Tawny raspberry crazy ants (Nylanderia fulva)

Nostalgic Days

Do you miss the days when all you had to worry about when cutting the grass was a few painful blisters from those persistent fire ants? No?  Well, just wait a bit and you might.  The new ant invasion now spreading throughout Texas and the Southeast arrived sometime in the last two decades and, like the fire ant, has a thing for nesting in electrical boxes, drywall, and any other space they feel comfortable crawling into. Please welcome the crazy ants.

Tawny raspberry crazy ants (Nylanderia fulva)
Tawny raspberry crazy ants (Nylanderia fulva)

A New Invader: Crazy Ants

The tawny raspberry crazy ants (Nylanderia fulvaant) are spreading to North Texas from southern and central Texas.  Austin, still under the control of the fire ant (Solenopsis invicta), is now beginning to bow to the new invader.  I found a colony of crazy ants in my backyard last summer.  It was the first time I had seen them so close to my home.  Prior to then, the closest colony I found was more than a mile away.  They don’t seem to have spread too far past my yard, so perhaps my yard is the invasion front.  If true, that means I have the pleasure of watching a war play out in my backyard, between two aggressive ant species transplanted from South America.

The Best of the Worst

What is it with South American ant species that makes them such aggressive invaders?  Fire ants arrived in the United States sometime in the 1930’s, and have spread all over the southeast, as far west as New Mexico and Arizona.  The fire ant wreaks havoc by building huge mounds populated with thousands of sting-happy ants.  The slightest disturbance of their nests results in an outpouring of enraged, six-legged creatures looking for a fight.  Fire ants also have a nasty habit of swarming your appendages, waiting for a pheromone signal, and all stinging at once.  Synchronized stinging is their forte.  Worst yet, fire ants tend to bite down on your soft tissues, inject a small amount of venom, twirl a bit, and repeat.  So the sting frequently shows up as a circular eruption of pustules.   What could possibly compete with such an aggressive ant species? Well, the crazy ant of course.  Named for its erratic and unpredictable movements, the crazy ant is a more recent traveler and seems to be replacing fire ants in areas they land.  Believe it or not, they are more aggressive than fire ants.  That’s right, they kill fire ants.  The fire ants still attack and use their stinging toxins against the crazy ant, but the crazy ants have a way to neutralize the fire ant venom.  By coating themselves with formic acid, they escape the fire ants wrath, which is so effective against almost everything else.

Silver Lining?

On the positive side, crazy ant bites are not nearly as memorable as the itchy, lingering pain from fire ants stings – crazy ants don’t sting but instead pump formic acid from their abdomen.  They are a nuisance because they have super large colonies that are known to take up residence in any available nook and cranny.  Like fire ants, crazy ant nests can grow very large because they are polygyne, meaning there may be several queens in one colony laying eggs 24/7.  They are as comfortable outside in the soil as they are nesting in you big screen TV, radio, walls, electrical boxes, and anything else expensive.  They are also known to swarm if one of their own is injured.  So crushing them brings reinforcements to the rescue.  Unfortunately, once they arrive, they tend to stay.

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Invasive Ants

Tawny (Rasberry) Crazy Ant, Nylanderia fulva

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