Preferencje help
Polish version English version Język
Widoczny [Schowaj] Abstrakt
Liczba wyników

Znaleziono wyników: 14

Liczba wyników na stronie
Pierwsza strona wyników Pięć stron wyników wstecz Poprzednia strona wyników Strona / 1 Następna strona wyników Pięć stron wyników wprzód Ostatnia strona wyników

Wyniki wyszukiwania

Wyszukiwano:
w słowach kluczowych:  sea bird
help Sortuj według:

help Ogranicz wyniki do:
Pierwsza strona wyników Pięć stron wyników wstecz Poprzednia strona wyników Strona / 1 Następna strona wyników Pięć stron wyników wprzód Ostatnia strona wyników
1

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
|
2014
|
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.
2
Artykuł dostępny w postaci pełnego tekstu - kliknij by otworzyć plik
Content available

Can seabirds modify carbon burial in fjords?

100%
Weslawski J. M., Urbanski J., Gluchowska M., Grzelak K., Kotwicki L., Kwasniewski S., Legezynska J., Wiktor J., Wlodarska-Kowalczuk M., Zaborska A., Zajaczkowski M., Stempniewicz L.
Oceanologia
|
2017
|
tom 59
|
nr 4
Two high latitude fjords of Spitsbergen (Hornsund 77°N and Kongsfjorden 79°N) are regarded as being highly productive (70 g and 50 gC m−2 year−1) and having organic-rich sediments. Hornsund has more organic matter in its sediments (8%), nearly half of it of terrestrial origin, while most of that in Kongsfjorden (5%) comes from fresh, marine sources (microplankton). Analysis of the carbon sources in both fjords shows that a major difference is the much larger seabird population in Hornsund-dominated with over 100 thousands pairs of plankton feeding little auks in Hornsund versus 2 thousand pairs in Kongsfjorden, and marine food consumption estimated as 5573 tonnes of carbon in Hornsund, versus 3047 tonnes in Kongsfjorden during one month of chick feeding period. Seabird colonies supply rich ornithogenic tundra (595 tonnes of C, as against only 266 tonnes of C in the Kongsfjorden tundra). No much of the terrestrial carbon, flushed out or wind-blown to the fjord, is consumed on the seabed – a state of affairs that is reflected by the low metabolic activity of bacteria and benthos and the lower benthic biomass in Hornsund than in Kongsfjorden.
3

Factors affecting brood patch development in Magellanic Penguins Spheniscus magellanicus

84%
Barrionuevo M., Marchisio N., Frere E.
Acta Ornithologica
|
2016
|
tom 51
|
nr 1
Brood patches allow the transfer of heat to eggs for their successful embryonic development, and in many species determine egg temperature during incubation. We investigated brood patch development of Magellanic Penguins Spheniscus magellanicus in Isla Quiroga, Argentina, during 2012-2013. Here, we evaluate if brood patch development (in a narrow sense i.e. increase of the brood patch area and temperature measured with an electronic probe thermometer) varies according to laying date of the eggs, and with respect to adults' body condition and size, total clutch volume, and/or the sex of the adults. We found that brood patch temperature reaches its maximum when egg laying is finished, while brood patch area is fully developed starting from the end of the first quarter of the incubation period. The later the penguins started to breed the warmer the initial brood patches — when first egg is laid. Besides, the incubation period was shorter in penguins breeding late. Furthermore, adults in a good body condition had cooler initial brood patches than adults with poor body condition. In contrast, total clutch volume, body size index, and sex of the adults were not related to brood patch development. We conclude that initial brood patch temperature in Magellanic Penguins is associated with environmental factors, like laying date, and physiological attributes, like body condition.
4

Isolation of Campylobacter lari from seabirds in Hope Bay, Antarctica

84%
Leotta G., Vigo G., Giacoboni G.
Polish Polar Research
|
2006
|
tom 27
|
nr 4
303-308
Campylobacter is one of the most common bacterial causes of diarrheal illness in humans. This study describes the isolation of Campylobacter lari from seabirds during 4 consecutive summers (2000-2003) in Hope Bay, Antarctic Peninsula. One hundred and twenty-two spontaneously dead Antarctic seabirds were studied. Ten Campylobacter lari isolates from 7 skuas (Stercorarius spp.), 2 kelp gulls (Larus dominicanus), and 1 Adelie penguin (Pygoscelis adeliae) were identified by phenotypical characteristics. Human activity in Antarctica was identified as a possible source of infectious agents, and migratory birds could be carriers of infectious diseases. However, nothing is known about zoonotic entero- pathogens causing diseases in humans living in the Antarctic region. We demonstrated that seabirds carried C. lari in their intestines, and that they were settled around the lakes where humans are supplied with fresh water. Consumption of fresh water from Antarctic lakes contaminated with feces of seabirds could be a risk of human campylobacteriosis. This is the first report of C. lari isolated from seabirds in Hope Bay, Antarctica.
5

Penguin past: The current state of knowledge

84%
Jadwiszczak P.
Polish Polar Research
|
2009
|
tom 30
|
nr 1
3-28
6

The aortic valve and other heart structures of selected species of sea birds in a morphological and imaging scope

