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Maria V Gavrilo - One of the best experts on this subject based on the ideXlab platform.
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Sharing wintering grounds does not synchronize annual survival in a high Arctic seabird, the little Auk
Marine Ecology Progress Series, 2020Co-Authors: Sébastien Descamps, David Gremillet, Jerome Fort, Maria V Gavrilo, Dariusz Jakubas, Hallvard Strøm, Harald Steen, Benjamin Merkel, Rémi Choquet, K JerstadAbstract:Sharing the same wintering grounds by avian populations breeding in various areas may synchronize fluctuations in vital rates, which could increase the risk of extinction. Here, by combining multi-colony tracking with long-term capture-recapture data, we studied the winter distribution and annual survival of the most numerous Arctic seabird, the little Auk Alle alle. We assessed whether little Auks from different breeding populations in Svalbard and Franz Josef Land use the same wintering grounds and if this leads to synchronized survival. Our results indicate that birds from the Svalbard colonies shared similar wintering grounds, although differences existed in the proportion of birds from each colony using the different areas. Little Auks from Franz Josef Land generally spent the winter in a separate area, but some individuals wintered in the Iceland Sea with Svalbard populations. Survival data from 3 Svalbard colonies collected in 2005-2018 indicated that sharing wintering grounds did not synchronize little Auk annual survival rates. However, it is clear that the Iceland Sea is an important wintering area for little Auks, and environmental changes in this area could have widespread impacts on many populations.
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Sharing wintering grounds does not synchronize annual survival in a high Arctic seabird, the little Auk
Marine Ecology Progress Series, 2020Co-Authors: S Descamps, Jerome Fort, Maria V Gavrilo, Benjamin Merkel, Rémi Choquet, H Strøm, H Steen, D Grémillet, D Jakubas, K JerstadAbstract:Sharing the same wintering grounds by avian populations breeding in various areas may synchronize fluctuations in vital rates, which could increase the risk of extinction. Here, by combining multi-colony tracking with long-term capture-recapture data, we studied the winter distribution and annual survival of the most numerous Arctic seabird, the little Auk Alle alle. We assessed whether or not little Auks from different breeding populations in Svalbard and Franz Josef Land use the same wintering grounds and if this leads to synchronized survival. Our results indicate that birds from the Svalbard colonies shared similar wintering grounds, though differences existed in the proportion of birds from each colony using the different areas. Little Auks from Franz Josef Land generally spent the winter in a separate area but some individuals wintered in the Iceland Sea with Svalbard populations. Survival data from three Svalbard colonies collected in 2005-2018 indicated that sharing wintering grounds did not synchronize little Auk annual survival rates. However, it is clear that the Iceland Sea is an important wintering area for little Auks and environmental changes in this area could have widespread impacts on many populations.
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arctic warming nonlinear impacts of sea ice and glacier melt on seabird foraging
Global Change Biology, 2015Co-Authors: David Gremillet, Jerome Fort, Francoise Amelineau, Elena Zakharova, Tangi Le Bot, Enric Sala, Maria V GavriloAbstract:Arctic climate change has profound impacts on the cryosphere, notably via shrinking sea-ice cover and retreating glaciers, and it is essential to evaluate and forecast the ecological consequences of such changes. We studied zooplankton-feeding little Auks (Alle alle), a key sentinel species of the Arctic, at their northernmost breeding site in Franz-Josef Land (80°N), Russian Arctic. We tested the hypothesis that little Auks still benefit from pristine arctic environmental conditions in this remote area. To this end we analysed remote-sensing data on sea-ice and coastal glacier dynamics collected in our study area across 1979-2013. Further, we recorded little Auk foraging behaviour using miniature electronic tags attached to the birds in the summer of 2013, and compared it with similar data collected at three localities across the Atlantic Arctic. We also compared current and historical data on Franz-Josef Land little Auk diet, morphometrics and chick-growth curves. Our analyses reveal that summer sea-ice retreated markedly during the last decade, leaving the Franz-Josef Land archipelago virtually sea-ice free each summer since 2005. This had a profound impact on little Auk foraging, which lost their sea-ice associated prey. Concomitantly, large coastal glaciers retreated rapidly, releasing large volumes of melt water. Zooplankton is stunned by cold and osmotic shock at the boundary between glacier melt and coastal waters, creating new foraging hotspots for little Auks. Birds therefore switched from foraging at distant ice-edge localities, to highly profitable feeding at glacier melt-water fronts within <5 km of their breeding site. Through this behavioural plasticity little Auks maintained their chick growth rates, but showed a 4% decrease in adult body mass. Our study demonstrates that arctic cryosphere changes may have antagonistic ecological consequences on coastal trophic flow. Such non-linear responses complicate modelling exercises of current and future polar ecosystem dynamics.
