Abstract
Fishes are key component in the trophic web of Antarctic marine ecosystems, representing food for top predators, such as other fish, birds and mammals. In particular, fishes are among the most important prey of the Weddell seal, Leptonychotes weddellii . Several studies reported data on the diet and foraging ecology of Weddell seals all around the Antarctic continent, from the Ross and Weddell Seas to the South Orkney and the South Shetland Islands. In the present study we investigated the fish component in the diet of Weddell seal from the Kyiv Peninsula region, which so far represented an unexplored area. During the four-year research, a total of 16 species of fish were identified, five of them were recorded for the first time in the study area. Except for the Antarctic silverfish, which represented the most abundant prey, all other species were benthic or demersal notothenioid species. Weddell seals relied on a wide range of prey size, including both juveniles, subadult and adult ontogenetic stages. Applying a multivariate analysis of prey items, temporal factors such as month, season and year of sampling did not influence diet composition, whereas it was slightly affected on a spatial midscale. In conclusion, the food composition of the Weddell seal populations living in this area seemed to be largely determined by the local abundance of fish prey, providing evidence of a remarkable feeding plasticity of this species.