Big-headed ants (Pheidole megacephala) are named for their soldier caste, which has an oversized head relative to its body. Workers are small (1.5–3mm) and reddish-brown. In Davenport, they are most commonly noticed as trails along sidewalks, driveways, and the base of exterior walls. They nest in soil and can displace other ant species due to aggressive colony growth.
Big-headed ants are frequently mistaken for fire ants when found outdoors, but they do not build dome-shaped mounds — they create loose soil disturbances or nest under objects on the ground. They forage for protein and sweet food sources, trailing both outdoors and occasionally indoors through foundation cracks. Because colonies are often large and spread across extensive underground networks, surface-level treatment alone is insufficient. Targeted granular bait applied to foraging trails is the most effective control method, combined with perimeter barrier treatment to prevent interior entry.