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Arctic warming: non-linear impacts of sea-ice and glacier melt on seabird foraging
Global Change Biology, 2015Co-Authors: David Gremillet, Jerome Fort, Francoise Amelineau, Elena Zakharova, Enric Sala, Tangi Le Bot, Maria V GavriloAbstract:Arctic climate change has profound impacts on the cryosphere, notably via shrinking sea-ice cover and retreating glaciers, and it is essential to evaluate and forecast the ecological consequences of such changes. We studied zooplankton-feeding little Auks (Alle alle), a key sentinel species of the Arctic, at their northernmost breeding site in Franz-Josef Land (80°N), Russian Arctic. We tested the hypothesis that little Auks still benefit from pristine arctic environmental conditions in this remote area. To this end we analysed remote-sensing data on sea-ice and coastal glacier dynamics collected in our study area across 1979-2013. Further, we recorded little Auk foraging behaviour using miniature electronic tags attached to the birds in the summer of 2013, and compared it with similar data collected at three localities across the Atlantic Arctic. We also compared current and historical data on Franz-Josef Land little Auk diet, morphometrics and chick-growth curves. Our analyses reveal that summer sea-ice retreated markedly during the last decade, leaving the Franz-Josef Land archipelago virtually sea-ice free each summer since 2005. This had a profound impact on little Auk foraging, which lost their sea-ice associated prey. Concomitantly, large coastal glaciers retreated rapidly, releasing large volumes of melt water. Zooplankton is stunned by cold and osmotic shock at the boundary between glacier melt and coastal waters, creating new foraging hotspots for little Auks. Birds therefore switched from foraging at distant ice-edge localities, to highly profitable feeding at glacier melt-water fronts within
Dariusz Jakubas - One of the best experts on this subject based on the ideXlab platform.
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Sharing wintering grounds does not synchronize annual survival in a high Arctic seabird, the little Auk
Marine Ecology Progress Series, 2020Co-Authors: Sébastien Descamps, David Gremillet, Jerome Fort, Maria V Gavrilo, Dariusz Jakubas, Hallvard Strøm, Harald Steen, Benjamin Merkel, Rémi Choquet, K JerstadAbstract:Sharing the same wintering grounds by avian populations breeding in various areas may synchronize fluctuations in vital rates, which could increase the risk of extinction. Here, by combining multi-colony tracking with long-term capture-recapture data, we studied the winter distribution and annual survival of the most numerous Arctic seabird, the little Auk Alle alle. We assessed whether little Auks from different breeding populations in Svalbard and Franz Josef Land use the same wintering grounds and if this leads to synchronized survival. Our results indicate that birds from the Svalbard colonies shared similar wintering grounds, although differences existed in the proportion of birds from each colony using the different areas. Little Auks from Franz Josef Land generally spent the winter in a separate area, but some individuals wintered in the Iceland Sea with Svalbard populations. Survival data from 3 Svalbard colonies collected in 2005-2018 indicated that sharing wintering grounds did not synchronize little Auk annual survival rates. However, it is clear that the Iceland Sea is an important wintering area for little Auks, and environmental changes in this area could have widespread impacts on many populations.
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Duration of female parental care and their survival in the little Auk Alle alle - are these two traits linked?
