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| Author | Purchet M., Melieres M.A., Pinglot J.F. & Heintzenberg J. | ||||
| Title | Estimation of Chernobyl deposition in high latitudes or high altitudes by 137 Cs measurements in snow. | Type | Conference - International - Article without Reading Comitee | ||
| Year | 1996 | Publication | Abbreviated Journal | ||
| Volume | Issue | Pages | |||
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Abstract  |
Unesco Int.Academic Conference. Ten years after the Chernobyl Catastrophe. Minsk, Belarus | ||||
| Programme | 265 | ||||
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| Area | Expedition | Conference | |||
| Notes | Approved | yes | |||
| Call Number | Serial | 240 | |||
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| Author | Mazé-Guilmo, E., Blanchet, S., McCoy, K. D. & Loot, G. | ||||
| Title | Host dispersal as the driver of parasite genetic structure: a paradigm lost? | Type | Journal Article | ||
| Year | 2016 | Publication | ECOLOGY LETTERS | Abbreviated Journal | Ecol. Lett. |
| Volume | 19 | Issue | 3 | Pages | 336–347 |
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| Abstract |
Understanding traits influencing the distribution of genetic diversity has major ecological and evolutionary implications for host–parasite interactions. The genetic structure of parasites is expected to conform to that of their hosts, because host dispersal is generally assumed to drive parasite dispersal. Here, we used a meta-analysis to test this paradigm and determine whether traits related to host dispersal correctly predict the spatial co-distribution of host and parasite genetic variation. We compiled data from empirical work on local adaptation and host–parasite population genetic structure from a wide range of taxonomic groups. We found that genetic differentiation was significantly lower in parasites than in hosts, suggesting that dispersal may often be higher for parasites. A significant correlation in the pairwise genetic differentiation of hosts and parasites was evident, but surprisingly weak. These results were largely explained by parasite reproductive mode, the proportion of free-living stages in the parasite life cycle and the geographical extent of the study; variables related to host dispersal were poor predictors of genetic patterns. Our results do not dispel the paradigm that parasite population genetic structure depends on host dispersal. Rather, we highlight that alternative factors are also important in driving the co-distribution of host and parasite genetic variation. | ||||
| Programme | 333 | ||||
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| Language | Summary Language | Original Title | |||
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| Series Volume | Series Issue | Edition | |||
| ISSN | 1461-023X | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | Approved | yes | |||
| Call Number | Serial | 6414 | |||
| Permanent link to this record | |||||
| Author | David T. Iles, Heather Lynch, Rubao Ji, Christophe Barbraud, Karine Delord, Stephanie Jenouvrier | ||||
| Title | Sea ice predicts long-term trends in Adélie penguin population growth, but not annual fluctuations: Results from a range-wide multiscale analysis | Type | Journal | ||
| Year | 2020 | Publication | Global Change Biology | Abbreviated Journal | |
| Volume | 26 | Issue | 7 | Pages | 3788-3798 |
| Keywords | Antarctica environmental variation habitat suitability niche predictability state-space stochastic uncertainty | ||||
| Abstract |
Understanding the scales at which environmental variability affects populations is critical for projecting population dynamics and species distributions in rapidly changing environments. Here we used a multilevel Bayesian analysis of range-wide survey data for Adélie penguins to characterize multidecadal and annual effects of sea ice on population growth. We found that mean sea ice concentration at breeding colonies (i.e., “prevailing” environmental conditions) had robust nonlinear effects on multidecadal population trends and explained over 85% of the variance in mean population growth rates among sites. In contrast, despite considerable year-to-year fluctuations in abundance at most breeding colonies, annual sea ice fluctuations often explained less than 10% of the temporal variance in population growth rates. Our study provides an understanding of the spatially and temporally dynamic environmental factors that define the range limits of Adélie penguins, further establishing this iconic marine predator as a true sea ice obligate and providing a firm basis for projection under scenarios of future climate change. Yet, given the weak effects of annual sea ice relative to the large unexplained variance in year-to-year growth rates, the ability to generate useful short-term forecasts of Adélie penguin breeding abundance will be extremely limited. Our approach provides a powerful framework for linking short- and longer term population processes to environmental conditions that can be applied to any species, facilitating a richer understanding of ecological predictability and sensitivity to global change. | ||||
