Invasive Ant Species

The most common ant around the house and garden is the Argentine Ant, an invasive species from (yes you guessed right)…. Argentina. In the late 1890´s, coffee ships from South America brought stow-a-way ants inside their cargo into the port of New Orleans. Favoring California´s mediterranean environment, Argentine ants have made their home here, and like others “from afar,” have decided to stay.

Argentine ant (Linepithema humile) tending an aphid.

The Argentine Ant isn´t the only ant that traveled from South America into the states, it´s cousin, the Red Imported Fire Ant (Solenopsis invicta), has also invaded our shores.

Fire ants avoiding an enemy phorid fly.

Red Imported Fire Ants

The Red Imported Fire Ant has a venomous, painful sting; it stings not only people but animals as well. Fire ants have spread across much of the South, feeding on crops in 11 states. In battle with Argentine ants, fire ants will win 80% of the time. They have very few natural enemies.

Phorid Flies – Natural Enemy of Red Imported Fire Ants

There is however, one natural enemy of the fire ant that scientists at the U. S. Agricultural Research Service Center are hoping to utilize in order to protect American
crops — the South American Phorid Fly (Megaselia scalaris).

Parasitic South American phorid fly attempting to lay an egg into a fire ant worker.

The female phorid fly deposits an egg in the fire ant´s body which then turns into a maggot that moves through the body, into the neck and eats the tissue — thereby beheading the fire ant. I have refrained from showing a picture of a beheaded fire ant and will leave that to your imagination.

Two Red Ants Fighting

War of the Ant Worlds

Ants have been around about a hundred million years — since the age of the dinosaurs. Like humans, ants display behavioral characteristics such as loyalty (to the colony), consistant communication, the breaking of bread together, grooming one another, and taking care of their young. Ants also protect their “country” by implementing homeland security tactics of deception, skilled surveillance and mass assaults – often in the name of war.

Ant carrying a wounded comrade.

Ant Battles and War Tactics

While engaging in battle to keep and gain territorial rights, some ants will actually fight by dropping stones on their enemies. Others turn their adversaries into slave labor. Argentine ants use the following special tactic, regardless of the size of the enemy: They surround their enemy keeping well away from its dangerous mandibles, then suddenly, one ant rushes in and grabs the enemy´s leg. The other ants quickly follow and bite off the legs leaving the enemy ant immobilized, then they continue biting to completely dismember their victim.

Group of Argentine ants.

Invasive Ants vs. Native Ants

While various species of ants are battling among themselves, slowly, both the Argentine and the Red Imported Fire Ant are invading the world. These ants have not only consumed and displaced California´s native ants but have also caused the decline of some native species such as the coast horned lizard. The coast horned lizard´s primary food source has always been the larger, native ants; these include seed-harvesting, honeypot, carpenter, and native fire ants. Pest management of invading Argentine and red imported fire ants and their supercolonies is becoming increasingly important for humans — and California´s native species.

Native Red Seed-Harvester Ant (Pogonomyrmex barbatus)

Lonesome Scout

Ok, I give, here is a picture of the beheaded fire ant.

Beheaded Red Imported Fire Ant

Article by Donna Walker; each photo is credited with the source and/or photographer within the image.

The Dominance of Ants References

USDA – United States Department of Agricultural Research Service

Farb, Peter, & Editors of Time Life Books, (1977). The Insects. Time-Life Books Inc., Alexandria, Virginia.

Holldobler, B., & Wilson, E., (1995). Journey to the Ants. Cambridge, Massachusetts, The Belknap Press of Harvard University Press.

Tagged: Ant Behaviors and Abilities