Behavioral Ecology and Sociobiology, 2020Co-Authors: Katarzyna Wojczulanis-jakubas, Dariusz Jakubas, Nina J. Karnovsky, Dorota Kidawa, Marina Jiménez-muñoz, Diana J. Cole, Eleni MatechouAbstract:Desertion of offspring before its independence by one of the parents is observed in a number of avian species with bi-parental care but reasons for this strategy are not fully understood. This behaviour is particularly intriguing in species where bi-parental care is crucial to raise the brood successfully. Here, we focus on the little Auk, Alle alle, a small seabird with intensive bi-parental care, where the female deserts the brood at the end of the chick rearing period. The little Auk example is interesting as most hypotheses to explain desertion of the brood by females (e.g. “re-mating hypothesis”, “body condition hypothesis”) have been rejected for this species. Here, we analysed a possible relationship between the duration of female parental care over the chick and her chances to survive to the next breeding season. We performed the study in two breeding colonies on Spitsbergen with different foraging conditions – more favourable in Hornsund and less favourable in Magdalenefjorden. We predicted that in Hornsund females would stay for shorter periods of time with the brood and would have higher survival rates in comparison with birds from Magdalenefjorden. We found that indeed in less favourable conditions of Magdalenefjorden, females stay longer with the brood than in the more favourable conditions of Hornsund. Moreover, female survival was negatively affected by the length of stay in the brood. Nevertheless, duration of female parental care over the chick was not related to their parental efforts, earlier in the chick rearing period, and survival of males and females was similar. Thus, although females brood desertion and winter survival are linked, the relationship is not straightforward. When bi-parental care is crucial to raise the brood successfully, one parent desertion raises the question of why this happens. We examined this issue in the little Auk, a small seabird with females deserting the brood at the end of the chick rearing period. We hypothesised that females deserting the brood save residual energy and, in this way, increases their chance to survive to the next breeding season. We found that duration of female parental care depends on environmental conditions, with longer staying with the brood in less favourable conditions. As expected, female survival decreased with duration of their staying with the brood but it was not related to their parental efforts (i.e. number of chick feedings, duration of foraging flights). In addition, survival of males and females was similar. Thus, although little Auk females brood desertion and winter survival are linked, the relationship is not straightforward.
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Flexibility of little Auks foraging in various oceanographic features in a changing Arctic
Scientific reports, 2020Co-Authors: Dariusz Jakubas, Katarzyna Wojczulanis-jakubas, Rafał Boehnke, Katarzyna Blachowiak-samolyk, Lech Iliszko, Dorota Kidawa, Lech StempniewiczAbstract:Using GPS-tracked individuals, we compared foraging ecology and reproductive output of a High-Arctic zooplanktivorous seabird, the little Auk Alle alle, between three years differing in environmental conditions (sea surface temperature). Despite contrasting environmental conditions, average foraging fights distance and duration were generally similar in all studied years. Also, in all years foraging locations visited by the little Auk parents during short trips (ST, for chick provisioning) were significantly closer to the colony compared to those visited during long trips (LTs, mainly for adults' self-maintenance). Nevertheless, we also found some differences in the little Auk foraging behaviour: duration of LTs was the longest in the coldest year suggesting more time for resting for adults compared to warmer years. Besides, birds foraged closer to the colony and in significantly colder water in the coldest year. Interestingly, these differences did not affect chick diet: in all the years, the energy content of food loads was similar, with the Arctic copepod, Calanus glacialis copepodite stage V being the most preferred prey item (>73% of items by number and >67% by energy content). Also chick survival was similar in all the study years. However, when examining chicks growth rate we found that their peak body mass was lower in warmer years suggesting that overall conditions in the two warm years were less favourable. While our results, demonstrate a great foraging flexibility by little Auks, they also point out their vulnerability to changing environmental conditions.
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Determinants of the little Auk (Alle alle) breeding colony location and size in W and NW coast of Spitsbergen.
PloS one, 2019Co-Authors: Liliana Katarzyna Keslinka, Katarzyna Wojczulanis-jakubas, Dariusz Jakubas, Grzegorz NeubauerAbstract:Many seabirds breed in large aggregations, making it difficult to estimate their population size and habitat preferences. This knowledge is particularly important considering their function in food webs and ecosystem services. In this study, we investigated the factors affecting distribution and abundance of the little Auk Alle alle, a seabird considered a keystone species of the Arctic ecosystem. We performed the study on the W and the NW coast of Spitsbergen. Using Generalized Additive Models (GAMs) and Conditional Inference Tree (CIT) we examined factors related to presence/absence and size (estimated number of breeding pairs) of the little Auk colonies. We also tested the nesting preferences for geographical features such as aspect, slope angle, altitude, solar radiation, rock type, and distance to foraging grounds. Our findings indicate that the occurrence of little Auk breeding colonies is non-random and highly attributed to environmental factors. The probability of colony occurrence was significantly associated with altitude (negative relationship; preference to sites situated lower), solar radiation (positive relationship; the higher radiation, the more likely colony occurrence) and slope (positive relationship; the steeper a slope, the more likely colony occurrence), whilst aspect appeared non-significant (though the probability of colony occurrence peaked at southern slopes). Colony size was significantly associated with rock type (larger colonies in amphibolite and quartzite). The distance to foraging grounds did not appear to affect the probability of colony occurrence and size, implying that birds may choose optimal breeding sites at the cost of longer foraging flights. We estimated the Spitsbergen little Auk breeding population at 728 529 (5-95% CI: 479 312-986 352). Spitsbergen comprises ca 1.9% (95% CI: 1.2%-2.7%) of the world breeding population and represents the third most important breeding area for the species, following the W and the E coast of Greenland.