84%
Bartyzel B. J.
Electronic Journal of Polish Agricultural Universities. Series Veterinary Medicine
|
2009
|
tom 12
|
nr 4
7

Is cleaning penguins worth the effort? Results from flipper banding

84%
Whittington P.
The Ring
|
1997
|
tom 19
|
nr 1-2
8

Biodiversity and energy transfer to top trophic levels in two contrasting Arctic fjords

67%
Weslawski J. M., Kwasniewski S., Stempniewicz L., Blachowiak-Samolyk K.
Polish Polar Research
|
2006
|
tom 27
|
nr 3
259-278
The food and foraging strategy of fifteen species of seabirds and sea mammals from two high Arctic fjords were analysed. One of the fjords, Kongsfjord, is strongly influenced by warm waters from the Atlantic, while Hornsund is of a more Arctic character. Prey species in the Atlantic waters were more diverse (82 species and 16 functional groups) compared to those of Arctic waters (67 prey species and 14 functional groups). The consumption of top predators from Hornsund in the peak season of July was estimated at 2.86*106 MJ, while that in Kongsfjord was 1.35*106 MJ. For the analysed function of the ecosystem (the transfer of energy to the top trophic levels) the specific character of prey species is of key importance and not the diversity, abundance or biomass per se. Lower species diversity and biomass in Arctic waters is compensated for by the occurrence of larger individuals of these species, which permits top predators to prey directly on lower trophic levels.
9
Artykuł dostępny w postaci pełnego tekstu - kliknij by otworzyć plik
Content available

New Miocene sulid birds from Peru and considerations on their Neogene fossil record in the Eastern Pacific Ocean

67%
Stucchi M., Varas-Malca R. M., Urbina-Schmitt M.
Acta Palaeontologica Polonica
|
2016
|
tom 61
|
nr 2
Boobies and gannets (family Sulidae) are the most specialized plunge divers among seabirds. Their fossil record along the Pacific coast of South America extends to the early Middle Miocene. Here we describe three new species of sulids: Sula brandi sp. nov., Sula figueroae sp. nov., and Ramphastosula aguirrei sp. nov., from the early Late Miocene of the Pisco Formation (Peru). Two of them are relatives of the living genus Sula, which represents medium and large-sized boobies. A new species of the extinct genus Ramphastosula is also described, adding to the discussion of possible alternative feeding strategies among sulids. The fossil record suggests that sympatric sulids exhibit different body sizes at least since the Oligocene epoch, a strategy related with resource partitioning. Furthermore, we find current analysis and knowledge of the fossil record unsuitable to evaluate properly seabird diversity changes through time.
10

Sea-birds from coastal and non-coastal, archaeological and natural Pleistocene deposits or not all unexpected deposition is of human origin

67%
Stewart J. R.
Acta Zoologica Cracoviensia
|
2002
|
tom 45
|
nr Spec.issue
11

The earliest fossil record of a medium-sized penguin

59%
Jadwiszczak P., Chapman S. D.
Polish Polar Research
|
2011
|
tom 32
|
nr 3
12
Artykuł dostępny w postaci pełnego tekstu - kliknij by otworzyć plik
Content available

Climate change influences on Antarctic bird populations

59%
Korczak-Abshire M.
Papers on Global Change
|
2010
|
nr 17
Rapid changes in the major environmental variables like: temperature, wind and precipitation have occurred in the Antarctic region during the last 50 years. In this very sensitive region, even small changes can potentially lead to major environmental perturbations. Then the climate change poses a new challenge to the survival of Antarctic wildlife. As important bioindicators of changes in the ecosystem seabirds and their response to the climate perturbations have been recorded. Atmospheric warming and consequent changes in sea ice conditions have been hypothesized to differentially affect predator populations due to different predator life-history strategies and substantially altered krill recruitment dynamics.
13

Studies on beached birds and oil pollution in Latvia

59%
Kurochkin A.
The Ring
|
1993
|
tom 15
|
nr 1-2
14

Dioksyny i furany [PCDD-Fs] w ptakach morskich z poludniowej czesci Morza Baltyckiego

43%
Falandysz J., Bergqvist P. A., Rappe C.
Bromatologia i Chemia Toksykologiczna
|
1998
|
tom 31
|
nr 1
75-78
Oznaczono stężenie polichlorowanych dibenzo-p-dioksyn (PCDDs) i polichlorowanych dibenzofuranów (PCDFs) w tkankach trzech grup ptaków morskich - wszystkożernych (mewa pospolita Larus canus), rybożernych (nur rdzawoszyi Gavia stellata, alka krzywonosa Alca torda, nurzyk podbielały Uria aalge) i drapieżnych (bielik Haliaeetus albicilla), z części południowej Morza Bałtyckiego. 2,3,4,7,8-penta-CDF i 1,2,3,7,8- penta-CDD wykryto w największym stężeniu, a w mniejszym wiele innych mniej toksycznych PCDDs i PCDFs.
Pierwsza strona wyników Pięć stron wyników wstecz Poprzednia strona wyników Strona / 1 Następna strona wyników Pięć stron wyników wprzód Ostatnia strona wyników
JavaScript jest wyłączony w Twojej przeglądarce internetowej. Włącz go, a następnie odśwież stronę, aby móc w pełni z niej korzystać.