Fire Ants Survive South Carolina Floods by Forming Ant Islands
Ants have some of the most ingenious survival strategies, even resisting natural disasters. With massive rainfall that has recently caused flooding in areas of North and South Carolina, Fire Ants have had an opportunity to show how hardy they truly are.
Forming the Raft
Fire Ants’ bodies are naturally hydrophobic; this means that they repel water to some degree. As long as the water has surface tension, a Fire Ant will be somewhat buoyant. This characteristic is enhanced when they link their bodies together, by having the effect of creating a lightweight, waterproof fabric to stretch across the surface of the water. These “Ant Islands” have been observed and filmed in flooded areas.
As long as the raft is not pulled apart or the surface tension of the water disrupted, these rafts can survive afloat for days and even weeks. In videos, you can see the ants clustering in the middle to protect their queen(s) and eggs. This raft-building is a common survival strategy wherever Fire Ants face flood conditions. Even the ants on the underside and edge can survive thanks to their bodies which can use bubbles in water to help support floatation and provide air.
A Sturdy Ship
It is interesting to consider how the ants organize themselves in the way they do. Ants at the edge of these islands are observed to be held in place by their adjacent brethren, raising the question of just how ‘cooperative’ this behavior is.
These rafts are so elastic and buoyant that they can endure being prodded by a solid object such as a stick or twig. The ants can efficiently assemble into their positions in less than 100 seconds. Despite its durability, even a small amount of soap introduced to the water where ants are floating will immediately cause them to sink, because of the diminished surface tension.
Despite the annoyance colonies can provide and the painful sting they can cause, you have to respect the Fire Ant’s amazing survivability.