Stinging Islands of Doom: A Post-Harvey Fire-Ant Refresher Course

Fire ants originally came to the U.S. from South America, but have made themselves quite at home in Texas.
Fire ants originally came to the U.S. from South America, but have made themselves quite at home in Texas. Photo by Marufish
During the deluge and flooding of Harvey, one of the unexpected horrors many people witnessed were enormous colonies of fire ants, floating on top of the floodwaters like stinging islands of doom. Stories about the floating ants gained widespread traction, with countless articles being written about the phenomenon. The photos of giant floating colonies of the biting insects were nightmare fuel, the kind of WTF, nature-gone-wild moment that made many of us wonder what other biblical plagues were coming, and how much worse were things going to get.

It turns out the ants were just doing what everyone else was doing during an extraordinary crisis: trying to do what it took to survive until they could reach dry land. Fire ants are originally from Argentina and Brazil, where they often live in the flood-prone areas near rivers. Over time they developed a survival skill of banding together into a “raft” to protect the colony from drowning. These floating islands of ants can allow the insects to ride out a flood, surviving hours or even days…long enough for the water to recede, or for them to float to dry land.

Whether this is a miracle of nature or a complete horror show, I'll let others decide; needless to say, it's a really bad idea to, say, swim into a colony of thousands of floating fire ants. That aside, the floating ants didn't pose much of a real threat to most people, and just served as a reminder that ants are nature’s little badasses and can do lots of amazing things.

For instance, a fire ant colony can be made up of 200,000 to 500,000 ants, with multiple queens. These colonies can grow incredibly fast, and even though our winters typically kill 80 to 90 percent of the ants in them, their numbers will explode as the weather gets warmer. While fire ants are usually more of a painful nuisance than an actual danger to human beings, their stings do cause around 20 deaths per year.

Although fire ants are originally from South America, there are presently more of them in North America than in their native countries. The floating islands of ants were creepy and made good press, but realistically there are a lot more of them throughout the region under normal conditions. While the floating ant rafts were impressive in size, it's possible that Harvey’s flooding actually killed off a lot of the area’s fire-ant population, although the survivors’ fast reproductive cycle will likely have their population rebounding quickly.

In Houston and the surrounding area, fire ants are probably in the Top 10 on most lists of area pests. Only mosquitos seem worse, and anyone who's ever had a few dozen fire ants swarm up their leg and bite, knows the experience is a painful and memorable one. Fortunately, though, the floating ant rafts were just a rarely seen survival strategy that falls within normal fire-ant behavior, and not some new and terrifying sign that ants are evolving and will soon be our overlords.

Or will they?
KEEP THE HOUSTON PRESS FREE... Since we started the Houston Press, it has been defined as the free, independent voice of Houston, and we'd like to keep it that way. With local media under siege, it's more important than ever for us to rally support behind funding our local journalism. You can help by participating in our "I Support" program, allowing us to keep offering readers access to our incisive coverage of local news, food and culture with no paywalls.
Chris Lane is a contributing writer who enjoys covering art, music, pop culture, and social issues.