Foraging preferences of ants on a heterogeneous Brazilian sandy shore habitat

1. Ants may select their food in response to nutritional needs of the colony and forage in a way that optimises a complementary nutrition. Even though resource availability is known to affect ant colony and individual health, there is still no study that has investigated the plastic preferences of ants according to spatial resource availability in naturally heterogeneous conditions. 2. Beaches are great biomes to test spatial foraging preference because a complete absence of nectaries can be found. Dorymyrmex nigra Pergande 1896 was found inhabiting a beach in southeastern Brazil, in which nectar sources are heterogeneously distributed. This study tested whether the foraging preference to sugar baits depended on the availability of nectar sources surrounding the nests. 3. We found that more D. nigra workers foraged on sugar baits when the colonies lacked naturally occurring nectar in their vicinity compared with colonies with abundant nectar nearby. 4. These results show that the foraging preference of ants depends upon resource availability. This is the first study to use a natural mosaic of resource availability to show that resource preference of ants is plastic and varies spatially.