Microhabitat segregation of co-existing gastropod species

The formation of aggregations of four co-existing species of nerite gastropod was investigated on a tropical rocky shore in north Queensland, Australia. The results demonstrated that all species formed mono-specific aggregations, each of which had a strong fidelity for aggregating within a particular microhabitat type. Hence there was a distinct segregation of microhabitat usage among the four co-existing, ecologically similar species, and this segregation did not differ spatially or temporally. These results indicate that spatial and temporal fluctuations of abiotic conditions had little impact on the formation of aggregations, and that factors such as competition for microhabitats among species may play a greater role in the formation and maintenance of intertidal gastropod aggregations than previously thought.