The diet of the Weddell Seal Leptonychotes weddelli at Harmony Point, South Shetland Islands.

CASAUX R,; BARONI A.; CARLINI A.

POLAR BIOLOGY

SPRINGER

Lugar: Berlin; Año: 1997 vol. 18 p. 371 - 375

0722-4060

Abstract   A total of 41 faeces and 5 vomits of the Weddell Seal Leptonychotes weddelli was collected at Harmony Point, Nelson Island, South Shetland Islands, from January 14 to February 1 1996. The diet indicated by the remains in the samples was diverse and comprised of both pelagic and bentho-demersal species. Fish were the most frequent (95.7%) and numerous prey (46.2%), whereas molluscs were the most important by mass (65.8%). Octopods, mainly Pareledone charcoti, constituted the bulk of the diet (63.1% by mass), whereas the importance of the remaining molluscs was negligible. Otoliths represented 510 fish of which 491 were identified as belonging to 5 species: Gymnoscopelus nicholsi, Electrona antarctica, Lepidonotothen nudifrons, Gobionotothen gibberifrons, Nototheniops nybelini. The myctophid G. nicholsi was the most important fish prey, whereas the contribution of bentho-demersal species was low. However, the importance of that fish was over-estimated since 96% of the specimens were obtained from the five vomits analysed. The biases associated with the faecal analysis technique are discussed.