| Programme | 109 | ||||
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| ISSN | 1365-2486 | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | Approved | yes | |||
| Call Number | Serial | 7682 | |||
| Permanent link to this record | |||||
| Author | Labrousse Sara, Vacquié-Garcia Jade, Heerah Karine, Guinet Christophe, Sallée Jean-Baptiste, Authier Matthieu, Picard Baptiste, Roquet Fabien, Bailleul Frédéric, Hindell Mark, Charrassin Jean-Benoit, | ||||
| Title | Winter use of sea ice and ocean water mass habitat by southern elephant seals: The length and breadth of the mystery | Type | Journal Article | ||
| Year | 2015 | Publication | Progress in Oceanography | Abbreviated Journal | Prog. Oceanogr. |
| Volume | 137 | Issue | A | Pages | 52-68 |
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| Abstract |
Understanding the responses of animals to the environment is crucial for identifying critical foraging habitat. Elephant seals (Mirounga leonina) from the Kerguelen Islands (49°20′S, 70°20′E) have several different foraging strategies. Why some individuals undertake long trips to the Antarctic continent while others utilize the relatively close frontal zones is poorly understood. Here, we investigate how physical properties within the sea ice zone are linked to foraging activities of southern elephant seals (SES). To do this, we first developed a new approach using indices of foraging derived from high temporal resolution dive and accelerometry data to predict foraging behaviour in an extensive, low resolution dataset from CTD-Satellite Relay Data Loggers (CTD-SRDLs). A sample of 37 post-breeding SES females were used to construct a predictive model applied to demersal and pelagic dive strategies relating prey encounter events (PEE) to dive parameters (dive duration, bottom duration, hunting-time, maximum depth, ascent speed, descent speed, sinuosity, and horizontal speed) for each strategy. We applied these models to a second sample of 35 seals, 20 males and 15 females, during the post-moult foraging trip to the Antarctic continental shelf between 2004 and 2013, which did not have fine-scale behavioural data. The females were widely distributed with important foraging activity south of the Southern Boundary Front, while males predominately travelled to the south-eastern part of the East Antarctica region. Combining our predictions of PEE with environmental features (sea ice concentration, water masses at the bottom phase of dives, bathymetry and slope index) we found higher foraging activity for females over shallower seabed depths and at the boundary between the overlying Antarctic Surface Water (AASW) and the underlying Modified Circumpolar Deep Water (MCDW). Increased biological activity associated with the upper boundary of MCDW, may provide overwintering areas for SES prey. Male foraging activity was strongly associated with pelagic dives within the Antarctic Slope Front where upwelling of nutrient rich Circumpolar Deep Water onto surface water may enhance and concentrate resources. A positive association between sea ice and foraging activity was found for both sexes where increased biological activity may sustain an under-ice ecosystem. Variability of the East Antarctic sea ice season duration is likely a crucial element to allow air-breathing predators to benefit from profitable prey patches within the pack ice habitat. | ||||
| Programme | 109 | ||||
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| Series Volume | Series Issue | Edition | |||
| ISSN | 0079-6611 | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | Approved | yes | |||
| Call Number | Serial | 6183 | |||
| Permanent link to this record | |||||
| Author | Nathan Pacoureau, Matthieu Authier, Karine Delord, Christophe Guinet, Christophe Barbraud | ||||
| Title | Early-life density-dependence effects on growth and survival in subantarctic fur seals | Type | Journal | ||
| Year | 2017 | Publication | Population Ecology | Abbreviated Journal | |
| Volume | 59 | Issue | 2 | Pages | 139-155 |
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| Abstract |
