Color drawing of the red imported
fire ant. By Joe McGown.
Facts
- Fire ants first entered the United States about 1918, near Mobile,
Alabama.
- Fire ants reached Mississippi around 1930.
- Fire ants now occur over much of the Southeast. [USDA
fire ant quarantine map]
- Northern migration of fire ants will likely be limited by cold—winter
temperatures that freeze the soil deeply enough to affect overwintering
colonies.
- There are two species of fire ants in the state. Red imported fire
ants are the most common, but some areas have black imported fire ants,
or hybrids of these two species. These two species are similar in biology
and behavior.
- Fire ants are social insects that nest in the soil in large
colonies that contain tens of thousands to more than 200,000
ants.
- Most of the ants in a fire ant colony are infertile, female
workers.
- Worker fire ants vary in size,
but all are capable of stinging.
- Usually there is only one queen per colony. The queen
lays the eggs.
- Fire ants have a complete life cycle. The eggs hatch into legless
larvae, which develop into pupae and
ultimately become adults.
- Fire ants feed on a wide range of foods, including
insects, honeydew, plant nectar,
seeds, fruit and animal carcasses. They especially like foods
high in fat.
- Foraging workers exit the mound through underground
tunnels that radiate away from the mound, exiting to the surface
five to 25 feet away from
the mound.
- Adult fire ants are incapable of swallowing solid food. They have
to carry it back to the mound.
- Solid food is fed to the larger
larvae, which chew and digest it and regurgitate it in liquid
form.
- Liquid food is passed from the larvae back to the workers and then
shared with all ants in the colony.
- Fire ants spread by swarming.
Unmated, winged reproductive male and female ants exit the mound in
mass, fly into the air and mate while airborne.
- Newly mated fire ant queens fall
back to the ground within a few hundred yards to a few miles of the
mound from which they emerged, shed
their wings and attempt to start new colonies.
- At first the new queen is ‘on her own’. She lays a few eggs that
eventually become small workers. These first workers then help care
for their younger sisters and the colony begins to grow.
- It takes several months for a colony to get large enough to build
a mound large enough to be
noticed in the average home lawn.
- For every large mound in a lawn there are usually many younger colonies
that are still too small to produce visible mounds.
- Once a young fire ant colony is well established and has a few thousand
workers, it can quickly develop into a mature
colony containing tens of thousands of ants.
- Small colonies develop into large colonies especially quickly if
there are no bigger colonies nearby to compete with them.
Contact
Dr. Blake Layton, Extension Entomology Specialist
Department of Entomology, Mississippi State University
Phone: (662) 325-2085
Email: blayton@entomology.msstate.edu