Army ants get their name from their tendency to run around in big raiding groups, feeding on other ants and insects.
There are over 200 different species of army ants and they are normally found in the tropical rainforests of South America. One of the most studied of those species is Eciton burchellii. These ants rest in a bivouac, which is a temporary nest made up of ants. The queen and the colony find their resting spot in the center of the nest of ants before moving at night in search of its next location.
When the day begins, these ants spread out and raid almost anything in their way. They sometimes travel over 200 yards when they’re raiding. The lead worker ants leave a chemical trail for the others to follow. Smaller worker ants lead the colony, while the other ants protect their borders. When they are in need of a new food source, the entire colony may transfer to a new nesting site.
What Can an Army Ant Eat?
As mentioned before, army ants feed on other ants and insects, including beetles many times their size. They can even feed on some smaller animals like frogs, snakes and lizards. They have large mandibles that act like scissors that they to use to slice their prey. While slicing up their victim, they spread a dissolving acid that is used to melt down flesh and muscles into a liquid matter. When the colony is moving out to forage, if the workers find food, they'll dispatch the information through a scent back to the nest, enabling the colony to mobilize and get ready to move.
The only defense against an army ant attack is staying still. This is because army ants are nearly blind, so they rely on light and darkness from movement to detect prey.
Are Army Ants Harmful to Humans?
Though people living in the United States don’t really have to worry about army ants since they aren’t very common, should you visit a rainforest in South America, just know that you aren’t a usual prey for army ants. And minus a potentially painful bite, army ants don’t pose much harm to humans.
Established colonies can hold between 150 thousand to 2 million individual army ants.
Unlike most insect queens, queen army ants do not have wings. But what’s even stranger is the fact that these queens can change size when moving to a new nest location.
The minor army ant workers can measure up to 0.25 inches in length. They are very dark brown to black ants with orange colored abdomens. Major army ants can measure up to 0.5 inches in length. They have pale orange heads, dark orange legs and large, dark mandibles.