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Assortative mating patterns of multiple phenotypic traits in a long-lived seabird
Ibis, 2018Co-Authors: Katarzyna Wojczulanis-jakubas, Dariusz Jakubas, Szymon M. Drobniak, Monika Kulpińska-chamera, Olivier ChastelAbstract:Choosing the right mate is crucial for successful breeding, particularly in monogamous species with long and extensive bi-parental care, and when the breeding pair is presumed to last many seasons. We investigated the degree of assortative mating in the Little Auk Alle alle, a long-lived seabird with long-term pair bonds and bi-parental care for fixed (morphological) and labile (physiological) traits. Using randomization tests, we suggest assortative mating with respect to wing length, extent of the white area on the upper eyelid and hormonal stress response (the difference between stress-induced and baseline corticosterone levels). We discuss how the assortative mating patterns that we found in the Little Auk may be adaptive.
David Gremillet - One of the best experts on this subject based on the ideXlab platform.
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Sharing wintering grounds does not synchronize annual survival in a high Arctic seabird, the little Auk
Marine Ecology Progress Series, 2020Co-Authors: Sébastien Descamps, David Gremillet, Jerome Fort, Maria V Gavrilo, Dariusz Jakubas, Hallvard Strøm, Harald Steen, Benjamin Merkel, Rémi Choquet, K JerstadAbstract:Sharing the same wintering grounds by avian populations breeding in various areas may synchronize fluctuations in vital rates, which could increase the risk of extinction. Here, by combining multi-colony tracking with long-term capture-recapture data, we studied the winter distribution and annual survival of the most numerous Arctic seabird, the little Auk Alle alle. We assessed whether little Auks from different breeding populations in Svalbard and Franz Josef Land use the same wintering grounds and if this leads to synchronized survival. Our results indicate that birds from the Svalbard colonies shared similar wintering grounds, although differences existed in the proportion of birds from each colony using the different areas. Little Auks from Franz Josef Land generally spent the winter in a separate area, but some individuals wintered in the Iceland Sea with Svalbard populations. Survival data from 3 Svalbard colonies collected in 2005-2018 indicated that sharing wintering grounds did not synchronize little Auk annual survival rates. However, it is clear that the Iceland Sea is an important wintering area for little Auks, and environmental changes in this area could have widespread impacts on many populations.
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arctic warming nonlinear impacts of sea ice and glacier melt on seabird foraging
Global Change Biology, 2015Co-Authors: David Gremillet, Jerome Fort, Francoise Amelineau, Elena Zakharova, Tangi Le Bot, Enric Sala, Maria V GavriloAbstract:Arctic climate change has profound impacts on the cryosphere, notably via shrinking sea-ice cover and retreating glaciers, and it is essential to evaluate and forecast the ecological consequences of such changes. We studied zooplankton-feeding little Auks (Alle alle), a key sentinel species of the Arctic, at their northernmost breeding site in Franz-Josef Land (80°N), Russian Arctic. We tested the hypothesis that little Auks still benefit from pristine arctic environmental conditions in this remote area. To this end we analysed remote-sensing data on sea-ice and coastal glacier dynamics collected in our study area across 1979-2013. Further, we recorded little Auk foraging behaviour using miniature electronic tags attached to the birds in the summer of 2013, and compared it with similar data collected at three localities across the Atlantic Arctic. We also compared current and historical data on Franz-Josef Land little Auk diet, morphometrics and chick-growth curves. Our analyses reveal that summer sea-ice retreated markedly during the last decade, leaving the Franz-Josef Land archipelago virtually sea-ice free each summer since 2005. This had a profound impact on little Auk foraging, which lost their sea-ice associated prey. Concomitantly, large coastal glaciers retreated rapidly, releasing large volumes of melt water. Zooplankton is stunned by cold and osmotic shock at the boundary between glacier melt and coastal waters, creating new foraging hotspots for little Auks. Birds therefore switched from foraging at distant ice-edge localities, to highly profitable feeding at glacier melt-water fronts within <5 km of their breeding site. Through this behavioural plasticity little Auks maintained their chick growth rates, but showed a 4% decrease in adult body mass. Our study demonstrates that arctic cryosphere changes may have antagonistic ecological consequences on coastal trophic flow. Such non-linear responses complicate modelling exercises of current and future polar ecosystem dynamics.
