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Number of results: 17
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Abstract

Horns, teeth, claws, beaks… Given this mighty arsenal it’s a wonder there isn’t more physical conflict in the animal world, such as among birds.
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Abstract

In the breeding season 1988/89, within the region of SSSI No. 8, nesting of 12 species of birds was observed. The highest number of nests — 24430 — belonged to three species of pygoscelid penguins; 77.1% were the Adelie penguin. Relatively high fluctuations in the number of penguins in some rookeries in particular breeding seasons were confirmed. During regular countings of mammals' in 1988 the presence of 5 species of Pinnipedia was noted, of which the southern elephant seal was most numerous in the summer season, whereas crabeater seal — in winter. In the region of SSSI No. 8, breeding of southern elephant seal and Weddell seal was observed. Fluctuations in the number of seals in this region in the period 1977—1988 were insignificant.
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Abstract

In 1989/90, in the region of SSSI 8 situated on King George Island 21 bird species were observed, 12 species were breeding. Dominants were 3 Pygoscelis species (19229 pairs). Five species of pinnipedians were noticed. Mirounga leonina was most abundant in January (623 individuals), Arctocephalus gazella — in February and March (890 individuals), Hydrurga leptonyx in October (39 individuals). The abundance of Leptonychotes weddelli was low and rather stable. As a result of mild winter during the study period such birds as Sterna vittata and Pygoscelis adeliae stayed near their breeding places. The scarcity of Lobodon carcinophagus was probably also a result of this mild winter.
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Abstract

Observations were carried out in Penguin Island on 27 January 1979. The results of the birds census were as follows: Pygoscelis adeliae— 1710 pairs, P. antarclica— 7058 pairs, Macronecles giganteus—512 pairs, Oceanites oceanicus — 47 pairs, Chionis alba — 5, Stercorarius skua lonnbergi — 6 pairs, Larus dominicanus — 63 pairs, Sterna vittata—18. Other species showed different requirements as regards breeding grounds. Simultaneously the following Pinnipedia were observed on Penguin Island: Mirounga leonina — 202 specimens, Arctocephalus gazella — 48 adult and 6 young individuals, Leptonychotes weddelli — 2, Lobodon carcinophagus — 1.
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Keywords Antarctic birds blood

Abstract

The red blood picture was studied in 7 species of the Antarctic birds from the regions around Arctowski Station. King George Island (South Shetland Islands). The values of hematological indices were analysed, dependent on the mode of life and body weight of the examined species.
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Abstract

Changes in the red blood picture were studied during the development of Pygoscelis adeliae, P. antarctica and P. papua. It has been found that the respiratory function of a unit of the blood volume increases with the age of the investigated birds. The mechanism of this changes is described.
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Abstract

The observations carried out on Haswell Island on 20—24 January 1979 showed the occurrence of 7 species of nesting birds: Pygoscelis adeliae — about 36000 individuals including about 11300 young. Stercorarius skua maccormicki— 76 adults and 15 young, Daption capensis — 220+/- 10 nests, Fulmarlus glacialoides — 3150 +/- 200 nests, Thalassoica antarctica — 250 +/- 10 nests, Oceanites oceanicus — about 500 nests and Pagodroma nivea — about 10 nests. The time of hatching and moulting was found to be 15—20 days earlier, and the percentage of two-egg clutches in nests of Procellariidae was lower as compared with the literature data. More of the two-egg clutches were found for Stercorarius skua maccormicki. The krill dominated in the food of studied species of Procellariidae. Biometrical data for eggs of the majority of studied bird species were gathered.
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Abstract

A serological study to detect antibodies against microbes in avian mycoplasmosis (Mycoplasma gallisepticum and M. synoviae), and salmonellosis (Salmonella gallinarum and S. pullorum) was carried out. A hundred and twelve Antarctic birds (42 Adelie penguins, Pygoscelis adeliae, 30 southern giant petrels, Macronectes giganteus and 40 skuas, Catharacta antarctica and C. maccormicki) from King George Island, the South Shetland Islands, and Laurie Island, the South Orkney Islands in Antarctica were studied. The serological test used in this study was a rapid agglutination test. According to the results and considering the number of samples analysed, it is reasonable to believe that Adelie penguins, southern giant petrels, and skuas populations of the areas mentioned above are free from mycoplasmosis and salmonellosis.
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Abstract

Flying bird counts were carried out at Esperanza Bay (62°24'S, 56°59'W), Antarctic Peninsula, between November 1989 and February 1990. Six breeding species (Oceanites oceanicus, Chionis alba, Catharacta lonnbergi, Catharacta maccormicki, Larus dominicanus and Sterna vittata) and six visitor species (Macronectes giganteus, Fulmarus glacialoides, Daption capense, Pagodroma nivea, Fregetta tropica and Phalacrocorax atriceps) were recorded. Kelp gull and Antarctic tern populations have decreased in relation to the data by previous authors, perhaps as a result of the increased activity at Esperanza Station. Cygnus melanocoryphus was recorded for the first time at Esperanza Bay.
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Abstract

