Houston residents dealing with rising floodwaters from Hurricane Harvey have one more threat to consider: floating islands of fire ants.

On Twitter, several journalists have captured images and videos of the ants floating along floodwaters in Houston. The ant colonies band together and form on the surface of the water.

The reactions on Twitter are a mix of awe about nature and terror over a giant island of fire ants potentially floating your way.

The colonies of floating fire ants are also very dangerous. In a 2015 interview, Tim Davis, an entomologist and Clemson University senior extension agent, said the floating technique by fire ants has been used for ages to escape flooding, forming these islands in less than two minutes.

“If the water rises, they kind of all grab a hold of each other, and they can do this for several days, until they reach higher ground,” Davis said.

Similar floating ant colonies were found in Alabama and South Carolina following flooding in both regions.

Davis advised people to stay out of the flood waters and avoid the masses of ants at all cost. “If one of those rafts comes in contact with you, or you try to break it apart, it will likely disperse and crawl up you."

Follow Brett Molina on Twitter: @brettmolina23.