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Arctic warming: non-linear impacts of sea-ice and glacier melt on seabird foraging
Global Change Biology, 2015Co-Authors: David Gremillet, Jerome Fort, Francoise Amelineau, Elena Zakharova, Enric Sala, Tangi Le Bot, Maria V GavriloAbstract:Arctic climate change has profound impacts on the cryosphere, notably via shrinking sea-ice cover and retreating glaciers, and it is essential to evaluate and forecast the ecological consequences of such changes. We studied zooplankton-feeding little Auks (Alle alle), a key sentinel species of the Arctic, at their northernmost breeding site in Franz-Josef Land (80°N), Russian Arctic. We tested the hypothesis that little Auks still benefit from pristine arctic environmental conditions in this remote area. To this end we analysed remote-sensing data on sea-ice and coastal glacier dynamics collected in our study area across 1979-2013. Further, we recorded little Auk foraging behaviour using miniature electronic tags attached to the birds in the summer of 2013, and compared it with similar data collected at three localities across the Atlantic Arctic. We also compared current and historical data on Franz-Josef Land little Auk diet, morphometrics and chick-growth curves. Our analyses reveal that summer sea-ice retreated markedly during the last decade, leaving the Franz-Josef Land archipelago virtually sea-ice free each summer since 2005. This had a profound impact on little Auk foraging, which lost their sea-ice associated prey. Concomitantly, large coastal glaciers retreated rapidly, releasing large volumes of melt water. Zooplankton is stunned by cold and osmotic shock at the boundary between glacier melt and coastal waters, creating new foraging hotspots for little Auks. Birds therefore switched from foraging at distant ice-edge localities, to highly profitable feeding at glacier melt-water fronts within
Jerome Fort - One of the best experts on this subject based on the ideXlab platform.
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Sharing wintering grounds does not synchronize annual survival in a high Arctic seabird, the little Auk
Marine Ecology Progress Series, 2020Co-Authors: Sébastien Descamps, David Gremillet, Jerome Fort, Maria V Gavrilo, Dariusz Jakubas, Hallvard Strøm, Harald Steen, Benjamin Merkel, Rémi Choquet, K JerstadAbstract:Sharing the same wintering grounds by avian populations breeding in various areas may synchronize fluctuations in vital rates, which could increase the risk of extinction. Here, by combining multi-colony tracking with long-term capture-recapture data, we studied the winter distribution and annual survival of the most numerous Arctic seabird, the little Auk Alle alle. We assessed whether little Auks from different breeding populations in Svalbard and Franz Josef Land use the same wintering grounds and if this leads to synchronized survival. Our results indicate that birds from the Svalbard colonies shared similar wintering grounds, although differences existed in the proportion of birds from each colony using the different areas. Little Auks from Franz Josef Land generally spent the winter in a separate area, but some individuals wintered in the Iceland Sea with Svalbard populations. Survival data from 3 Svalbard colonies collected in 2005-2018 indicated that sharing wintering grounds did not synchronize little Auk annual survival rates. However, it is clear that the Iceland Sea is an important wintering area for little Auks, and environmental changes in this area could have widespread impacts on many populations.
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Sharing wintering grounds does not synchronize annual survival in a high Arctic seabird, the little Auk
Marine Ecology Progress Series, 2020Co-Authors: S Descamps, Jerome Fort, Maria V Gavrilo, Benjamin Merkel, Rémi Choquet, H Strøm, H Steen, D Grémillet, D Jakubas, K JerstadAbstract:Sharing the same wintering grounds by avian populations breeding in various areas may synchronize fluctuations in vital rates, which could increase the risk of extinction. Here, by combining multi-colony tracking with long-term capture-recapture data, we studied the winter distribution and annual survival of the most numerous Arctic seabird, the little Auk Alle alle. We assessed whether or not little Auks from different breeding populations in Svalbard and Franz Josef Land use the same wintering grounds and if this leads to synchronized survival. Our results indicate that birds from the Svalbard colonies shared similar wintering grounds, though differences existed in the proportion of birds from each colony using the different areas. Little Auks from Franz Josef Land generally spent the winter in a separate area but some individuals wintered in the Iceland Sea with Svalbard populations. Survival data from three Svalbard colonies collected in 2005-2018 indicated that sharing wintering grounds did not synchronize little Auk annual survival rates. However, it is clear that the Iceland Sea is an important wintering area for little Auks and environmental changes in this area could have widespread impacts on many populations.
