Brachymyrmex patagonicus, or the dark rover ant, is a non-native ant species that has become well established in the southeastern states and urban areas of the southwest. Due to the extremely small size of dark rover ants, as well as their resemblance to closely related ant species that are already common in the southern US, experts are unsure as to when and how these ant pests were introduced into the country. The dark rover ant has become a major nuisance pest in the US, and they established an abundant presence in San Antonio around 15 years ago where pest control professionals often struggle to eliminate indoor infestations.
During the 2010s, pest control professionals and University Extension entomologists from Texas and the southeastern states experienced an abrupt influx of calls from homeowners complaining about these ant pests. However, experts were not able to offer much help with dark rover ant pest issues given their lack of knowledge concerning the pest behaviors of this understudied ant species. Both swarming alates and foraging workers of this species invade homes where workers frequently establish nests within concealed areas, such as wall voids, beneath floorboards and in crawl spaces. Swarming alates are particularly annoying to homeowners due to their habit of swarming around porch lights and indoor light sources.
Dark rover ants establish colonies in the soil surrounding tree stumps, beneath leaf litter, pavement, concrete slabs and in mulch surrounding the foundation of residential homes where they easily gain access indoors. These ant pests prefer to establish colonies near urban and suburban regions, and they seem to have no problem establishing multiple satellite nests indoors. However, workers may also travel indoors from colonies located in yards, but given the near-microscopic 1 to 2 mm size of workers, homeowners often fail to notice the ants.
Those who have experienced dark rover ant infestations state that the pests are most abundant in bathrooms and kitchens where moisture levels are relatively high, and homes located on irrigated lawns in arid regions are particularly vulnerable to infestations. These ants are rapidly expanding their habitat in the southern states, and infestation rates are increasing in San Antonio. Given the dark rover ants need for high moisture environments, taking measures to eliminate indoor moisture will help to prevent infestations.
Have you ever experienced rover ant pest issues within your home?