|   | 
Details
   web
Records
Author Morgane Amelot, Floriane Plard, Christophe Guinet, John P. Y. Arnould, Nicolas Gasco, Paul Tixier
Title Increasing numbers of killer whale individuals use fisheries as feeding opportunities within subantarctic populations Type Journal
Year (down) 2022 Publication Biology Letters Abbreviated Journal
Volume 18 Issue 2 Pages 20210328
Keywords capture–mark–recapture depredation killer whales
Abstract Fisheries can generate feeding opportunities for large marine predators in the form of discards or accessible catch. How the use of this anthropogenic food may spread as a new behaviour, across individuals within populations over time, is poorly understood. This study used a 16-year (2003–2018) monitoring of two killer whale Orcinus orca subantarctic populations (regular and Type-D at Crozet), and Bayesian multistate capture–mark–recapture models, to assess temporal changes in the number of individuals feeding on fish caught on hooks (‘depredation’ behaviour) of a fishery started in 1996. For both populations, the number of depredating individuals increased during the study period (34 to 94 for regular; 17 to 43 for Type-D). Increasing abundance is unlikely to account for this and, rather, the results suggest depredation was acquired by increasing numbers of existing individuals. For regular killer whales, a plateau reached from 2014 suggests that it took 18 years for the behaviour to spread across the whole population. A more recent plateau was apparent for Type-Ds but additional years are needed to confirm this. These findings show how changes in prey availability caused by human activities lead to rapid, yet progressive, innovations in killer whales, likely altering the ecological role of this top-predator.
Programme 109
Campaign
Address
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 8378
Permanent link to this record
 

 
Author Natasja Krog Noer, Mathias Hamann Sørensen, Hervé Colinet, David Renault, Simon Bahrndorff, Torsten Nygaard Kristensen
Title Rapid Adjustments in Thermal Tolerance and the Metabolome to Daily Environmental Changes – A Field Study on the Arctic Seed Bug Nysius groenlandicus Type Journal
Year (down) 2022 Publication Frontiers in physiology Abbreviated Journal
Volume 13 Issue Pages
Keywords
Abstract Laboratory investigations on terrestrial model-species, typically of temperate origin, have demonstrated that terrestrial ectotherms can cope with daily temperature variations through rapid hardening responses. However, few studies have investigated this ability and its physiological basis in the field. Especially in polar regions, where the temporal and spatial temperature variations can be extreme, are hardening responses expected to be important. Here, we examined diurnal adjustments in heat and cold tolerance in the Greenlandic seed bug Nysius groenlandicus by collecting individuals for thermal assessment at different time points within and across days. We found a significant correlation between observed heat or cold tolerance and the ambient microhabitat temperatures at the time of capture, indicating that N. groenlandicus continuously and within short time-windows respond physiologically to thermal changes and/or other environmental variables in their microhabitats. Secondly, we assessed underlying metabolomic fingerprints using GC-MS metabolomics in a subset of individuals collected during days with either low or high temperature variation. Concentrations of metabolites, including sugars, polyols, and free amino acids varied significantly with time of collection. For instance, we detected elevated sugar levels in animals caught at the lowest daily field temperatures. Polyol concentrations were lower in individuals collected in the morning and evening and higher at midday and afternoon, possibly reflecting changes in temperature. Additionally, changes in concentrations of metabolites associated with energetic metabolism were observed across collection times. Our findings suggest that in these extreme polar environments hardening responses are marked and likely play a crucial role for coping with microhabitat temperature variation on a daily scale, and that metabolite levels are actively altered on a daily basis.
Programme 136
Campaign
Address
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 1664-042X ISBN Medium
Area Expedition Conference
Notes Approved yes
Call Number Serial 8479
Permanent link to this record
 

