Fishes of the eastern Ross Sea, Antarctica

摘要

Antarctic fishes were sampled with 41 midwater and 6 benthic trawls during the 1999-2000 austral summer in the eastern Ross Sea. The oceanic pelagic assemblage (0-1,000 m) contained Electrona antarctica, Gymnoscopelus opisthopterus, Bathylagus antarcticus, Cyclothone kobayashii and Notolepis coatsi. These were replaced over the shelf by notothenioids, primarily Pleuragramma antarcticum. Pelagic biomass was low and concentrated below 500 m. The demersal assemblage was characteristic of East Antarctica and included seven species each of Artedidraconidae, Bathydraconidae and Channichthyidae, ten species of Nototheniidae, and three species each of Rajidae and Zoarcidae. Common species were Trematomus eulepidotus (36.5%), T. scotti (32.0%), Prionodraco evansii (4.9%), T. loennbergii (4.7%) and Chaenodraco wilsoni (4.3%). Diversity indices were highest for tows from 450 to 517 m (H'=1.90-2.35). Benthic biomass ranged from 0.7 to 3.5 t km(-2). It was generally higher in tows from 450 to 517 m (0.9-2.0 t km(-2)) although the highest biomass occurred at an inner-shelf station (238 m) due to large catches of T. eulepidotus, T. scotti and P. evansii.