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arctic warming nonlinear impacts of sea ice and glacier melt on seabird foraging
Global Change Biology, 2015Co-Authors: David Gremillet, Jerome Fort, Francoise Amelineau, Elena Zakharova, Tangi Le Bot, Enric Sala, Maria V GavriloAbstract:Arctic climate change has profound impacts on the cryosphere, notably via shrinking sea-ice cover and retreating glaciers, and it is essential to evaluate and forecast the ecological consequences of such changes. We studied zooplankton-feeding little Auks (Alle alle), a key sentinel species of the Arctic, at their northernmost breeding site in Franz-Josef Land (80°N), Russian Arctic. We tested the hypothesis that little Auks still benefit from pristine arctic environmental conditions in this remote area. To this end we analysed remote-sensing data on sea-ice and coastal glacier dynamics collected in our study area across 1979-2013. Further, we recorded little Auk foraging behaviour using miniature electronic tags attached to the birds in the summer of 2013, and compared it with similar data collected at three localities across the Atlantic Arctic. We also compared current and historical data on Franz-Josef Land little Auk diet, morphometrics and chick-growth curves. Our analyses reveal that summer sea-ice retreated markedly during the last decade, leaving the Franz-Josef Land archipelago virtually sea-ice free each summer since 2005. This had a profound impact on little Auk foraging, which lost their sea-ice associated prey. Concomitantly, large coastal glaciers retreated rapidly, releasing large volumes of melt water. Zooplankton is stunned by cold and osmotic shock at the boundary between glacier melt and coastal waters, creating new foraging hotspots for little Auks. Birds therefore switched from foraging at distant ice-edge localities, to highly profitable feeding at glacier melt-water fronts within <5 km of their breeding site. Through this behavioural plasticity little Auks maintained their chick growth rates, but showed a 4% decrease in adult body mass. Our study demonstrates that arctic cryosphere changes may have antagonistic ecological consequences on coastal trophic flow. Such non-linear responses complicate modelling exercises of current and future polar ecosystem dynamics.
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Arctic warming: non-linear impacts of sea-ice and glacier melt on seabird foraging
Global Change Biology, 2015Co-Authors: David Gremillet, Jerome Fort, Francoise Amelineau, Elena Zakharova, Enric Sala, Tangi Le Bot, Maria V GavriloAbstract:Arctic climate change has profound impacts on the cryosphere, notably via shrinking sea-ice cover and retreating glaciers, and it is essential to evaluate and forecast the ecological consequences of such changes. We studied zooplankton-feeding little Auks (Alle alle), a key sentinel species of the Arctic, at their northernmost breeding site in Franz-Josef Land (80°N), Russian Arctic. We tested the hypothesis that little Auks still benefit from pristine arctic environmental conditions in this remote area. To this end we analysed remote-sensing data on sea-ice and coastal glacier dynamics collected in our study area across 1979-2013. Further, we recorded little Auk foraging behaviour using miniature electronic tags attached to the birds in the summer of 2013, and compared it with similar data collected at three localities across the Atlantic Arctic. We also compared current and historical data on Franz-Josef Land little Auk diet, morphometrics and chick-growth curves. Our analyses reveal that summer sea-ice retreated markedly during the last decade, leaving the Franz-Josef Land archipelago virtually sea-ice free each summer since 2005. This had a profound impact on little Auk foraging, which lost their sea-ice associated prey. Concomitantly, large coastal glaciers retreated rapidly, releasing large volumes of melt water. Zooplankton is stunned by cold and osmotic shock at the boundary between glacier melt and coastal waters, creating new foraging hotspots for little Auks. Birds therefore switched from foraging at distant ice-edge localities, to highly profitable feeding at glacier melt-water fronts within
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Composition of chick meals from one of the main little Auk (Alle alle) breeding colonies in Northwest Greenland
Polar Biology, 2014Co-Authors: Marie Frandsen, Jerome Fort, Frank Rigét, Anders Galatius, Anders MosbechAbstract:During the last decade, increasing information on little Auk (Alle alle) biology, ecology and behaviour has been reported. However, only a few of these studies have focused on the breeding population in the Avanersuaq (Thule) district of Northwest Greenland, where 80 % of the global little Auk population is estimated to breed. This study reports on the chick diet composition from one of the largest colonies, the Paakitsoq colony, located on the south-eastern margin of the North Water (NOW) Polynya. Results revealed the highest proportion of Calanus hyperboreus, a large lipid-rich copepod, in chick diet reported for any little Auk colony. Results confirmed that the cold, highly productive waters of the NOW Polynya are favourable foraging grounds for the little Auks during the breeding season. Species diversity within and between the chick meals was low, which probably eflects a high availability of a few preferred prey species. Individual chick meals were generally low in number of prey items and total energy content compared with other published results. This may be explained by a higher feeding frequency or by the samples being collected late in the breeding period (during late chick rearing), when chicks have a reduced growth rate and may require less energy than at earlier developmental stages.
