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The foraging strategy of a colony of social insects, e.g. ants, is made up of simple individual decisions being influenced by a series of factors like climatic conditions, properties and availability of food and competitive context. We studied the use of space, foraging success and competitive relationships in Formica cinerea around its nests in field conditions in the absence and in the presence of artificial food sources on sand dunes in Finland. Generally, the abundance of foragers was low around colonies. Sources in close proximity were mostly discovered. However, the fact that distant sources were sometimes preferred over discovered close sources during mass exploitation appeared to confer a certain sub-optimality upon the foraging strategy of the species. The use of baits allowed us to analyse the species’ competitive position as well. Generally, rivals could dominate sources far from the nest of E cinerea, thus a facultative inhibition zone was established around the studied colonies. Although, mostly dominant in contests, E cinerea could give up food sources to rivals if these were already gathered on the bait. The mixture of submissive and aggressive features, which characterise E cinerea allows this species to adapt to the current competitive context and the availability of food sources.