Army Ants

Facts, Identification & Control

Scientific Name: Ecitoninae spp.


Like other ant species, the bodies of army ants consist of a head, abdomen and thorax. The army ant’s thorax is located between the head and abdomen and is connected to the abdomen by joints known as nodes. Their abdomens are oval-shaped, and the stinger is located in this body segment. The head of the army ant has eyes, mouthparts and antennae. Their mouth consists of two jaws, or mandibles, which resemble scissors. Adult army ants are unable to eat solid items and ingest only liquids. They use their antennae to smell, touch and communicate with each other.

Behavior, Diet & Habits

There are over 200 species of army ants that exist worldwide. They are found in the southern United States, but are more common in Central America, South America, Africa and parts of Asia. Army ants are carnivorous, nomadic and aggressive. They attack freely; eat without discrimination; migrate to locate food sources; and maintain a complex social hierarchy.

Colonies of army ants consist of a queen, workers and soldiers. A single colony can contain up to 24 million individual ants.

Unlike other ant species, army ants are known to be nomadic, making temporary nests while traveling from one location to the next. Their nests are composed of the ants themselves: army ants form the walls of the nest by fastening their claws and mandibles to one another. During the nomadic stage, army ants march at night and stop to rest in daylight. This nomadic stage may last several days.

Workers are infertile females and are unable to establish their own colonies. Instead, they forage for food, bringing prey into their nests. Smaller army ant workers also tend to the queen’s eggs, and soldier ants defend the army ant nest.

Army ants thrive primarily in tropical areas and are common on volcanic islands and mountain heights and in vast deserts, swamps areas, lowland tropical forests, rainforests and scrub forests.

Although they usually live in humid climates, army ants can venture into agricultural environments and densely forested areas to forage for food. Army ant colonies can diminish the food sources of other animals such as birds, beetles and reptiles. As a group, army ants are capable of killing pigs, chickens, goats, snakes, lizards and other animals.

Army ants typically nest in trees above the ground but also can form a bivouac, creating a nest from the bodies of the army ants themselves. During this process, army ants use their claws and mandibles to attach themselves to one another, forming protecting walls to safeguard their queen and larvae. This structure is temporary and disassembles when the army ants mobilize.


Reproduction is the role of the colony’s queen who produces a cyclic brood of immatures. Queens are large, without wings and never leave the colony. Queen army ants will mate with multiple male ants and may produce up to 4 million eggs per month in a healthy colony

The queen’s reproductive cycle controls both migratory and stationary stages of the army ants. When army ants have collected enough food, they begin their stationary phase and create temporary nests. They remain stationary for two to four weeks, during which time the fertilized queen lays up to 30,000 eggs each day. At this point, larvae from the previous stationary stage begin to spin cocoons, becoming pupae and then adults. As the population of the colony increases, army ants once again enter the migratory stage.

The army ant queen and her colony can survive up to 20 years. However, male drones will die soon after mating with the queen, and workers survive only one year.

Signs Of An Infestation

Army ants are easily recognized by the presence of huge numbers of foraging, trailing ant workers who search for food to sustain the colony. The colony is built of the ants themselves and is observed above ground. Sometimes, army ants will get inside the home and forage for food scraps.

More Information

If you suspect army ants have invaded your property, do not delay in calling your pest management professional for advice and assistance. In addition to performing the direct pest control work needed, your pest management professional will also provide some preventive control tips for excluding ants from your home, including:

• Cleanliness. Regularly clean and remove potential food sources.

• Exclusion. Keep out ant foragers by sealing and screening places where ants can get inside to establish a new colony or forage for food. Exclusion is especially important on the foundation of your home.

• Keep mulch away from the foundation and never let your landscaping plants contact the side of the house.