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Author (up) Jan Jansen, Piers K. Dunstan, Nicole A. Hill, Philippe Koubbi, Jessica Melbourne-Thomas, Romain Causse, Craig R. Johnson doi  openurl
  Title Integrated assessment of the spatial distribution and structural dynamics of deep benthic marine communities Type Journal
  Year 2020 Publication Ecological Applications Abbreviated Journal  
  Volume 30 Issue 3 Pages e02065  
  Keywords Antarctica continental shelf deep sea ecosystem dynamic ecosystem structure qualitative network model Southern Ocean spatial model species archetype model upper slope  
  Abstract Characterizing the spatial distribution and variation of species communities and validating these characteristics with data from the field are key elements for an ecosystem-based approach to management. However, models of species distributions that yield community structure are usually not linked to models of community dynamics, constraining understanding and management of the ecosystem, particularly in data-poor regions. Here we use a qualitative network model to predict changes in Antarctic benthic community structure between major marine habitats characterized largely by seafloor depth and slope, and use multivariate mixture models of species distributions to validate the community dynamics. We then assess how future increases in primary production associated with anticipated loss of sea-ice may affect the ecosystem. Our study shows how both spatial and structural features of ecosystems in data-poor regions can be analyzed and possible futures assessed, with direct relevance for ecosystem-based management.  
  Programme 281  
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  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1939-5582 ISBN Medium  
  Area Expedition Conference  
  Notes Approved yes  
  Call Number Serial 8263  
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Author (up) Jean-Yves Toullec, Kévin Cascella, Stéphanie Ruault, Alexandre Geffroy, David Lorieux, Nicolas Montagné, Céline Ollivaux, Chi-Ying Lee doi  openurl
  Title Antarctic krill (Euphausia superba) in a warming ocean: thermotolerance and deciphering Hsp70 responses Type Journal
  Year 2020 Publication Cell Stress and Chaperones Abbreviated Journal  
  Volume 25 Issue 3 Pages 519-531  
  Keywords  
  Abstract The Antarctic krill, Euphausia superba, is a Southern Ocean endemic species of proven ecological importance to the region. In the context of predicted global warming, it is particularly important to understand how classic biomarkers of heat stress function in this species. In this respect, Hsp70s are acknowledged as good candidates. However, previous studies of expression kinetics have not been able to demonstrate significant upregulation of these genes in response to heat shocks at 3 °C and 6 °C for 3 and 6 h. The current work complements these previous results and broadens the prospects for the use of Hsp70s as a relevant marker of thermal shock in this krill species. New experiments demonstrate that induction of Hsp70 isoforms was not detected during exposure to heat shock, but increased expression was observed after several hours of recovery. To complete the analysis of the expression kinetics of the different isoforms, experiments were carried out over short time scales (1 and 2 h at 3 °C and 6 °C) as well as at higher temperatures (9 °C, 12 °C, and 15 °C for 3 h), without any significant response. A 6-week monitoring of animals at 3 °C showed that the time factor is decisive in the establishment of the response. CTmax experiments with incremental times of 1 °C per day or 1 °C every 3 days have shown a particularly high resilience of the animals. The demonstration of the abundance of Hsp70s present before thermal stress in various species of krill, as well as in specimens of E. superba of various origins, showed that the delay in the response in expression could be related to the high constitutive levels of Hsp70 available before the stress experiments. The alternative labelling of the two main isoforms of Hsp70 according to the origin of the animals allowed hypotheses to be put forward on the functioning of thermoregulation in Antarctic krill as well as ice krill.  
