Dietary composition oj juvenile Dissostichus eleginoides (Pisces, Nototheniidae) around Shag Rocks and South Georgia, Antarctica

BARRERA-ORO ESTEBAN; CASAUX RICARDO; MARSCHOFF ENRIQUE

POLAR BIOLOGY

SPRINGER

Año: 2005 vol. 28 p. 637 - 641

0722-4060

Diet composition of juvenile Dissostichus eleginoides (Pisces, Nototheniidae) around Shag Rocks and South Georgia, Antarctica. Esteban R. Barrera-Oro, Ricardo J. Casaux and Enrique R. Marschoff* *Instituto Antártico Argentino, Cerrito 1248, A1010AAZ Buenos Aires, Argentina E-mail: ¡Error! No se encuentra el origen de la referencia.  Key words: Antarctica, toothfish, diet, ecology. Abstract A diet analysis of the patagonian toothfish Dissostichus eleginoides, caught in the South Georgia Islands area in March-April 1996, was carried out by frequency of occurrence (F%) and coefficient ?Q? (%) methods. The samples consisted chiefly of immature specimens, with predominant length ranges of 30-70 cm (TL). Fish was by far the main food in the shelves of Shag Rocks (SR) and South Georgia (SG) (63% as sole prey). Krill appeared as secondary food, although its importance was overestimated by the frequency of occurrence method. Cephalopods and mysids occurred scarcely in the stomachs and only at SR and SG respectively. Lepidonotothen kempi, Champsocephalus gunnari and Chaenocephalus aceratus constituted the main fish prey and their variability between SR and SG depended on their local abundance. The large proportion of fish exhibiting stomachs full or close to fullness (together 62%), suggests that feeding intensity of the species was high.