The role of iceberg scours in niche separation within the Antarctic fish genus Trematomus

Species of the Antarctic fish genus Trematomus occupy different trophic nic hes. It is not clear, however, whether small-scale variability in benthic c ommunity structure affects niche separation. Therefore abundance and biomas s of fish were determined and stomach content and food composition were com pared in areas affected by iceberg scours and unaffected areas in the Wedde ll Sea. Trematomus eulepidotus. T. lepidorhinus and T. scotti dominate undi sturbed areas. whereas T. nicolai and especially T. pennellii dominate dist urbed areas. Total stomach content and number of prey taxa per fish are hig her in preferred than in non-preferred areas. These findings indicate that small-scale horizontal patterns caused by iceberg scours play a distinct ro le in Trematomus niche separation.