CCAMLR

The diet of breeding Antarctic shags Phalacrocorax bransfieldensis was investigated at four colonies at the Danco Coast, Antarctic Peninsula, by the analysis of 616 pellets (regurgitated casts) collected from December 1997 to February 1998. Overall, demersal-benthic fish were the most frequent and important prey at all the colonies sampled, followed by octopods and gastropods. Among fish, Notothenia coriiceps was the main prey in all of the sampling sites, followed in similar importance by G. gibberifrons in Cape Herschel, Primavera Island and Midas Island and in less importance by H. antarcticus in Py Point. Between colonies there were marked differences in the size of the fish consumed. The largest specimens were eaten by shags from Midas Islands whereas the smallest ones by those from Py Point. This was mainly influenced by the number of specimens of the smallest fish species, H. antarcticus, consumed at this last colony. The differences in the composition of the diet may be related to the different foraging areas used by the shags. Our results differ from those presented in the only two previous studies on the diet of this shag at the Antarctic Peninsula. The shags at the Danco Coast preyed markedly more intensively on G. gibberifrons than those at the South Shetland Islands. This finding indicates a low abundance of this fish species in inshore waters (

The diet of the South Georgia Shag Phalacrocorax georgianus at Laurie Island, South Orkney Islands, was studied by the analysis of 337 pellets (regurgitated casts) collected during the 1995, 1996, 1997 and 1998 breeding seasons. Demersal-benthic fish were by far the main prey, followed by molluscs (mainly octopods and bivalves) and polychaetes. Harpagifer antarcticus (in 1995 and 1998) and Lepidonotothen nudifrons (1996 and 1997) were the most frequent preys followed by Gobionotothen gibberifrons or Trematomus newnesi. Harpagifer antarcticus, followed by L. nudifrons or T. newnesi, was the most numerous prey in all of the seasons and predominated in mass in 1995 and 1996, followed by Notothenia coriiceps and L. nudifrons. In 1997 G. gibberifrons and N. coriiceps were the species that most contributed to the diet whereas N. coriiceps and H. antarcticus did in 1998. Our results differ from those reported also for the South Orkney Islands in previous studies. These differences could be due to the use of different diet analysis methods and to shags-related and/or fisheries-related changes in the food availability. If assumed that the fisheries carried out in the area affected the structure and abundance of the fish populations, the comparison of our results with historical data may be indicating a recovery of G. gibberifrons in inshore waters around the archipelago.

The international CCAMLR Survey 2000 was conducted to support an updated estimate of the large scale krill biomass in the South Atlantic Sector of the Antarctic. Four vessels from Japan, Russia, the UK and the USA participated in the study during which 22 parallel hydroacoustic transects as well as four small scale shelf grids were investigated. Standard net tows were carried out during midnight and midday stations. Additional samples were take by opening-closing nets for the identification of acoustic targets. Analyses on the combined data sets from the net sampling program indicate that krill distribution showed three distinct geographical clusters of size frequency distributions. Small to medium sized juvenile and subadult krill mainly occurred east of the South Orkney Islands. Adult krill predominately smaller than 50 mm mean length dominated in a band to the north of the first cluster, while the adult krill larger than 50 mm mean size was found to the north of cluster 2 , but at the same time was mostly restricted to the area west of the South Orkney Islands. Implications are discussed arising from the stock composition and distribution patterns.

In 1998 the 2nd Ukrainian Marine Complex Antarctic Expedition (UMCAE) on board scientific research vessel "Ernst Krenkel" took place in the western part of the Atlantic sector of the Antarctic. It was arranged by the Ukrainian Antarctic Center of the Ministry for Affairs of Science and Technologies of Ukraine. The preliminary analysis of the data compiled allows revealing some specific features of the environmental conditions, state of the krill population, other functionally important components in the pelagic ecosystems of the areas under review. In Subarea 48.2 there were fixed water low temperatures and great amount of icebergs (together all these factors characterize the navigational season of 1998 as abnormally cold), recruitment of the stock (for the first time for recent years), low abundance of krill larvae, plenty of salps (their abundance and biomass occurred to be higher 1.6 times than the same indices for 1997). In Subarea 48.1 there were revealed the differences in size composition of krill and in its biomass on the fishing sites near the Elephant Island and the King George Island. In the former of them the basis of catches comprises krill of the third size group (evidently, generation of 1995); in the latter - krill of the second and third group with the evident share of the recruitment group.