Which ant species builds rafts to survive floods?

The ant species known for building rafts to survive floods is the fire ant, especially the red imported fire ant, Solenopsis invicta. When rising water threatens a colony, thousands of workers link their bodies together into a buoyant living structure.

The ants’ hydrophobic bodies help repel water, while their interlocked legs and jaws create a flexible raft. The queen and brood are carried within or above the mass, keeping the colony’s reproductive center protected while the raft drifts toward dry ground. The structure can flex and roll with waves instead of breaking apart like a rigid object.

Fire-ant rafts are not permanent nests. They are emergency flood-survival structures, and colonies may remain afloat for many days. Studies have found that the ants redistribute themselves as conditions change, helping the raft stay stable even when exposed to currents or predators.

A common misconception is that one ant floats like a tiny boat. The remarkable behavior depends on cooperation: individual ants are joined into a waterproof colony-scale raft.