Understanding the regulation of natural populations has been a long-standing research program in ecology. Current knowledge on marine mammals and seabirds is biased toward the adult component of populations and lacking are studies investigating the juvenile component. Our goal was to estimate demographic parameters on the pre-weaning stage of a subantarctic fur seal (Arctocephalus tropicalis) population on Amsterdam Island, suspected to be regulated by density-dependence. The influence of abundance on growth parameters (length and weight) and survival was assessed over a study period spanning 16 years. We evidenced a negative trend in population growth rate when density increased. Density-dependence models were favored for pup body size and mass growth. Abundance had a clear influence on body length at high population-density, pups grew slower and were smaller at weaning than pups born in years with low population density. Abundance partly explained pup body mass variation and a weak effect was detected on pre-weaning survival. The causal mechanisms may be increased competition for food resources between breeding females, leading to a reduction of maternal input to their pups. Our results suggested that pup favored survival over growth and the development of their diving abilities in order to withstand the extreme fasting periods that are characteristic of this fur seal population. This analysis provides significant insight of density-dependent processes on early-life demographic parameters of a long lived and top-predator species, and more specifically on the pre-weaning stage with important consequences for our understanding of individual long-term fitness and population dynamics. | ||||
| Programme | 109 | ||||
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| Series Volume | Series Issue | Edition | |||
| ISSN | 1438-3896, 1438-390X | ISBN | 1438-3896, 1438-390X | Medium | |
| Area | Expedition | Conference | |||
| Notes | Approved | yes | |||
| Call Number | Serial | 6662 | |||
| Permanent link to this record | |||||
| Author | Nathan Pacoureau, Matthieu Authier, Karine Delord, Christophe Guinet, Christophe Barbraud | ||||
| Title | Early-life density-dependence effects on growth and survival in subantarctic fur seals | Type | Journal | ||
| Year | 2017 | Publication | Population Ecology | Abbreviated Journal | |
| Volume | 59 | Issue | 2 | Pages | 139-155 |
| Keywords | Arctocephalus tropicalis Capture-mark-recapture Growth model Marine top predator Population dynamics State space model | ||||
| Abstract |
Understanding the regulation of natural populations has been a long-standing research program in ecology. Current knowledge on marine mammals and seabirds is biased toward the adult component of populations and lacking are studies investigating the juvenile component. Our goal was to estimate demographic parameters on the pre-weaning stage of a subantarctic fur seal (Arctocephalus tropicalis) population on Amsterdam Island, suspected to be regulated by density-dependence. The influence of abundance on growth parameters (length and weight) and survival was assessed over a study period spanning 16 years. We evidenced a negative trend in population growth rate when density increased. Density-dependence models were favored for pup body size and mass growth. Abundance had a clear influence on body length at high population-density, pups grew slower and were smaller at weaning than pups born in years with low population density. Abundance partly explained pup body mass variation and a weak effect was detected on pre-weaning survival. The causal mechanisms may be increased competition for food resources between breeding females, leading to a reduction of maternal input to their pups. Our results suggested that pup favored survival over growth and the development of their diving abilities in order to withstand the extreme fasting periods that are characteristic of this fur seal population. This analysis provides significant insight of density-dependent processes on early-life demographic parameters of a long lived and top-predator species, and more specifically on the pre-weaning stage with important consequences for our understanding of individual long-term fitness and population dynamics. | ||||
| Programme | 109 | ||||
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| Publisher | Place of Publication | Editor | |||
| Language | Summary Language | Original Title | |||
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 1438-390X | ISBN | 1438-390X | Medium | |
| Area | Expedition | Conference | |||
| Notes | Approved | yes | |||
| Call Number | Serial | 7174 | |||
| Permanent link to this record | |||||
| Author | Yves Cherel, Antoine Carrouée | ||||
| Title | Assessing marine ecosystem complexity: isotopic integration of the trophic structure of seabird communities from the Southern Ocean | Type | Journal | ||
| Year | 2022 | Publication | Marine Ecology Progress Series | Abbreviated Journal | |
| Volume | 694 | Issue | Pages | 193-208 | |
| Keywords | Antarctica Body size Habitat Penguins Procellariiformes Stable isotopes Trophic position | ||||
| Abstract |
