AUBURN, Ala.— Tropical storm Cindy promises to bring heavy rains to Alabama and possibly flash flooding. When floodwaters come, humans are not the only ones looking for dry ground. In areas infested with red imported fire ants, these ants and their colonies can present a potentially serious medical threat to people and animals during and after a flood.
Flood Waters and Fire Ants
Floodwaters will not kill fire ants. Instead their colonies will emerge from the soil, form a loose ball, float and flow with the water until reaching a dry area or object.
Floating colonies can look like ribbons, streamers or a ball of ants floating on the water. These amoeba-like masses contain all of the colonies’ members—worker ants, brood (eggs, larvae, pupae), winged reproductive males and females, and queen ants.
When flood waters begin to recede, floating fire ant colonies will clamber on to anything they come in contact with. Fire ants are attracted to anything with the potential to provide shelter until a mound can be reestablished in the soil. Debris piles and piles of items from flooded homes are very inviting. Ant colonies encountered during a flood must be dealt with quickly.
Fire Ants During Flooding
During the flood, there are several tips Alabama Extension entomologists recommend.
- Avoid contact with floating masses of fire ants.
- If you are in a rowboat, do not touch the ants with oars.
- When working in floodwaters, dress appropriately if possible. Rubber boots, rain gear and cuffed gloves can help prevent ants from reaching the skin.
- If ants contact the skin, they will sting. Remove ants immediately by rubbing them off. Ants will only cling to the skin if submerged. Even a high-pressure water spray may not dislodge them. However, a spray of diluted, biodegradable dishwashing liquid may help immobilize and drown them.
- When returning to flooded structures, floating ant masses are occasionally encountered—even indoors.
Fire Ants After the Flood
Fire ants can be under anything. When debris is picked up, pay attention to what is on, under, or in it—especially if the debris has been sitting in the area for several days.
Protect yourself. Wear gloves, long-sleeved shirts, long pants, socks and shoes. Consider spraying insect repellent onto your shoes and lower pants legs. Insect repellent may deter foraging fire ants from climbing onto the legs, but it may not repel ants defending their colony.
If fire ants are seen in a pile of debris that must be handled, use a shovel or another tool to avoid ant contact. Consider treating the pile with a fast-acting household or lawn and garden insecticide. Use erosol spray products containing pyrethrins or pyrethrun derivatives that are labeled for ant use,and have a quick knockdown. These sprays also break down quickly.
Spray as many of the ants as possible. Keep in mind insecticides can be toxic to aquatic organisms. Spray surfaces and cracks of infested objects and debris. Then come back after the product has had time to act.
Fire ant bait products should not be used at this time because they are slow-acting. Flooded mounds will be disorganized and worker ants will not be foraging for food.
The Emergency Handbook brings together recommendations from national emergency response agencies and major universities into one easy-to-understand, interactive reference. It also addresses nearly 50 disaster preparation and recovery topics in four broad categories, including: People and Pets, Home and Business, Landscape and Garden, and Farms and Livestock.
Featured image by Dr. Bart Drees