Non-crustacean plankton was studied during summer cruises to the northern Norwegian Sea from 1996 to 1998. The dominant species in the investigated area were Aglantha digitale (Hydrozoa) and Sagitta elegans (Chaetognatha). The average density, mean biomass and interannual changes of zooplankton are presented against the background of sea temperatures. The results of this work indicate the very strong inter-annual variability of non-crustacean zooplankton abundance. Correlations with minor changes in sea temperature were noted only for hydromedusae.
Sixty seven zooplankton taxa were recorded in a total of 5 WP-2 net vertical hauls carried out in a year round cycle in Admiralty Bay. Copepoda were the most common and abundant group and Oithona similis was the dominant species throughout the area. Polychaeta, Ostracoda and Chaetognatha were also rather common and abundant. Euphausiacea, Amphi-poda and Salpae occured mainly in the central part and the outlet area of the bay. No differences in zooplankton assemblages diversity in the four investigated areas of Admiralty Bay were encountered. However, distinct differences in species richness between the zooplankton of Ezcurra Inlet and the main basin of the bay were observed. The composition of zooplankton was rather stable throughout the year, but seasonal occurrences of larvae of Polychaeta, Crustacea, Echino-dermata and Ascidiacea were noted. A Ust of the 174 zooplankton taxa ever found in Admiralty Bay is presented by combining the present results with the existing scientific data.
This paper presents preliminary data on the population structure of two Antarctic crustaceans Eudorella splendida and Nototanais antarcticus, commonly occurring in Admiralty Bay (South Shetland Islands). From analysis of the material studied it can be concluded that N. antarcticus is a progynous hermaphrodite with a life cycle lasting at least two years. The life cycle of E. splendida lasts probably 3-4 years. It is a semelparous species, but some females after brooding moult and revert into the intermediate stage.
Objects that have come within the inventory are the effect of whaling activity carried out in the region of South Shetland Islands in the first half of the twentieth century. They include mainly bones of hunted animals, rarely wooden or metal objects, part of which may be related to the whaling industry. In this paper the areas of particular accumulation of these objects have been determined, and the attempts to explain the reasons for such accumulations have been made. In addition, certain suggestions for further investigations into whaling activity in the South Shetland Islands region have been put forward. During the work 158 large fragments of whale skulls, among others, have been inventoried. The total number of individuals whose preserved relics have been explored within the surveyed sections of the Admiralty Bay shores has been estimated to be 210-230.
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