Pavement Ants measure approximately 1/3 cm in length and have reddish-brown to black bodies, pale legs, and antennae. These ants are found throughout the Pacific Northwest. Pavement ants earned their name because they nest in cracks in driveways and under sidewalks, piling the resulting dirt in a mound on top of the pavement.
They also dwell on the undersides of logs, bricks, stones, patio blocks, and boards. They may also nest under mulching or open soil close to building foundations but rarely nest indoors.
They undergo complete metamorphosis, passing through the egg, larval, and pupal stages before becoming mature adults.
A typical nest of these ants includes multiple queens and numerous workers. A queen establishes a new colony of pavement ants by laying eggs. Pavement worker ants then tend the queen’s brood until they develop into adults. During their development, broods are transferred from location to protect them from fluctuations in moisture and temperature. I have seen them many times, hauling the eggs in a long line from one area to another.
Pavement ants will feed on a wide variety of foods, including live and dead insects, meat, grease, seeds, and honeydew from aphids. They prefer to eat greasy foods and can eat most foods consumed by humans. They forage for food up to thirty feet from their colonies and set up trails to food sources from their nests. Pavement ant workers enter houses to forage and can become a nuisance when large groups infest your home.
They will set up temporary nests in your home from which they forage, and then other ants return to the main nest with their gatherings. We have had them set up these nests in the strangest places, like clock radios, baseboard heating units, inside telephones, and other strange spots.