5 research outputs found
Fish prey of antarctic fur seals, Arctocephalus gazella, during the summer-autumn period at Laurie Island, South Orkney Islands
The fish component in the diet of Antarctic fur seals, Arctocelaphus gazella, was investigated at Laurie Island, South Orkney Islands from mid January to April 1988. Fish otoliths occured in 78.8% of faecal droppings. Most of the otoliths extracted from scats belonged to Myctophid fish (93.4%), mainly Electrona antarcitca and Gymnoscopelus nicholsi. These two fish species thus constituted the bulk of the diet. A greater percentage of the otoliths from G. nicholsi (31.1%) in this study were considered suitable for measurement in comparison with 10.3% from scats at Heard island in 1990 and 11.4% atMacquarie Island in 1988/98. This lesser degree of erosion would suggest that foraging areas of fur seals during this study were closer to land than during previous studies. During the period studied, the commercial fishery around the South Orkneys was not based on Myctophid fish so there was no direct competition for fish between the fur seals and fisheries
The diet of Antarctic fur seals, Arctocephalus gazella, during the summer-autumn period at Mossman Peninsula Laurie Island (South Orkneys)
From mid January to April 1988 a total of 105 faecal samples of non breeding male fur seals, Arctocephalus gazella, was collected at Mossman Peninsula, Laurie Island. Examination of scats containing prey remains showed that fur seals fed mainly on krill, occuring in 100% of samples but fish were also a common food item (78.8%). Myctophids constituted more than 90% of fish taken by fur seals. Squid beaks occured in 34.3% of scats, being more common in the autumn period
Gastrointestinal helminths of Adélie penguins (Pygoscelis adeliae) from Antarctica
Knowledge about parasitic organisms in Antarctica is scarce and fragmentary. The study reported here adds to the knowledge of gastrointestinal parasites of the Adélie penguin (Pygoscelis adeliae) (Sphenisciformes), from 25 de Mayo/King George Island (South Shetlands), Bahia Esperanza (Hope Bay) and Avian Island (Antarctica). Thirty-five freshly dead specimens (20 chicks and 15 adults) were collected from December 2007 to December 2014 and examined for internal macroparasites. Three adult parasite species were found: one Cestoda, Parorchites zederi, and two Nematoda, Stegophorus macronectes and Tetrameres sp. Immature Tetrabothrius sp. were found in hosts from Avian Island. Helminth communities are known to be related to host feeding behaviours. Low parasite richness observed in Adélie penguins could be related to the stenophagic and pelagic diet of this host species, which feeds almost exclusively on krill.Keywords: Parorchites zederi; Stegophorus macronectes; Tetrameres sp.; parasites; ecosystem health.(Published: 16 June 2016)Citation: Polar Research 2016, 35, 28516,http://dx.doi.org/10.3402/polar.v35.2851