Types of Ants :: Thief Ants :: Printer-Friendly Version
Ant Origin & Distribution
Thief ants are a group of closely related native ant species that are common across the United States. Although they may occur throughout most of the country, they may not always be considered a pest in certain areas.
Ant Identification
Thief ant workers are small, pale yellow to dark brown ants that are all the same size-approximately 1/16" in length. The queens are larger at 1/4" in length. These ants can be seen foraging in trails with other workers from the colony. They can be easily confused with pharaoh ants, other very small ants sometimes found in structures. A pest control professional or a county or state extension agent may be needed to help make a positive identification.
Ant Biology
Thief ants are aptly named as they will commonly nest near or even within the nests of other species of ants. From these vantage points they can steal both food and the immature brood ants (larvae and pupae) from the other ant species. Outside, thief ant nests can be found in open soil or under landscaping, pots, boards, bricks, stones, trash, wood, or in tree cavities. Inside structures, their nests can be found in small cracks, crevices and in woodwork and masonry. Thief ants can spread by swarming through mating flights. Colonies may have multiple mating flights in a year. They can also spread by splitting or "budding" a present colony into two or more separate colonies without using a mating flight.
Ant Habits
Thief ants may be seen trailing near doors and windows. To gain access to buildings, they will use tree branches and shrubs against the buildings to climb onto structures. Upon gaining access, thief ant scouts will wander within the structure looking for food. Once the food source is located, thief ants will establish trails to the resource. They can be found inside closets and cabinets, along baseboards, along sinks and on windowsills and walls. These ants show a preference for high protein foods such as larvae and eggs of other ants, dead insects, dead rodents and various seeds. They also feed on honeydew (the sweet insect secretions produced by plant feeding insects), other sweets, fruits, breads, animal fats, oils, nuts and dairy products. Since thief ants are so small, they are easily able to enter many packaged foods.
Ant Control
If you think you might have a thief ant infestation in your home, it's imperative that you contact a certified and licensed pest control professional
to inspect the situation and confirm identification. Experts will advise against do-it-yourself options, as it is much more efficient and cost-effective to have a trained set of eyes identify the correct ant species and recommend effective treatment options specific to an individual infestation. Improper do-it-yourself options may result in killing a few ants, while the rest of the colony simply relocates to other areas around and inside the structure.