Crazy Ants
MCT file photo

With more than 150 resident ant species in Alabama, you would think we wouldn’t have room for one more.

Meet the tawny crazy ant — so named because they run around in crazy patterns.

There has recently been a confirmed sighting of the tawny crazy ant, Nylanderia fulva, in Mobile County, the first confirmed sighting in Alabama.

Tawny crazy ants were formerly known as Rasberry crazy ants, named after the pest control operator who first discovered them. The tawny crazy ant (also known as the Caribbean or hairy crazy ant) was originally found in Florida in 1953. Since its discovery, it has been sighted across southeast Texas, Louisiana, central and southern Florida and, just last year, in Albany, Ga.

Millions of ants per colony

Native to northern Argentina and southern Brazil, tawny crazy ants are small, brown ants, less than 2 mm long. Under a microscope or hand lens, you can see the ants’ hairy body.

Despite their small size, it’s their incredible populations that give them away. In a given area, crazy ant populations are 100 times greater than other ant species combined.

Because of the sheer numbers of tawny crazy ants, food sources are limited for other ant species. This is especially true for fire ants, which are displaced by tawny crazy ants.

That may sound like good news for those of us inundated with fire ant mounds. However, a colony of millions tawny ants is pretty scary. In areas where they have been found for years, it is not at all uncommon to shovel away dead tawny crazy ants by the five-gallon bucketful.

They are very opportunistic ants, invading electrical boxes, campers, homes and practically anything “just laying around.”

The foraging trails of these ants are very apparent. Their movement is erratic, and it often looks as though the ground is moving. The trail of ants may also follow structural lines around buildings..

Crazy ants are spread by humans

Tawny crazy ants do not have stingers. Good news, right? Instead of stingers, the workers have specialized pores on the ends of their abdomens, which excrete chemicals for defense or attack.

Tawny crazy ants are omnivorous. These ants will farm pests like aphids, scales and whiteflies that excrete a sugary excrement called “honeydew.”

Tawny crazy ants are very social, and colonies may grow to super-colony status. They also have polygyne colonies, which means colonies may contain several queen ants, which means their population increases rapidly.

Tawny crazy ants, unlike imported red ants, do not spread by mating flights. Current research suggests that tawny crazy ants must be picked up and moved by us.

Tawny crazy ants may invade campers on vacation. They may be present in potted plants or anything that they are able to crawl into. It is extremely important to check anything being moved from a known infested area.

How to manage crazy ants

Tawny crazy ants are hard to control. When they invade homes, indoor insecticides are not enough, since the colonies are often nesting outdoors.

In yards and gardens, remove anything that may become a nesting site including fallen limbs, unplanted plants and anything on the ground that doesn’t have to be there.

Tawny crazy ants prefer humid, wet conditions — another reason to plant drought-tolerant plants that do not need irrigation.

Crazy ants are not as attracted to the bait products that are often used to manage fire ants. Infested areas are often managed with contact pesticides applied in buffer zones around structures. For homeowners, using pest control operators is usually the best option.

Above all, remember that people are responsible for spreading tawny crazy ants. Please check anything that is moved from an infested site before bringing it home.

For more detailed information, a 45-minute webinar called “Ants! Ants! Ants!,” with Paul Nester of Texas A&M AgriLife Extension Service, is available at

Danielle Carroll is an extension agent for the Alabama Cooperative Extension System.