  Programme 1039  
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  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1466-1268 ISBN Medium  
  Area Expedition Conference  
  Notes Approved yes  
  Call Number Serial 8173  
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Author (up) Jeroen Reneerkens, Tom S. L. Versluijs, Theunis Piersma, José A. Alves, Mark Boorman, Colin Corse, Olivier Gilg, Gunnar Thor Hallgrimsson, Johannes Lang, Bob Loos, Yaa Ntiamoa‐Baidu, Alfred A. Nuoh, Peter M. Potts, Job ten Horn, Tamar Lok doi  openurl
  Title Low fitness at low latitudes: Wintering in the tropics increases migratory delays and mortality rates in an Arctic breeding shorebird Type Journal
  Year 2020 Publication Journal of Animal Ecology Abbreviated Journal  
  Volume 89 Issue 3 Pages 691-703  
  Keywords demography fitness migration nutrient storage strategies site fidelity solar geolocation survival timing  
  Abstract Evolutionary theories of seasonal migration generally assume that the costs of longer migrations are balanced by benefits at the non-breeding destinations. We tested, and rejected, the null hypothesis of equal survival and timing of spring migration for High Arctic breeding sanderling Calidris alba using six and eight winter destinations between 55°N and 25°S, respectively. Annual apparent survival was considerably lower for adult birds wintering in tropical West Africa (Mauritania: 0.74 and Ghana: 0.75) than in three European sites (0.84, 0.84 and 0.87) and in subtropical Namibia (0.85). Moreover, compared with adults, second calendar-year sanderlings in the tropics, but not in Europe, often refrained from migrating north during the first possible breeding season. During northward migration, tropical-wintering sanderlings occurred at their final staging site in Iceland 5–15 days later than birds wintering further north or south. Namibia-wintering sanderlings tracked with solar geolocators only staged in West Africa during southward migration. The low annual survival, the later age of first northward migration and the later passage through Iceland during northward migration of tropical-wintering sanderlings, in addition to the skipping of this area during northward but not southward migration by Namibia-wintering sanderlings, all suggest they face issues during the late non-breeding season in West Africa. Migrating sanderlings defy long distances but may end up in winter areas with poor fitness prospects. We suggest that ecological conditions in tropical West Africa make the fuelling prior to northward departure problematic.  
  Programme 1036  
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  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1365-2656 ISBN Medium  
  Area Expedition Conference  
  Notes Approved yes  
  Call Number Serial 7690  
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Author (up) Jouanneau W, Léandri-Breton DJ, Moe B, Parenteau C, Herzke D, Elliott K, Gabrielsen GW, Chastel O openurl 
  Title Transfert maternel de contaminants et perturbation endocrine chez un oiseau marin Arctique Type Peer-reviewed symposium
  Year 2020 Publication 16émes journées scientifiques du CNFRA, 22-23 septembre 2020, La Rochelle, France Abbreviated Journal  
  Volume Issue Pages  
  Keywords  
  Abstract  
  Programme 330  
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  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN ISBN Medium  
  Area Expedition Conference  
  Notes Approved yes  
  Call Number Serial 8046  
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Author (up) Juliana A. Vianna, Flávia A. N. Fernandes, María José Frugone, Henrique V. Figueiró, Luis R. Pertierra, Daly Noll, Ke Bi, Cynthia Y. Wang-Claypool, Andrew Lowther, Patricia Parker, Celine Le Bohec, Francesco Bonadonna, Barbara Wienecke, Pierre Pistorius, Antje Steinfurth, Christopher P. Burridge, Gisele P. M. Dantas, Elie Poulin, W. Brian Simison, Jim Henderson, Eduardo Eizirik, Mariana F. Nery, Rauri C. K. Bowie file  doi
openurl 
  Title Genome-wide analyses reveal drivers of penguin diversification Type Journal
  Year 2020 Publication Proceedings of the National Academy of Sciences Abbreviated Journal  
  Volume 117 Issue 36 Pages 22281-22292  
  Keywords ancestral distribution ancestral niche Antarctica genome penguin  
  Abstract Penguins are the only extant family of flightless diving birds. They currently comprise at least 18 species, distributed from polar to tropical environments in the Southern Hemisphere. The history of their diversification and adaptation to these diverse environments remains controversial. We used 22 new genomes from 18 penguin species to reconstruct the order, timing, and location of their diversification, to track changes in their thermal niches through time, and to test for associated adaptation across the genome. Our results indicate that the penguin crown-group originated during the Miocene in New Zealand and Australia, not in Antarctica as previously thought, and that Aptenodytes is the sister group to all other extant penguin species. We show that lineage diversification in penguins was largely driven by changing climatic conditions and by the opening of the Drake Passage and associated intensification of the Antarctic Circumpolar Current (ACC). Penguin species have introgressed throughout much of their evolutionary history, following the direction of the ACC, which might have promoted dispersal and admixture. Changes in thermal niches were accompanied by adaptations in genes that govern thermoregulation and oxygen metabolism. Estimates of ancestral effective population sizes (Ne) confirm that penguins are sensitive to climate shifts, as represented by three different demographic trajectories in deeper time, the most common (in 11 of 18 penguin species) being an increased Ne between 40 and 70 kya, followed by a precipitous decline during the Last Glacial Maximum. The latter effect is most likely a consequence of the overall decline in marine productivity following the last glaciation.  
