Atypichthys strigatus (Pisces: Scorpididae): An opportunistic planktivore that responds to benthic disturbances and cleans other fishes

Abstract

Abstract Atypichthys strigatus (Günther) were abundant on temperate reefs in New South Wales, Australia. Dietary analyses indicated that they feed primarily on plankton, but also consume benthic organisms. Initial observations suggested thai A. strigatus respond to disturbances of the substratum for the purpose of feeding. The substratum in barrens and kelp habitats was experimentally disturbed to examine the response by A. strigatus. Significantly more A. strigatus were found in disturbed areas than in undisturbed areas and their feeding rate was greater in disturbed areas. The response by A. strigatus to disturbance was the same in barrens and kelp habitats, although there was a more marked response in the barrens habitat. Atypichthys strigatus also responded to natural disturbance by large reef fishes (e.g. Achoerodus viridis: Labridae). Furthermore, A. strigatus of a broad range of sizes (25–90 mm standard length) were observed cleaning other reef fishes. The behavioural flexibility of A. strigatus probably leads to increased feeding opportunities, and hence increased foraging success, for the fish. Moreover, it raises questions about the accuracy of partitioning fish species according to one trophic group.