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The paper presents the results of taxonomical investigation of the genus Cladonia Hill ex P. Browne from King George Island. Individuals belonging to this lichen genus were studied using methods of classical herbarium taxonomy supported by chemical analysis. Fourteen species have been recognized in the study area, with C. asahinae J.W. Thomson being reported from King George Island for the first time, and C. cervicornis subsp. mawsonii reported as new for the South Shetland Islands. The occurrence of C. cariosa is confirmed for the Antarctic region. The diagnostic characters, ecology and important remarks referring to particular species are briefly presented. An updated key for identification of the species from King George Island and neighbouring islands of South Shetlands is included.
During the austral summer of 2002/2003 the author collected 38 marine and/or glacio-marine sediment samples from Admiralty Bay on King George Island (South Shetland Islands, West Antarctica). Recent "living" (Rose Bengal stained) and "dead" (subfossil) benthic foraminifera represented by 105 species belonging to 65 genera are recognized in samples from water depths of up to 520 m. They show large spatial variability. Four distinctive foraminiferal zones within the fjord of Admiralty Bay were recognized and analyzed in terms of environmental conditions. The zones are: restricted coves, open inlets, intermediate-, and deep-waters. The major environmental factors, which dictate foraminiferal distribution, are closely related to bathymetry and distance to open sea. Sediment composition and chlorophyll content appear to have minor influence on foraminiferal communities. Most diverse, deep-water faunas dominate water-depths below 200 m, which seems to be the lowest limit of atmospheric and meltwater influence. In waters shallower than 200 m, environmental features, affecting distribution of various benthic foraminiferal assemblages, appear to be sedimentation rate and hydrographic isolation. The results of this study gives promise to use the Admiralty Bay foraminiferal distribution pattern as a paleo- environmental tool for shallow- to intermediate-water Quaternary marine research in fjord settings of the South Shetland Islands.
The level of polymorphism, genetic variability and relatedness of the Antarctic hairgrass Deschampsia antarctica Desv. Populations from South Shetlands Is. (King George I., Penguin I., Livingstone I.), from vicinity of Antarctic Peninsula (Galindez I., Uruguay I.), and Falklands Is. (Jason Is., Sealion I.) were studied using the AFLP approach. Six EcoRI/MseI type selective primer pairs combinations were used for AFLP profiling and amplified scoreable DNA fragments; than AMOVA and PCA were performed. The level of molecular variability among all individuals from all the analysed populations was low and reach only 5.4 % irrespective of the distance between the localities and it was not significant at a broader geographical scale, even among the three groups of populations (South Shetlands Is., vicinity of Antarctic Peninsula, and Falklands Is.). PCA analysis shows that all populations formed uniform groups according to their locations.
New data on the infection with Acanthocephala of 33 fish caught in Admiralty Bay in November 2007 to January 2008 are given. These fish belong to 5 species: Notothenia rossii (22 immature specimens), Lindbergichthys nudifrons (n = 7), Trematomus bernacchii (n = 1), T. newnesi (n = 1) and Harpagifer antarcticus (n = 2). Three species of Echinorhynchida: Aspersentis megarhynchus, Metacanthocephalus dalmori and M. johnstoni and four species of Polymorphida: Corynosoma arctocephali, C. bullosum, C. hamanni and C. pseudohamanni, were found. Prevalence of N. rossii and L. nudifrons was 100%. The mean abundance of infection of N. rossii (125.09) was larger than that of Notothenia coriiceps (82.93). Data of infection of N. rossii in 2007 was almost identical with that in 1979 (mean abundance 118.66). The most abundant in this host were A. megarhynchus, M. johnstoni, C. hamanni and C. pseudohamanni (mean abundances 36.36, 29.77, 13.86 and 44.73, respectively). In total Echinorhynchida were more abundant than Polymorphida in 2007/08 (66.18 versus 58.91). Reverse situation was in 1979 (mean abundance 47.36 for Echinorhynchida and 71.3 for Polymorphida. Only 7 L. nudifrons were examined in 2007/08 and Echinorhynchida were more numerous in this host (mean abundance 26.71) than Polymorphida (10.29). Single specimens of other fish were infected with a few Acanthocephala belonging to species recorded in the same hosts with those found in 1978/79.
This study describes the seasonal and annual changes in the diet of non-breeding male Antarctic fur seals (Arctocephalus gazella) through the analysis of faeces collected on shore during four summer seasons (1993/94-1996/97) in the area of Admiralty Bay (King George Island, South Shetlands). Krill was the most frequent prey, found in 88.3% of the 473 samples. Fish was present in 84.7% of the samples, cephalopods and penguins in 12.5% each. Of the 3832 isolated otoliths, 3737 were identified as belonging to 17 fish species. The most numerous species were: Gymnoscopelus nicholsi, Electrona antarctica, Chionodraco rastro- spinosus, Pleuragramma antarcticum, and Notolepis coatsi. In January, almost exclusively, were taken pelagic Myctophidae constituting up to 90% of the total consumed fish biomass. However, in February and March, the number of bentho-pelagic Channichthyidae and Noto- theniidae as well as pelagic Paralepididae increased significantly, up to 45% of the biomass. In April the biomass of Myctophidae increased again. The frequency of squid and penguin occurrence was similar and low, but considering the greater individual body mass of penguins, their role as a food item may be much greater. In March and April, penguins could be as important prey item as fish. The amount of krill in the diet of Antarctic fur seals declined with a concomitant decrease in the mature krill availability. This appears to have been compensated by an increased frequency of the fur seal to eat fish and penguins.
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