Foraging patterns and strategies in an Australian desert ant

The Australian desert ant Melophorus bagoti (Formicidae) is a thermophilic, solitary foraging ant that inhabits the semi-arid regions of Australia. In recent years, it has become a model species for the study of navigation. However, its ecological traits are not well understood, especially on the level of the entire colony. Here, we investigated this species daily activity schedule and diet composition, and examined its foraging behaviour. Foraging activity is confined to a window of roughly 50-70°C soil surface temperature, and foragers reacted quickly to temperature changes. Consequently, the pattern of daily outbound traffic during summer is unimodal on warm days and bimodal on very hot days. Foragers are opportunistic scavengers; dead insects make up a large proportion of food items, but grass seeds are also occasionally brought back to the nest in large amounts. Diet composition changes with the seasonal availability of certain food groups. Melophorus bagoti foragers have the ability to recruit nestmates to profitable food sources. Recruitment seems to function without the use of pheromone trails, but the exact mechanism requires further investigation.