As if Houston didn't have enough problems…
Fire ant rafts can look like ribbons, a mat or an actual “ball” of ants floating on the water containing the entire colony – worker ants, eggs, larvae, pupae, winged males and females and queen ants. These rafts of fire ants float until they come into contact with something to adhere to such as a tree, a mailbox, a garage, a house, etc. And that’s when the danger comes, when people come into contact with the ants.
http://www.sfgate.com/news/article/Floating-fire-ants-Houston-Hurricane-Harvey-12083209.php
Victims of Hurricane Harvey’s devastating flooding in Houston and Southeast Texas have a new threat to worry about: floating colonies of aggressive fire ants.