In the region of the Admiralty Bay 12 nesting bird species were encountered of a total abundance of 40890 pairs and biomass amounting to about 395000 kg Three penguin species constituted 91.7% in abundance, their biomass constituting 98.7% of the whole community. Densities of abundance and biomass of adult birds in relation to the living area of penguins (i.e. 775 km2) ranged from 32.3 to 121.4 indiv. km-2 and from 115.1 to 4730 kg k m-2.
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Abstract

A survey of breeding birds was carried out during the summer 1997-98 in several localities of the northern Danco Coast, Antarctic Peninsula. A total of 10 species were recorded: Pygoscelis antarctica (3234 pairs), P. papua (1888), Macronectes giganteus (76), Daption capense (61), Oceanites oceanicus (104), Phalacrocorax bransfieldensis (92), Ononis alba (15), Catharacta maccormicki (168), Lams dominicanus (583) and Sterna vittata (160 pairs).
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Abstract

Energy delivered to the nests of Wilson's storm petrel, Oceanites oceanicus (Kuhl, 1820), was evaluated by measurement of the oxygen consumption of brooding adult birds and nestlings of different ages. During the brooding period adult birds have to deliver more than 180 kJ per visit to the nest vs. less than 170 kJ during the rest of the nesting period. It seems likely that the parental ability to deliver large quantities of food per visit affects the duration of the brooding period and therefore also affects growth rates of Wilson's storm petrel chicks and the duration of their nesting period.
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Abstract

How environmental conditions influence current distributions of organisms at the local scale in sensitive High Arctic freshwaters is essential to understand in order to better comprehend the cascading consequences of the ongoing climate change. This knowledge is also important background data for paleolimnological assessments of long-Term limnoecological changes and in describing the range of environmental variability. We sampled five limnologically different freshwater sites from the Fuglebergsletta marine terrace in Hornsund, southern Svalbard, for aquatic invertebrates. Invertebrate communities were tested against non-climatic environmental drivers as limnological and catchment variables. A clear separation in the communities between the sites was observed. The largest and deepest lake was characterized by a diverse Chironomidae community but Cladocera were absent. In a pond with marine influence, crustaceans, such as Ostracoda, Amphipoda, and calanoid Copepoda were the most abundant invertebrates. Two nutrient-rich ponds were dominated by a chironomid, Orthocladius consobrinus, whereas themost eutrophic pond was dominated by the cladoceran Daphnia pulex, suggesting decreasing diversity along with the trophic status. Overall, nutrient related variables appeared to have an important influence on the invertebrate community composition and diversity, the trophic state of the sites being linked with their exposure to geese guano. Other segregating variables included water color, presence/absence of fish, abundance of aquatic vegetation and lake depth. These results suggest that since most of these variables are climate-driven at a larger scale, the impacts of the ongoing climate change will have cumulative effects on aquatic ecosystems.
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Abstract

Studies of the chemical composition of surface freshwaters of the Fugleberget drainage basin, Spitsbergen, were performed in the summer of 1979. It was found that activity of birds (little auk) is the main factor differentiating the chemical properties of waters of the drainage basin. The birds faeces cause the enrichment of waters with nutrients, fertilizing the environment. There is a dependence of the concentration of determined water chemistry parameters on the distance from the bird colony.
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Abstract

Fossil bird remains assignable to ratites (palaeognathous birds) are described from the Paleogene strata of the La Meseta Formation of Seymour Island, Antarctic Peninsula. This record sheds new light on Gondwana's avian history.
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Abstract

In the last two decades several new concepts of photodetectors to improve their performance have been proposed. New strategies are especially addressed to the group of so called high-operating-temperature detectors where - apart from increasing of operating temperature - both the size and power consumption reduction is expected. In this paper a new strategy in the photo-detector design is presented - the barrier detectors: CnBn; CnBnN+, CpBn and unipolar barrier photodiodes. In spite of considering barrier detectors based on AIIIBV bulk compounds and type-II superlattices as having theoretically a better performance than those based on HgCdTe, the latter compound is also used to fabricate barrier detectors. Among many new applications of barrier detectors the detection of explosives can be extremely important due to an increased threat of terrorist attacks. This paper presents the status of the barrier detectors and compares the performance of mid-wave HgCdTe barrier detectors and unipolar barrier photodiodes.
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Abstract

Contents of PCBs was investigated using the gas chromatography method in the tissue of four Antarctic migratory birds: Oceanites oceanicus, Larus dominicanus, Catharacta skua and Sterna vittata, and the three penguin species: Pvgoscelis adeliae, P. papua and P. antarctica. Samples were collected at King George Island in February 1978 and, for comparison, in March 1983. The highest PCBs content was recorded in the adipose tissue of O. oceanicus and C. skua (15.7 and 1.2 ppm). Differences in the content of these compounds in the tissue of various penguin species in 1978 was observed. The mean cumulation level of PCBs in the adipose tissue of penguins was higher in 1983 than in 1978. Differences in the level of PCBs contents in the tissue of migratory birds were related to their winter migrations to areas polluted to various degress with PCBs remains. A tendency to the increase of the contamination of penguin tissues with PCBs was observed. This tendency was related to the increase of vhe pollution of the Antarctic environment with these compounds.
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