White footed house ant (Technomyrmex spp.) in Australia

Invasive

White footed house ants are thought to be present across Australia, with the exception of South Australia, Tasmania and northern Western Australia. Getting confirmed identification is always a challenge but T. difficilis has been confirmed in northern Queensland and the Northern Territory and T. albipes has been confirmed in New South Wales

White footed house ants do not nest in the soil – they nest at or above ground level. In buildings they will commonly nest in wall cavities and roof voids.

White footed house ants can form massive colonies of up to several million ants. In these large colonies around half the colony is made of intercastes – secondary female reproductive. There is a nuptial flight each year and after mating on the wing, successful new queens will start a new colony. Over time, as the colony grows the intercastes eventually replace the original queen. These intercastes can also create new nests by budding (leaving the nest will a small number of workers and brood).

Colour: Dark brown to black with white or pale ends to the legs
Size: 2.5 – 3.0 mm
Nodes on petiole: No obvious node

Although omnivorous, black house ants have a strong preference for sugar and will often be seen trailing into trees to collect honey dew from sap feeding insects.

• White footed house ants can create significant and long lasting trails, which can remain in place for several months. The trails will often follow the edges of structures.
• Unlike most ants, white footed house ants are not thought to exhibit trophallaxis – they do not share their food with their nest mates. Instead sterile workers lay tropic eggs – special ‘food’ eggs which are fed to larvae and non-foraging nest mates
• Sometimes groups of workers are observed remaining motionless on walls and other surfaces. The reason for the behaviour is unknown

• White footed house ants do not bite or sting

White footed house ants commonly access buildings through adjacent vegetation. Clearing vegetation from around the perimeter of the building and trimming back any branches overhanging or touching the roof will help.

Can sometimes be confused with the black house ant and Argentine ant.