Understanding the processes structuring communities is a fundamental goal in ecology and conservation biology. Seabirds are commonly used as sentinels of marine ecosystems, but there is a lack of quantitative information providing a synoptic view of their community structure and of its underlying mechanisms. We used stable isotope analysis of chick feathers to investigate the structure of 2 communities that are representative of the subantarctic (Kerguelen) and Antarctic (Adélie Land) seabird diversity. Total area of the convex hull (a measure of the total δ13C-δ15N niche space) was 8.4-fold higher at the Kerguelen Islands than in Adélie Land, a consequence of the higher seabird diversity at the former locality. Kerguelen seabirds grouped into 2 clusters of oceanic and inshore species, with the latter group not represented in Adélie Land. Communities are primarily structured by the availability of foraging habitats (δ13C) and then of trophic resources (δ15N), with body size being a major driving force of trophic position. Ecological characteristics are more important than phylogeny to shape seabird isotopic niche breadth (standard ellipse area corrected for small sample size, SEAc), with no significant differences between Sphenisciformes, Procellariiformes, and Charadriiformes. By contrast, SEAc varies according to foraging guilds, diet, and a specialist-generalist gradient, with ubiquitous seabirds having a 10-fold larger mean SEAc than pelagic divers. This study sets a baseline against which the effects of long-term environmental changes on seabird community structure can be studied across years and conditions, and provides a relevant starting point for the investigation into the effect of climate change on Southern Ocean ecosystems. | ||||
| Programme | 109 | ||||
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| Language | Summary Language | Original Title | |||
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| Series Volume | Series Issue | Edition | |||
| ISSN | 0171-8630, 1616-1599 | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | Approved | yes | |||
| Call Number | Serial | 8321 | |||
| Permanent link to this record | |||||
| Author | Lara D. Shepherd, Colin M. Miskelly, Yves Cherel, Alan J. D. Tennyson | ||||
| Title | Genetic identification informs on the distributions of vagrant Royal (Eudyptes schlegeli) and Macaroni (Eudyptes chrysolophus) Penguins | Type | Journal | ||
| Year | 2021 | Publication | Polar Biology | Abbreviated Journal | |
| Volume | 44 | Issue | 12 | Pages | 2299-2306 |
| Keywords | Antarctica Eudyptes chrysolophus Eudyptes schlegeli Genetic identification Penguin distribution Predation | ||||
| Abstract |
Understanding the movements of animals that spend much of their life at sea is difficult but important for effective conservation. Determining the at-sea distributions of Macaroni (Eudyptes chrysolophus) and Royal (Eudyptes schlegeli) Penguins poses particular challenges, including their occurrence in remote locations and difficulties in species identification owing to overlap in morphological characters, particularly in immature birds. Here we use DNA sequencing to examine vagrant Macaroni and Royal Penguins from Antarctica and New Zealand in order to improve understanding of their non-breeding distributions. Our sampling included samples from living birds, museum specimens and scavenged penguin remains recovered from the stomachs of Antarctic toothfish (Dissostichus mawsoni) caught north of the Ross Sea. Mitochondrial control region (HVRI) sequences indicated that the two samples from New Zealand were likely Royal Penguins as were the scavenged penguins. Both Macaroni and Royal Penguins were detected at Terre Adélie, Antarctica, despite the nearest breeding colony of Macaroni Penguins being 4000 km away. We provide the first evidence of Royal Penguins reaching the Ross Dependency. All but one of the vagrants were immature birds, supporting suggestions that this age group is the most likely to disperse large distances from the breeding colonies. Our study demonstrates how DNA sequences can assist in identifying taxa with similar or overlapping morphologies, as well as fragmentary bird remains. | ||||
| Programme | 109 | ||||
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| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 1432-2056 | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | Approved | yes | |||
| Call Number | Serial | 8365 | |||
| Permanent link to this record | |||||
| Author | Scarlett Boiardi | ||||
| Title | The isotopic composition of water vapour in the Svalbard and the atmospheric circulation | Type | Master | ||
| Year | 2015 | Publication | Abbreviated Journal | ||
| Volume | Issue | Pages | |||
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| Abstract |
Understanding the meteorological drivers of precipitation isotopic composition is crucial for the
