The diet of the Antarctic fish Trematomus newnesi Boulenger, 1902 (Nototheniidae) from Terra Nova Bay, Ross Sea

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A coastal ichthyological survey was carried out in Terra Nova Bay, Ross Sea during the Italian Antarctic Expedition 1987/1988. Vacchi et al. (1992) described the composition of the coastal fish community. Stomach content analysis was conducted on Trematomus bernacchii and T. pennellii to evaluate the trophic overlap (Vacchi et al. 1994). During the survey, several specimens of T. newnesi were caught at 92 m depth. This fish is a coastal species widespread in the high-Antarctic Zone and also known from the South Shetland Islands and the South Orkney Islands (DeWitt et al. 1990). Although T. newnesi was found down to 400 m depth (Tiedtke & Kock 1989), it seems more abundant in very shallow inshore waters (Naito & Iwami 1982, Williams 1988). Andriashev (1970) and Williams(1988) stated T. newnesi was a cryopelagic species associated with the underside of the sea-ice. At Signy Island, T. newnesi was described as semipelagic species eating amphipods (Richardson 1975). Eastman & DeVries (1982) consider it to be both a cryopelagic and benthic species in McMurdo Sound. Targett (1981) found that T. newnesi feeds on krill and plankton at the South Orkney Islands. Planktivory has also been indicated at the South Shetland Islands (Casaux et al. 1990).