Respective contributions of leader and trail during recruitment to food inTetramorium bicarinatum (Hymenoptera: Formicidae)

Summary This paper describes the food recruitment strategy of the antTetramorium bicarinatum, at both the individual and collective levels. The general organisation of recruitment used by this species during the exploitation of sucrose solutions shows similarities with group recruitment described for other species. However, our experiments demonstrate that inT. bicarinatum, the first trail laid by a recruiter during its return trip to the nest is more efficient than in other species using group recruitment, for exampleTetramorium impurum. Moreover, the efficiency of the first trail of aT. bicarinatum recruiter is comparable with that ofTapinoma erraticum, a species that uses mass recruitment. Despite the efficiency of the trail, choice experiments show that the recruited workers prefer to follow the leader rather than the first trail, suggesting the emission of a more attractive signal by the leader on its way back to the food. The function of the leader in this strategy is discussed in terms of collective decisions.