Katarzyna Wojczulanis-jakubas - One of the best experts on this subject based on the ideXlab platform.
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Duration of female parental care and their survival in the little Auk Alle alle - are these two traits linked?
Behavioral Ecology and Sociobiology, 2020Co-Authors: Katarzyna Wojczulanis-jakubas, Dariusz Jakubas, Nina J. Karnovsky, Dorota Kidawa, Marina Jiménez-muñoz, Diana J. Cole, Eleni MatechouAbstract:Desertion of offspring before its independence by one of the parents is observed in a number of avian species with bi-parental care but reasons for this strategy are not fully understood. This behaviour is particularly intriguing in species where bi-parental care is crucial to raise the brood successfully. Here, we focus on the little Auk, Alle alle, a small seabird with intensive bi-parental care, where the female deserts the brood at the end of the chick rearing period. The little Auk example is interesting as most hypotheses to explain desertion of the brood by females (e.g. “re-mating hypothesis”, “body condition hypothesis”) have been rejected for this species. Here, we analysed a possible relationship between the duration of female parental care over the chick and her chances to survive to the next breeding season. We performed the study in two breeding colonies on Spitsbergen with different foraging conditions – more favourable in Hornsund and less favourable in Magdalenefjorden. We predicted that in Hornsund females would stay for shorter periods of time with the brood and would have higher survival rates in comparison with birds from Magdalenefjorden. We found that indeed in less favourable conditions of Magdalenefjorden, females stay longer with the brood than in the more favourable conditions of Hornsund. Moreover, female survival was negatively affected by the length of stay in the brood. Nevertheless, duration of female parental care over the chick was not related to their parental efforts, earlier in the chick rearing period, and survival of males and females was similar. Thus, although females brood desertion and winter survival are linked, the relationship is not straightforward. When bi-parental care is crucial to raise the brood successfully, one parent desertion raises the question of why this happens. We examined this issue in the little Auk, a small seabird with females deserting the brood at the end of the chick rearing period. We hypothesised that females deserting the brood save residual energy and, in this way, increases their chance to survive to the next breeding season. We found that duration of female parental care depends on environmental conditions, with longer staying with the brood in less favourable conditions. As expected, female survival decreased with duration of their staying with the brood but it was not related to their parental efforts (i.e. number of chick feedings, duration of foraging flights). In addition, survival of males and females was similar. Thus, although little Auk females brood desertion and winter survival are linked, the relationship is not straightforward.
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Flexibility of little Auks foraging in various oceanographic features in a changing Arctic
Scientific reports, 2020Co-Authors: Dariusz Jakubas, Katarzyna Wojczulanis-jakubas, Rafał Boehnke, Katarzyna Blachowiak-samolyk, Lech Iliszko, Dorota Kidawa, Lech StempniewiczAbstract:Using GPS-tracked individuals, we compared foraging ecology and reproductive output of a High-Arctic zooplanktivorous seabird, the little Auk Alle alle, between three years differing in environmental conditions (sea surface temperature). Despite contrasting environmental conditions, average foraging fights distance and duration were generally similar in all studied years. Also, in all years foraging locations visited by the little Auk parents during short trips (ST, for chick provisioning) were significantly closer to the colony compared to those visited during long trips (LTs, mainly for adults' self-maintenance). Nevertheless, we also found some differences in the little Auk foraging behaviour: duration of LTs was the longest in the coldest year suggesting more time for resting for adults compared to warmer years. Besides, birds foraged closer to the colony and in significantly colder water in the coldest year. Interestingly, these differences did not affect chick diet: in all the years, the energy content of food loads was similar, with the Arctic copepod, Calanus glacialis copepodite stage V being the most preferred prey item (>73% of items by number and >67% by energy content). Also chick survival was similar in all the study years. However, when examining chicks growth rate we found that their peak body mass was lower in warmer years suggesting that overall conditions in the two warm years were less favourable. While our results, demonstrate a great foraging flexibility by little Auks, they also point out their vulnerability to changing environmental conditions.