interpretation of paleoclimate archives, such as the past precipitation records found in the ice cores, as well as to successfully constrain atmospheric models including the explicit representation of water isotopes. This is of particular importance in the context of climate change, and in particular in the Arctic where climate models project enhanced hydrological cycle and temperature increase which might in turn have significant impacts on the global climate (through e.g. the sea-ice retreat, water vapour feedback or cloud cover). Indeed, large discrepancies on the future Arctic precipitation exist amongst different climate models. Condensing water vapour being the first stage of a precipitation event, its isotopic composition influences that of the precipitation and must therefore be fully understood in order to find the causes for the inter-model spread. The water vapour isotopic composition is believed to be influenced by changes in moisture sources and fractionation history during transport. It thus provides valuable and independent information on moisture source origins and represents a crucial tool for assessing the realism of models and the interpretation of meteorological archives. During the last 5 years, new laser methods have permitted to achieve such measurements of water isotopes. In the present work, new in situ continuous measurements of the isotopic composition of water vapour in Svalbard between the end of June 2014 and March 2015 are studied. Given its location, Svalbard allowed us to expand the monitoring of water vapour isotopic composition and atmospheric circulation towards the Arctic so as to explore their relationship to the moisture source conditions. In order to do so, Lagrangian backtrajectories were computed and associated with the processed data. A clear distinction between trajectories coming from over the Arctic sea-ice area and those from the North Atlantic Ocean could be observed in the isotopic composition. The latter also displayed seasonal variations attributed to seasonal changes in atmospheric transport. Moreover, during days with low isotopic depletion, deviations from the expected global meteoric water line were observed and studied. Finally, days displaying a significant and rapid change in the isotopic composition were explained by a corresponding sudden change in the air mass past trajectory. This work opens the possibility to quantify the effects of evaporation conditions on isotopic data, provides a new dataset for the evaluation of atmospheric models, and will provide a basis to revise the climatic interpretation of Svalbard ice core records. |
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| Programme | 1134 | ||||
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| Notes | Approved | yes | |||
| Call Number | Serial | 6055 | |||
| Permanent link to this record | |||||
| Author | Mioara Mandea, Aude Chambodut | ||||
| Title | Geomagnetic Field Processes and Their Implications for Space Weather | Type | Journal | ||
| Year | 2020 | Publication | Surveys in Geophysics | Abbreviated Journal | |
| Volume | 41 | Issue | 6 | Pages | 1611-1627 |
| Keywords | |||||
| Abstract |
Understanding the magnetic environment of our planet and the geomagnetic field changes in time and space is a very important issue for assessing the Sun–Earth interactions. All changes in solar activity impact the delicate balance between influences of interplanetary magnetic field and of geomagnetic field. The most dynamic events eventually result in disturbances in the magnitude and direction of the Earth’s magnetic field and therefore impact our planet and its magnetosphere as a whole. The dynamics of the ionosphere and thermosphere during magnetic storms and substorms involves the heating, expansion, and composition changes at high latitudes, but also the surface-level response in terms of geomagnetically induced currents and other geomagnetic and geoelectric disturbances. Here, we provide a short overview of the current knowledge of the Earth’s magnetic field, its present shape and the way it responds to external forces. The main aim of the paper is not to present the complexity of the space weather processes, but rather to bring the attention of the geohazard community to the possible dramatic effects of space weather events. For this, the paper highlights some societal implications of space weather on our increasingly technology-dependent society, including some possible effects of geomagnetically induced currents, the disruption of satellite communications and navigation, and risks of radiation damage both in space and in aviation. | ||||
| Programme | 139 | ||||
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| Series Volume | Series Issue | Edition | |||
| ISSN | 1573-0956 | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | Approved | yes | |||
| Call Number | Serial | 7016 | |||
| Permanent link to this record | |||||