Everything is bigger in Texas, especially the massive rafts of fire ants floating in the wake of Hurricane Harvey. These aren’t your typical congregations of fire ants, either. Nature, almost comedic in its cruelty, has made it so their painful, blistering stings are much more potent than usual.
Solenopsis invicta ants, commonly known as red imported fire ants (or “spicy boys” in some circles), are native to South America but have spread throughout the southern United States, thanks to a number of adaptations that make them exceptionally well-suited to thrive in environments ranging from arid sand to literal floods.
One of their most terrifying adaptations, as Texans and horrified internet users have recently discovered, is their uncanny ability to link together and form a raft in which individual ants take turns above water. This ensures a colony’s survival in the event of a flood, and, oh yeah, it also creates floating nightmares.
“The average venom per sting delivered by S. invicta workers was around 87 percent greater, a bit short of double the dose, while rafting than when defending from the relative safety of their nests in the ground,” Kevin Haight, a research specialist at Arizona State University, tells Inverse.
Floating rafts of Solenopsis invicta fire ants are even more venomous than usual.
Haight is referring to the research he published in 2006 in the journal Insectes Sociaux, which showed that these invasive ants, known for their painful stings, become even more hazardous during flood conditions.
In an experiment, Haight compared fire ants’ venom output before and after colony rafting by using a latex dummy hand to measure venom output and sting frequency in a colony before and after he flooded it. The difference was clear, and Haight says it made a lot of sense from a survival adaptation perspective. The ant colony, he says, is never more vulnerable than it is while rafting.
“They are exposed on all sides and they cannot flee,” he wrote. “They are even potential prey for animals that would not otherwise be threats. For example, rafting colonies on ponds or rivers may make tempting targets for fish or other aquatic predators.”
One fire ant bite is painful enough, but if you wander into a whole raft of them, you could get a shitload of these pustules.
Unfortunately for humans, potential predators and clumsy bystanders don’t look any different to ants, so if you touch an ant raft, you’ll probably get stung.