B below), yard debris (See image A below),bags or loads of compost, potted plants, bales of hay, can transport these ant colonies by truck, railroad, and airplane. No information is available on potential yield effects in infested lands.

Impact on Wildlife: Wildlife such as nesting songbirds is irritated by the Rasberry crazy ants. Masses of crazy ants covering the ground and trees likely affect ground and tree-nesting birds and other small animals and cause wildlife to move out of the area.

The ants are even displacing red imported fire ants in areas of heavy infestation. However, after experiencing the Rasberry crazy ant, most residents prefer the fire ant.

A related species of crazy ant has been a serious pest in South America, reportedly displacing all other ant species. In addition, the South American crazy ant pest caused chickens to die of asphyxia due to ants obstructing their nasal passages. Larger animals, such as cattle, have been attacked around the eyes, nasal area and hooves.

Source: http://urbanentomology.tamu.edu/ants/exotic_tx.cfm#impact