Massive colonies or “islands” of fire ants are being spotted floating atop Hurricane Florence floodwaters in North and South Carolina.
The colonies consist of “aggressive” ants that pile on top of each other to create an island on top of water — and they can be potentially dangerous.
According to the South Carolina Department of Health and Environmental Control, fire ant stings are “mild irritants” to most people. However, about one in 200 people are seriously allergic to the bites. Serious reactions can result in hives, facial swelling, and difficulty breathing. In rare cases, it can lead to nausea, sweating, dizziness or chest pain.
“Death may occur if rapid treatment is not available,” the organization explains on its website.
The phenomenon is not new — the ants are often spotted following storms that cause flooding. And getting rid of them can be hard in such cases.
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“During times of high water or soaked ground, the usual treatments for fire ants are not practical,” the website explains. “People should be alert for fire ants during clean up from a disaster and wear protective clothing.”
The ants garnered attention following 2017’s Hurricane Harvey as well, with several people posting videos of the ants on social media.
Studies have warned those living in areas where there is flooding to watch out for the ants, especially if they are using boats for transportation.
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A 2012 study published in the Communicative and Integrative Biology journal said that the colonies can have more than 100,000 ants.
Research by the Texas A&M AgriLife Extension Service explained how individuals should act if they do encounter the ants while boating.
“Avoid contact with floating mats of fire ants. If you are in a row boat, do not touch the ants with the oars since they can “climb aboard” via the oars. Occasionally, floating ant masses are encountered even indoors in flooded structures,” warns an article published by the organization.
It added that the ants can “cling to the skin” and even high-pressure water will not remove them.
“However, a spray made of diluted biodegradable dishwashing liquid may help immobilize and drown them,” it read.