Feeding and emigration of the ant Tapinoma erraticum (Formicidae Dolichoderinae). Experimental analysis of the use of...

Visits to feeding sites and potential nesting sites by several colonies of Tapinoma erraticum was studied in the laboratory. During the feeding phase ant use of space was significantly asymmetrical (different visit frequencies to identical sites) and reflects environmental structuring. Such asymmetrical patterns of space use may have influenced subsequent orientation of nest search and nest site selection after experimental disturbance. When the colony was disturbed, i.e when the water source and the opaque nest cover were removed activity remained mainly diurnal. There was relative increase in frequency of visits to the subsequently chosen nesting site as compared with visits to feeding sites. Selected nests could be in a zone visited frequently before disturbance, for example close to a feeding source, but other parameters must be considered to account for colony choice. The question of a collective decision making is discussed.