  Programme 137,354  
  Campaign  
  Address  
  Corporate Author Thesis Bachelor's thesis  
  Publisher Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0027-8424, 1091-6490 ISBN Medium  
  Area Expedition Conference  
  Notes Approved yes  
  Call Number Serial 7780  
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Author (up) Julie Mestre, Matthieu Authier, Yves Cherel, Rob Harcourt, Clive R. McMahon, Mark A. Hindell, Jean-Benoît Charrassin, Christophe Guinet file  doi
openurl 
  Title Decadal changes in blood δ13C values, at-sea distribution, and weaning mass of southern elephant seals from Kerguelen Islands Type Journal
  Year 2020 Publication Proceedings of the Royal Society B: Biological Sciences Abbreviated Journal  
  Volume 287 Issue 1933 Pages 20201544  
  Keywords bio-logging decadal change foraging habitat Indian sector of the Southern Ocean population strategies stable isotopes  
  Abstract Changes in the foraging environment and at-sea distribution of southern elephant seals from Kerguelen Islands were investigated over a decade (2004–2018) using tracking, weaning mass, and blood δ13C values. Females showed either a sub-Antarctic or an Antarctic foraging strategy, and no significant shift in their at-sea distribution was detected between 2004 and 2017. The proportion of females foraging in sub-Antarctic versus Antarctic habitats did not change over the 2006–2018 period. Pup weaning mass varied according to the foraging habitat of their mothers. The weaning mass of sub-Antarctic foraging mothers' pups decreased by 11.7 kg over the study period, but they were on average 5.8 kg heavier than pups from Antarctic foraging mothers. Pup blood δ13C values decreased by 1.1‰ over the study period regardless of their sex and the presumed foraging habitat of their mothers. Together, these results suggest an ecological change is occurring within the Indian sector of the Southern Ocean with possible consequences on the foraging performance of southern elephant seals. We hypothesize that this shift in δ13C is related to a change in primary production and/or in the composition of phytoplankton communities, but this requires further multidisciplinary investigations.  
  Programme 109,1201  
  Campaign  
  Address  
  Corporate Author Thesis Bachelor's thesis  
  Publisher Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN ISBN Medium  
  Area Expedition Conference  
  Notes Approved yes  
  Call Number Serial 8006  
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Author (up) Julie Sansoulet, Michèle Therrien, Joseph Delgove, Guilhem Pouxviel, Julie Desriac, Noé Sardet, Jean-Paul Vanderlinden doi  isbn
openurl 
  Title An update on Inuit perceptions of their changing environment, Qikiqtaaluk (Baffin Island, Nunavut) Type Journal
  Year 2020 Publication Elementa: Science of the Anthropocene Abbreviated Journal  
  Volume 8 Issue 1 Pages  
  Keywords  
  Abstract The Inuit of Qikiqtaaluk (Baffin Island) have developed a deep respect for their natural environment and are able to report not only changes in weather, ice, and natural resources but also changes in their communities as a result of climate change. The objective of this study was to shed light on how the impacts of climate change are currently perceived in the communities of Kanngiqtugaapik, Pangniqtuuq, and Qikiqtarjuaq. In order to construct a shared knowledge base, we conducted qualitative video interviews and participated in a hunting camp with multigenerational and multigender Inuit hunters and fishers. First, Inuit continue to see the world in which they cohabit with other living things, particularly animals, as a world that they cannot control on their own—a world they must adapt to, passing learning from one generation to the next. Second, they report that changes in the ice have been among the major and most important transformations to have occurred in recent decades. Observations made by these local populations also indicate changes in hunted species, with fewer caribou and narwhal, more birds, insects, and fish, including from more southerly regions, and an uncertainty about polar bear populations. Seal hunting remains stable, and this meat is still the most popular and healthy food, physically and psychologically. Third, sociological and economic changes (e.g., lifestyle change, monetary economies, quotas), in addition to environmental changes (e.g., climate change, species change), have had a significant impact on food harvesting activities as well as food consumption in the region. A final perspective concerns the needs of the Qikiqtaaluk communities to further develop collaboration with scientists. This need for partnership is not only perceived as a scientific necessity but also recognized by Inuit as essential to their communities, with some local leaders ready to work toward a fruitful collaboration.  
