The Pharaoh ant colony consists of queens, males, workers, and immature stages (eggs, larvae, pre-pupae, and pupae). Nesting occurs in inaccessible, warm (80 to 86°F), humid (80%) areas near sources of food and/or water, such as in wall voids. The size of the colony tends to be large but can vary from a few dozen to several thousand or even several hundred thousand individuals. Approximately 38 days are required for development of workers from egg to adult.

Mating takes place in the nest, and no swarms are known to occur. Males and queens usually take 42 days to develop from egg to adult. The males are the same size as the workers (2 mm), are black in color and have straight, not elbowed, antennae. Males are not often found in the colony. The queens are about 4 mm long and are slightly darker than the workers. Queens can produce 400 or more eggs in batches of 10 to 12. Queens can live four to 12 months, while males die within three to five weeks after mating.

Part of the success and persistence of this ant undoubtedly relates to the budding or splitting habits of the colonies. Numerous daughter colonies are produced when a queen and a few workers break off from the mother colony. Even in the absence of a queen, workers can develop a queen from the brood, which is transported from the mother colony. In large colonies there may be as many as several hundred reproductive females

Control of Pharaoh ants is difficult, due to their nesting in inaccessible areas. Treatment must be thorough and complete at all nesting sites, as well as the foraging area. Thus, treatment must include walls, ceilings, floor voids, and electrical wall outlets. Baits are now the preferred method of control for Pharaoh ants and several baits (insecticides) are labeled for indoor ant control. A Pharaoh ant infestation of a multifamily building requires treatment of the entire building to control the infestation. Ants nesting on the outside may be controlled by also using a perimeter barrier treatment.

Prevention Tips

Control of Pharaoh ants is difficult, due to their nesting in inaccessible areas.

Treatment must be thorough and complete at all nesting sites, as well as the foraging area. 

Treatment must include walls, ceilings, floor voids, and electrical wall outlets.

Baits are now the preferred method of control for Pharaoh ants.