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Słowa kluczowe climate change Antarctica

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It’s difficult to imagine a more curious continent: Antarctica, once very austere and inhospitable, is now becoming greener as a result of climate change.
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The paper summarizes results of twenty years of seabird observations carried out between 1977 and 1996 on the western shore of Admiralty Bay (King George Island, South Shetlands, Antarctic). Changes in population size, distribution and phenology of the breeding species as well as the appearance of non-breeding species are reported. A total of 34 species of birds were observed, including 13 breeding species. Among the non-breeding species, four were observed to visit the site regularly, six rarely, and the remaining 11 were observed only occasionally. Among breeding populations, three Pygoscelis penguin species, the main krill consumers, were most numerous. The Adélie Penguin (P. adeliae) dominated among the penguins nesting in the investigated areas, reaching 23,661 breeding pairs in 1978. Two other penguin species were less abundant with population sizes of approximately 7,200 breeding pairs for the Chinstrap Penguin (P. antarcticus) and 3,100 breeding pairs for the Gentoo Penguin (P. papua) in the same year. During the following two decades, breeding populations of pygoscelid species experienced a declining trend and their numbers were reduced by 68.0% for Chinstrap, 67.1% for Gentoo, and 33.9% for Adélie Penguins. The data reported here represent a unique reference basis and provide valuable information about indicator species, suitable for comparison with contemporary observations of bird populations in the Antarctic Peninsula region, a place of rapidly occurring climate changes and intensive harvesting of marine living resources.
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The order Passeriformes is the most successful group of birds on Earth, however, its representatives are rare visitors beyond the Polar Front zone. Here we report a photo−documented record of an Austral Negrito ( Lessonia rufa ), first known occurrence of this species in the South Shetland Islands and only the second such an observation in the Antarctic region. This record was made at Lions Rump, King George Island, part of the Antarctic Specially Protected Area No. 151 (ASPA 151). There is no direct evidence of how the individual arrived at Lions Rump, but ship assistance cannot be excluded.
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A comparison between the levels of infection with Acanthocephala of the fish Notothenia coriiceps in Admiralty Bay (South Shetland Islands, Antarctic) in 1978/79 and 2007/08 is presented. The same eight acanthocephalan species, three echinorhynchids maturing in fish, Aspersentis megarhynchus (dominant species), Metacanthocephalus johnstoni (subdominant species) and M. dalmori (common species), and five polymorphids maturing in mammals and birds, Corynosoma hamanni , C. pseudohamanni (both co−dominant species), C. arctocephali and C. bullosum (both common species), and C. shackletoni (rare species), were found. Echinorhynchids were more numerous in 2007/08 (mean abundance 46.54 versus 35.35 in 1978/79), whereas polymorphids more numerous in 1978/79 (mean abundance 74.35 versus 36.40 in 2007/08). The overall results therefore demonstrated that echinorhynchids were more numerous than polymorphids in 2007/08 and the reverse was true in 1978/79. This situation is dependent mainly upon the decreased infections with C. hamanni , C. pseudohamanni and C. bullosum , and to a lesser degree upon the increasing of infections with M. johnstoni . The decrease of the three Corynosoma spp. is possibly associated with the decreasing of populations of final hosts, seals, on the shore of Admiralty Bay in the vicinity of Arctowski Station.
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Here we report a photo−documented record of a barn swallow ( Hirundo rustica ) from the South Shetland Islands. We also review previous records of passerine vagrants in the Antarctic (south of the Antarctic Convergence Zone). This barn swallow is the first re− corded member of the Hirundinidae family on King George Island and is only the second passerine recorded in the South Shetland Islands. This sighting, along with previous records of austral negrito and austral trush represent the southernmost sightings of any passerine bird anywhere in the world.
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Long term changes (46 years) in the a bundance of pygoscelid penguins breeding populations and nests distribution in the Lions Rump (King George Island) colony were investigated in three time intervals, according to previously published two censuses and one original study conducted in 2010. At that time a detailed colony map based on the GIS system was made. Results of this study showed different trends for each investigated species. In the last three decades Adélie penguin breeding populations showed strong declining tendencies (69.61%). In contrast, the population of gentoo penguins represents the reverse trend, increasing 171.85% over the same period. Observed changes in both penguin population sizes are reflected in the different spatial and geographic distribution of their nests. The population changes observed at the Lions Rump colony are consistent with the relevant pygoscelid penguin tendencies in the western Antarctic Peninsula region. Breeding penguin population dynamics at Lions Rump area with a minimal disturbance by human activity may well illustrate a natural response of those birds to environmental changes in the Antarctic.
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Słowa kluczowe Antarktyka ocieplenie klimatu

Abstrakt

Trudno sobie wyobrazić kontynent bardziej osobliwy niż Antarktyka. Szczególnie że pod wpływem zmian klimatycznych ten kiedyś wyjątkowo niegościnny ekosystem staje się coraz bardziej zielony.
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During three austral summer seasons cargo, expeditioner clothes and equipment of the Polish Antarctic Expedition were examined for the presence of alien propagules. Detailed inspections were undertaken at the station buildings, searching for any invertebrates. During each austral summer fresh fruits and vegetables were also inspected. A total of 359 invertebrates and their remains were found in cargo transported to Arctowski Station, or caught in the station’s facilities. The majority of samples were classified as cultivation pests (26%), food pests (43%), wood−destroying pests (4%), domestic insects and arachnids (15%). Through supply of the research station a wide range of alien organisms can be accidentally transported and ultimately introduced to the Antarctic. This study has clearly demonstrated that almost all cargo items can be a potential vector for alien organisms. Species from a broad range of biological groups can be transported to the Antarctic and remain in a viable state.
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During three austral summer seasons, dust and soil from clothes, boots and equipment of members of scientific expeditions and tourists visiting the Polish Antarctic Station Henryk Arctowski were collected and analysed for the presence of fungal propagules. Of a total of 60 samples, 554 colonies of fungi belonging to 19 genera were identified. Colonies of the genus Cladosporium , Penicillium and non−sporulating fungus ( Mycelia sterilia ) dominated in the examined samples. The microbiological assessment of air for the presence of fungi was also conducted at two points in the station building and two others outside the station. A total of 175 fungal colonies belonging to six genera were isolated. Colonies of the genus Penicillium were the commonest in the air samples. The potential epidemiological consequences for indigenous species as a result of unintentional transport of fungal propagules to the Antarctic biome are discussed in the light of rapid climate change in some parts of the Ant − arctic and adaptation of fungi to extreme conditions.
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