5 crazy facts about crazy ants

May 2, 2018, 9:19 a.m.
Tawny Crazy Ant
Photo: Bentleypkt/Wikipedia

These invasive 1/8-inch ants are taking over the South at an insane rate. Here are a few useful things to know about your new neighbors:

1. Crazy ants are an invasive species.

Originally from South America, the tawny crazy ant — also called the raspberry crazy ant — showed up in the southern United States in 2002 or perhaps earlier. Their presence is more than just an annoyance. Because they feed on small insects and arthropods, they're gobbling up food that other species like birds and reptiles rely on. Their presence will trickle up the food chain with currently unknown ramifications — and there doesn’t seem to be much that can stop them.

Not only do they have few natural threats, but they are tough for human exterminators to wipe out. "These ants are difficult to control because they are ready to abandon their homes and find new ones at a moment's notice, as when insecticides or poison baits are applied," reports Slate. Their colonies also have multiple queens, allowing them to reproduce quickly and bounce back from extermination attempts.

2. Crazy ants are winning the turf war with fire ants thanks to a built-in defense mechanism.

Crazy ants can save themselves from the venom of fire ants by grooming themselves with an antidote they secrete from a special gland. Instead of a stinger, they have a fire ant anti-venom gland! The substance is formic acid, and it's use is two-fold: the same antidote that they use to nullify venom on themselves is used as a chemical weapon against competitors. With this built-in dual-purpose chemical, it seems crazy ants are unbeatable.

3. The second secret weapon crazy ants have is sheer volume.

Crazy ants' connected colonies can form huge populations. Without natural competitors keeping them in check, in the U.S. they can "attain densities up to 100 times as great as all other ants in the area combined," according to Ed LeBrun of The University of Texas at Austin.

As Scientific American reports, "Teeming out of electrical outlets and short-circuiting electronics, the tiny reddish-brown crazy ants have been making headlines as their numbers climb in the southeastern U.S. In some locales they can be so tightly packed together they are initially mistaken for dirt. Then they move."

These colonies of crazy ants can advance as far as 200 meters per year. Of course, that’s advancing on their own — unfortunately, people are inadvertently helping them advance as well. Crazy ant nests can be found in potted plants and other mobile "homes" that people pack up and shift around. So, crazy ants are now popping up all over the Southeast, especially in Florida and Texas, far more rapidly than if left to their own devices.

4. Speaking of devices, crazy ants are known for shorting out electronics.

They are attracted to gadgets such as air conditioning units, computers and other devices in their search for new cavities to build nests. But that’ just the start. Live Science reports, "When the crazy ants enter these devices, their bodies can create connections between electrical contacts, which can lead the circuits to short out and electrocute the ants. This causes them to release an alarm pheromone, a scent ants use to communicate that they are 'under attack,' likely attracting the ants' kin to come and fight, LeBrun said. This creates a vicious cycle that can leave appliances broken and full of dead (and angry) ants."

5. Crazy ants are so named because they have a fast and erratic way of moving when foraging for food.
Their unpredictable movement looks… well, crazy.

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