The structure of a fire ant nest
The structure of a fire ant nest is unique. While comparable to other ant nests, it stands out from the rest. Fire ants are attracted naturally to warm, damp places. They nest depending on this variable only. They are most active in building during the spring and fall, when the weather is damp and warm. During winter, they will burrow closer to warm patches in the soil. However, in Summer, they will burrow towards cooler patches of soil, to maintain a balance. They are attracted to sites with lots of metal and especially concrete, which they will build nests on or above.
One of the major defining features of a fire ant’s nest is its hilltop. The top of the nest will be like a cone, oblong in nature. However, unlike most ant nest tops, the fire ant will have multiple exits, none of which are on the top.
The material used to build the nest will vary depending on what the soil is composed of. Its structure also depends on the age and needs of the nest. A large colony can make a nest that has a hilltop of half a foot high, or higher, and have main and side tunnels that stretch up to over 130 feet from the main entrance/exit! The depth of the nest is usually a few inches, again dependent on the need for the colony. The queen will be moved throughout the day, along with the eggs, to ensure that she is safe from unfavorable conditions. This means, during the cool spring days, she might only be moved once from surface to lower ground around noon for heat adjustment, but in summer, she might travel much deeper into the ground to stay cool.
There are a few different rooms. While the ‘trash’ of the colony is usually kept outside the nest, it can be housed in a room during unfavorable conditions in piles known as “middens”. These rooms are emptied when possible. Directly beneath the surface would be where the ants would ‘eat’. Food would be stored close to this room. A room for general congregation/rest or sleep would be kept beneath this storage room. Keeping in mind that the queen may be moved often throughout the day, on an average condition set, she would be kept lateral from this room in a room of her own. Beneath hers, the larvae and eggs would be kept. The main tunnels could extend for many many feet in any direction from this main buldge of rooms. These tunnels could connect to water tables or warmer/cooler soils. If conditions become too harsh (pesticides, for example) the queen and possibly the whole colony could be moved to a different portion along the main tunnel to avoid mass death.