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Determinants of the little Auk (Alle alle) breeding colony location and size in W and NW coast of Spitsbergen.
PloS one, 2019Co-Authors: Liliana Katarzyna Keslinka, Katarzyna Wojczulanis-jakubas, Dariusz Jakubas, Grzegorz NeubauerAbstract:Many seabirds breed in large aggregations, making it difficult to estimate their population size and habitat preferences. This knowledge is particularly important considering their function in food webs and ecosystem services. In this study, we investigated the factors affecting distribution and abundance of the little Auk Alle alle, a seabird considered a keystone species of the Arctic ecosystem. We performed the study on the W and the NW coast of Spitsbergen. Using Generalized Additive Models (GAMs) and Conditional Inference Tree (CIT) we examined factors related to presence/absence and size (estimated number of breeding pairs) of the little Auk colonies. We also tested the nesting preferences for geographical features such as aspect, slope angle, altitude, solar radiation, rock type, and distance to foraging grounds. Our findings indicate that the occurrence of little Auk breeding colonies is non-random and highly attributed to environmental factors. The probability of colony occurrence was significantly associated with altitude (negative relationship; preference to sites situated lower), solar radiation (positive relationship; the higher radiation, the more likely colony occurrence) and slope (positive relationship; the steeper a slope, the more likely colony occurrence), whilst aspect appeared non-significant (though the probability of colony occurrence peaked at southern slopes). Colony size was significantly associated with rock type (larger colonies in amphibolite and quartzite). The distance to foraging grounds did not appear to affect the probability of colony occurrence and size, implying that birds may choose optimal breeding sites at the cost of longer foraging flights. We estimated the Spitsbergen little Auk breeding population at 728 529 (5-95% CI: 479 312-986 352). Spitsbergen comprises ca 1.9% (95% CI: 1.2%-2.7%) of the world breeding population and represents the third most important breeding area for the species, following the W and the E coast of Greenland.
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Assortative mating patterns of multiple phenotypic traits in a long-lived seabird
Ibis, 2018Co-Authors: Katarzyna Wojczulanis-jakubas, Dariusz Jakubas, Szymon M. Drobniak, Monika Kulpińska-chamera, Olivier ChastelAbstract:Choosing the right mate is crucial for successful breeding, particularly in monogamous species with long and extensive bi-parental care, and when the breeding pair is presumed to last many seasons. We investigated the degree of assortative mating in the Little Auk Alle alle, a long-lived seabird with long-term pair bonds and bi-parental care for fixed (morphological) and labile (physiological) traits. Using randomization tests, we suggest assortative mating with respect to wing length, extent of the white area on the upper eyelid and hormonal stress response (the difference between stress-induced and baseline corticosterone levels). We discuss how the assortative mating patterns that we found in the Little Auk may be adaptive.
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Parental efforts of an Arctic seabird, the little Auk Alle alle, under variable foraging conditions
Marine Biology Research, 2014Co-Authors: Dorota Kidawa, Katarzyna Wojczulanis-jakubas, Dariusz Jakubas, Rafał Boehnke, Lech Stempniewicz, Emilia Trudnowska, Liliana Keslinka-nawrot, Katarzyna Blachowiak-samolykAbstract:AbstractObserved large-scale changes in climate and oceanography, which are especially pronounced in the Arctic, represent profound challenges for upper trophic predators. Knowledge about the extent to which marine predators are able to adjust to environmental variability is essential in order to assess the impact of changing oceanic conditions on the Arctic ecosystem. The main goal of this study was to investigate the impact of oceanographic conditions that varied on an inter-annual and inter-colony basis on the foraging and breeding strategy of a zooplanktivorous alcid, the little Auk Alle alle. The study was conducted in two little Auk breeding colonies in Spitsbergen (Hornsund and Magdalenefjord) located in different hydrographical regimes in two contrasting seasons (2009 and 2010). This article provides a comprehensive study linking a number of variables describing foraging ground quality, measured directly at sea, with the birds' foraging strategy, parental efforts, body condition and survival of ne...
