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A total of 1,103 inshore notothenioid fish were caught by means of trammel-nets in 4 sites surrounding Cierva Point (Moss Island 1; Moss Island 2; Sterneck Island; Leopardo Island), Danco Coast, West Antarctic Peninsula, during February and March 2000. The families Nototheniidae, Channichthyidae and Bathydraconidae were represented in the samples, Notothenia coriiceps being the dominant fish of the area. Gobionotothen gibberifrons and Trematomus newnesi followed in importance. In general, the fish sampled agreed in terms of number and mass with those of the South Shetland Islands area, except for a marked higher occurrence of G. gibberifrons in the Danco Coast. This supports the hypothesis that the commercial fishery around the South Shetland Islands at the end of the 1970s was responsible for the decrease in the inshore population of G. gibberifrons in that area during the last 17 years. Information on morphometry, reproduction and diet of the fish species caught is provided. [ABSTRACT FROM AUTHOR]

The analysis of 29 stomach contents collected from a colony close to Pirie Peninsula, South Orkney Islands, from 2 January to 18 February 1995, showed that fish were by far the most important prey of the Antarctic shag Phalacrocorax bransfieldensis, followed by octopods, decapods and gammarids. The fish Notothenia coriiceps constituted the bulk of the diet; however, its importance decreased by the end of the study when Lepidonotothen nudifrons was the most important prey. The composition of the stomach contents varied throughout the breeding season according to changes in the chicks' energetic demands; as chicks grew older the adults increased the mass of the loads carried to the nests, preying on larger fish, a phenomenon also observed at the South Shetland Islands. [ABSTRACT FROM AUTHOR]

Approximately 1000 specimens belonging to eight fish species were collected at Potter Cove, King George Island, South Shetland Islands, from August 1985 to May 1986. This study deals with the dominant species Notothenia neglecta, Notothenia gibberifrons, Trematomus newnesi and Notothenia rossii marmorata. Age and size structure of the fish were analyzed using scale and otolith readings. Notothenia neglecta was the most abundant species. It spawns in the austral autumn. Juvenile N. rossii marmorata migrate offshore when sexually mature. Over eight hundred stomach contents were analyzed. The four species studied were generally benthophagous. However, in summer T. newnesi and N. rossii marmorata, carried out vertical migrations, feeding on pelagic organisms. Gammarid amphipods constituted the main food in all four species. Algae were consumed regularly throughout the year and we suggest that they are intentially eaten by the fish, rather than by accident. Two 48 hour sampling periods, carried out in summer of 1987, showed that N. neglecta was more active during the day. [ABSTRACT FROM AUTHOR]

Sagittal otoliths were used for age determination in 1121 specimens of Micromesistius australis, caught in waters of the South-West Atlantic during the cruises made by the ships Walther Herwig and Shinkai Maru in agreement with the Argentine Republic, during the years 1978 and 1978/1979, respectively. The interpretation of growth rings required the otoliths to undergo a paraffin wax embedding and cutting technique. The relations otolith length-fish length and fish length-half otolith width were linear. Thus, back calculations, when necessary, were made by a simple extrapolation. Numbers of males and females were nearly equal, resulting in a sex ratio of 1:1.09. Length frequencies and age distributions were calculated for each sex separately. A significant difference in growth between sexes was found, curves for each were derived. A linear, regression was made and the Von Bertalanffy equation estimated as: Lt=56.90 [1-e], in males, and Lt=60.08 [1-e] in females, with Lt in cm and t in years. For estimation of these equation parameters age groups 2-16 years in males and 2-22 years in females were taken into account. All theoretical Lt values and almost all observed lengths for females were greater than those of males in corresponding age groups. Previously published observations about M. australis on this subject, are not in agreement or only in partial accord with present results. These are discussed. Original photographs of otolith cross sections illustrating age determination methods are presented for the first time in age and growth studies of this species. [ABSTRACT FROM AUTHOR]