Stomach contents of Antarctic toothfish (Dissostichus mawsoni) from the Ross Sea region in 2010 and a comparison with 2003

The stomach contents of 273 Dissostichus mawsoni captured by bottom longline in the Ross Sea region during the 2010 summer fishing season were analysed. The D. mawsoni sampled were caught in 640–2127 m depths and ranged between 78 and 181 cm TL. A total of 198 stomachs contained prey items, of which 13 contained only digested prey, leaving 185 stomachs for analysis. The majority of these stomachs were collected from the continental slope (n = 164) where Whitson’s grenadier (Macrourus whitsoni) dominated the diet occurring in 37% of stomachs and accounting for 45% by weight and 52% by IRI. De Witt’s icefish, eel-cods, and glacial squid were also important occurring in about 20% of stomachs and by IRI 23%, 13%, and 8% respectively. The large onychoteuthid squid, Kondakovia longimana dominated the diet.of D. mawsoni collected from the northern area (n = 21). The results of the current study were compared to a similar study based on samples collected in 2003. Preliminary examination of the data suggested there had been no change in the diet of large (> 100 cm TL) D. mawsoni between the two years. It is planned to carry out a more rigorous analysis of these data in the coming year.