  Programme 1164  
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  Corporate Author Thesis  
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  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2325-1026 ISBN 2325-1026 Medium  
  Area Expedition Conference  
  Notes Approved yes  
  Call Number Serial 8117  
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Author (up) Julien Collet, Henri Weimerskirch doi  openurl
  Title Albatrosses can memorize locations of predictable fishing boats but favour natural foraging Type Journal
  Year 2020 Publication Proceedings of the royal society b: biological sciences Abbreviated Journal  
  Volume 287 Issue 1932 Pages 20200958  
  Keywords albatrosses anthropogenic food cognition in the wild fisheries individual consistency resource predictability  
  Abstract Human activities generate food attracting many animals worldwide, causing major conservation issues. The spatio-temporal predictability of anthropogenic resources could reduce search costs for animals and mediate their attractiveness. We investigated this through GPS tracking in breeding black-browed albatrosses attracted to fishing boats. We tested for answers to the following questions. (i) Can future boat locations be anticipated from cues available to birds? (ii) Are birds able to appropriately use these cues to increase encounters? (iii) How frequently do birds use these cues? Boats were spatially persistent: birds searching in the direction where they previously attended boats would encounter twice as many boats compared with following a random direction strategy. A large proportion of birds did not use this cue: across pairs of consecutive trips (n = 85), 51% of birds switched their foraging direction irrespective of previous boat encounters. Still, 15 birds (27%) were observed to closely approach (approx. 0.1–1 km) where they previously attended a boat while boats were no longer there. This is less than the distance expected by chance (approx. 10–100 km), based on permutation control procedures accounting for individual-specific spatial consistency, suggesting individuals could memorize where they encountered boats across consecutive trips. We conclude albatrosses were able to exploit predictive cues from recent boat encounters but most favoured alternative resources.  
  Programme 109  
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  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN ISBN Medium  
  Area Expedition Conference  
  Notes Approved yes  
  Call Number Serial 8074  
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Author (up) Kévin Fourteau, Fabien Gillet-Chaulet, Patricia Martinerie, Xavier Faïn doi  openurl
  Title A Micro-Mechanical Model for the Transformation of Dry Polar Firn Into Ice Using the Level-Set Method Type Journal
  Year 2020 Publication Frontiers in Earth Science Abbreviated Journal  
  Volume 8 Issue Pages 101  
  Keywords  
  Abstract Interpretation of greenhouse gas records in polar ice cores requires a good understanding of the mechanisms controlling gas trapping in polar ice, and therefore of the processes of densification and pore closure in firn (compacted snow). Current firn densification models are based on a macroscopic description of the firn and rely on empirical laws and/or idealized geometries to obtain the equations governing the densification and pore closure. Here, we propose a physically-based methodology explicitly representing the porous structure and its evolution over time. In order to handle the complex geometry and topological changes that occur during firn densification, we rely on a Level-Set representation of the interface between the ice and the pores. Two mechanisms are considered for the displacement of the interface: (i) mass surface diffusion driven by local pore curvature and (ii) ice dislocation creep. For the latter, ice is modeled as a viscous material and the flow velocities are solutions of the Stokes equations. First applications show that the model is able to densify firn and split pores. Using the model in cold and arid conditions of the Antarctic plateau, we show that gas trapping models do not have to consider the reduced compressibility of closed pores compared to open pores in the deepest part of firns. Our results also suggest that the mechanism of curvature-driven surface diffusion does not result in pore splitting, and that ice creep has to be taken into account for pores to close. Future applications of this type of model could help quantify the evolution and closure of firn porous networks for various accumulation and temperature conditions.  
  Programme 1153  
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  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2296-6463 ISBN Medium  
  Area Expedition Conference  
  Notes Approved yes  
  Call Number Serial 8268  
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Author (up) Korbinian Sager, Christian Boehm, Laura Ermert, Lion Krischer, Andreas Fichtner doi  openurl
  Title Global-Scale Full-Waveform Ambient Noise Inversion Type Journal
  Year 2020 Publication Journal of Geophysical Research: Solid Earth Abbreviated Journal  
  Volume 125 Issue 4 Pages e2019JB018644  
  Keywords computational seismology full-waveform inversion global tomography interferometry seismic noise  
  Abstract We present the first application of full-waveform ambient noise inversion to observed correlation functions that jointly constrains 3-D Earth structure and heterogeneous noise sources. For this, we model and interpret ambient noise correlations as recordings of correlation wavefields, which completely eliminates the limiting assumptions of Green's function retrieval, such as equipartitioning and homogeneous random noise sources. Our method accounts for seismic wave propagation physics in 3-D heterogeneous and attenuating media and also for the heterogeneous and nonstationary nature of the ambient noise field. Designed as a proof of concept, the study considers long periods from 100 to 300 s, thus focusing on the Earth's hum. Treating correlations as self-consistent observables allows us to make separate measurements on the causal and acausal branches of correlation functions, without any need to choose one of them or form the average. We validate our approach by assessing the quality of the obtained models and by comparing them to previous studies. This work is a step toward the establishment of full-waveform ambient noise inversion as a tomographic technique with the goal to go beyond ambient noise tomography based on Green's function retrieval.  
  Programme 133  
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  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2169-9356 ISBN Medium  
  Area Expedition Conference  
  Notes Approved yes  
  Call Number Serial 7794  
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