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1

Avifauna of Hornsund area, SW Spitsbergen: present state and recent changes

100%
Wojczulanis-Jakubas K., Jakubas D., Stempniewicz L.
Polish Polar Research
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2008
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tom 29
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nr 2
187-197
The purpose of this study was to present the current state of avifauna in the vicinity of Polish Polar Station, at Hornsund (SW Spitsbergen). During four seasons (2003-2006) ten bird species were recorded as breeding there. Among them colonial little auk and Arctic tern were most abundant. Six additional species were noted during the breeding season but none of them bred there and their visits in the study plots were a consequence of their nesting nearby study area. Remaining 11 species were recorded during migration. The most pronounced changes over the last 35 years has been a considerable increase in number of barnacle geese exploiting the tundra as their foraging and resting area.
2

Body size variation of European Storm Petrels Hydrobates pelagicus in relation to environmental variables

100%
Jakubas D., Wojczulanis-Jakubas K., Jensen J.-K.
Acta Ornithologica
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2014
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tom 49
|
nr 1
Body size differentiation may have developed in response to environmental gradients. A pattern of large individuals prevailing in colder areas is often observed and is explained by the heat conservation hypothesis (Bergmann's rule). To understand patterns driving body size variation in a pelagic seabird, the European Storm Petrel Hydrobates pelagicus, we examined the relationship between wing length, body mass and environmental variables in breeding areas (sea surface temperature, air temperature and wind speed). As this species has been divided into two subspecies: Mediterranean H. p. melitensis and Atlantic H. p. pelagicus, we performed the analyses at different scales (species, Atlantic subspecies and regional North Atlantic). At the species and subspecies scales, there was a longitudinal increase in wing length from west to east. At the subspecies and regional scale, we found a latitudinal increase in this variable from south to north. This result and the significant increase of wing length with decreasing sea surface and air temperatures are concordant with Bergmann's rule. In addition, body mass at the species and subspecies scales decreased with increasing wind speed, what may have a functional implication (small body mass may increase manoeuvrability over waves in conditions of stronger wind). Both genetic (two subspecies differing in body size) and environmental factors seem to be important forces driving intercolony variation in body size. Our study on sexual size dimorphism (SSD) revealed that in 156 molecularly sexed adults from the Faeroes, wing and tail length, and body mass exhibited female-biased SSD, while head-bill length showed male-biased SSD. The best discriminant function for sexing based on body measurements correctly classified 75% of individuals. Considering low correctness of proposed functions and geographical variation of body size, use of alternative methods (e.g. molecular tools) is recommended for sex discrimination in the European Storm Petrel.
3

Faeces deposition and numbers of vertebrate herbivores in the vicinity of planktivorous seabird colonies in Hornsund, Spitsbergen

100%
Jakubas D., Zmudczynska K., Wojczulanis-Jakubas K., Stempniewicz L.
Polish Polar Research
|
2008
|
tom 29
|
nr 1
45-58
Ornithogenic tundra developing near large seabird colonies with its dense vegetation creates sites for foraging, hiding and breeding of herbivores. Grazing, trampling and faeces deposition are considered as the most important ways that vertebrate herbivores influence the plants. Excrement deposition level informs us on the intensity of grazing i.e. foraging ground attractiveness. We have compared vertebrate herbivores' faeces deposition (biomass) in the vicinity of big colonies of piscivorous (kittiwake Rissa tridactyla and Brunnich's guillemot Uria lomvia) and planktivorous (little auk Alle alle) seabirds and the control area was in Hornsund, SW Spitsbergen. Much higher level of faeces deposition was recorded nearby seabird colonies as compared to the control area. These finding points out that vertebrate herbivores concentrate and feed more intensively on rich ornithogenic pastures. Number of herbivores and their faeces deposition level recorded nearby planktivorous seabird colony were greater as compared to those found nearby the colony of piscivores. The highest number of geese (Branta bernicla and Anser brachyrhynchus) and of their faeces biomass were found near the colony of planktivorous little auk, where distinct gradient in faeces deposition level along the colony-seashore axis was recorded. Reindeers Rangifer tarandus were observed in considerable numbers near the little auk colony, and were not recorded at all near cliff-nesting sites of kittiwakes and guillemots. Total deposition of excrements produced by geese was generally higher if compared to reindeers.
4

Alczyk - sztandarowy gatunek Arktyki

100%
Wojczulanis-Jakubas K., Jakubas D., Stempniewicz L.
Kosmos
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2013
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tom 62
|
nr 3
5
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The role of wild fowl in the circulation of potentially pathogenic fungi in the biosphere

64%
Dynowska M., Biedunkiewicz A., Ejdys E., Sucharzewska E., Kubiak D., Meissner W., Wojczulanis-Jakubas K., Dziekonska-Rynko J., Goralska K., Rokicki J.
Annals of Parasitology
|
2016
|
tom 62
|
nr Suppl.
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