 
Author Nicolas Cortiade, Adélie Delacour, Damien Guillaume, Bertrand Moine, June Chevet
Title Serpentinization of mantle xenoliths in Kerguelen archipelago: A first petrographic and geochemical study Type Journal
Year (down) 2022 Publication Lithos Abbreviated Journal
Volume 428-429 Issue Pages 106796
Keywords Fluid composition Fluid origin Kerguelen Mantle xenoliths Serpentinization
Abstract The spinel harzburgites xenoliths from the Lac Michèle outcrop, Kerguelen archipelago (South Indian Ocean), have the particularity to show unique and unusual evidences of fluids circulation and especially of serpentinization. In this paper, in situ and whole-rock petrographic and geochemical data on a selection of variously serpentinized samples are presented and attest that several episodes of fluid-rock interaction occurred. Serpentinization processes affected notably and with variable degrees the spinel harzburgites leading to changes in their mineralogy and chemical compositions. Degree of serpentinization ranges from very slight (LOI < 3 wt% and Fe3+/Fetot < 0.1) to moderate (4 wt% < LOI < 6 wt% and 0.21 < Fe3+/Fetot < 0.33). Most serpentinized samples show a preferential petrographic direction of serpentinization, forming a subparallel serpentine network, which is sometimes intersected by serpentine veins. As a result, at least two serpentinization episodes were identified within the Lac Michèle samples, without any chemical differences between the two generations except for Cl content. This suggests very few chemical evolution of the system during serpentinization. Due to the significant amount of Cl measured in serpentine minerals (601 ppm on average), the nature of the fluids that interacted with the spinel harzburgites xenoliths during the serpentinization events can be hypothesized to be seawater-like or seawater-derived fluids.
Programme 1077
Campaign
Address
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 0024-4937 ISBN Medium
Area Expedition Conference
Notes Approved yes
Call Number Serial 8587
Permanent link to this record
 

 
Author Nicolas J. Rawlence, Alexander T. Salis, Hamish G. Spencer, Jonathan M. Waters, Lachie Scarsbrook, Kieren J. Mitchell, Richard A. Phillips, Luciano Calderón, Timothée R. Cook, Charles-André Bost, Ludovic Dutoit, Tania M. King, Juan F. Masello, Lisa J. Nupen, Petra Quillfeldt, Norman Ratcliffe, Peter G. Ryan, Charlotte E. Till, Martyn Kennedy
Title Rapid radiation of Southern Ocean shags in response to receding sea ice Type Journal
Year (down) 2022 Publication Journal of Biogeography Abbreviated Journal
Volume 49 Issue 5 Pages 942-953
Keywords biogeography climate cycles cormorant Leucocarbo Southern Ocean speciation sub-Antarctic
Abstract Aim Understanding how natural populations respond to climatic shifts is a fundamental goal of biological research in a fast-changing world. The Southern Ocean represents a fascinating system for assessing large-scale climate-driven biological change, as it contains extremely isolated island groups within a predominantly westerly, circumpolar wind and current system. Blue-eyed shags represent a paradoxical seabird radiation—a circumpolar distribution implies strong dispersal capacity yet their species-rich nature suggests local adaptation and isolation. Here we attempt to resolve this paradox in light of the history of repeated cycles of climate change in the Southern Ocean. Location Southern Ocean. Taxa 16 species and subspecies of blue-eyed shags (Phalacrocoracidae; Leucocarbo spp.). Methods We use mitochondrial and nuclear sequence data from individuals across the geographical range of the genus to conduct the first comprehensive, time-calibrated phylogenetic analyses and ancestral-range biogeographical reconstructions of the blue-eyed shags. Results The origins of many island-endemic lineages are remarkably recent, consistent with a recent high-latitude circumpolar radiation in the Pliocene or Early Pleistocene. This recent sub-Antarctic expansion contrasts with significantly deeper lineages detected in South America and, to a lesser extent, New Zealand. These regions, particularly South America, acted as glacial refugia and sources for multiple waves of post-glacial dispersal. Main conclusions The blue-eyed shag paradox is resolved, with at least two waves of dispersal, linked to interglacial cycles, explaining the current distribution and diversity. Descendants of a Pliocene or Early Pleistocene wave of dispersal out of South America survive in the New Zealand region. In contrast, taxa distributed on sub-Antarctic islands originated much later, possibly since the Last Glacial Maximum. Blue-eyed shags therefore represent a powerful model system—comprising several natural replicates—for studying the early stages of founder-event speciation and adaptation in a Southern-Ocean bird group.
Programme 394
Campaign
Address
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 1365-2699 ISBN 1365-2699 Medium
Area Expedition Conference
Notes Approved yes
Call Number Serial 8456
Permanent link to this record
 

 
Author Niels Martin Schmidt, Tomas Roslin, Lars Holst Hansen, Olivier Gilg, Johannes Lang, Benoit Sittler, Jannik Hansen, Loïc Bollache, Eero Vesterinen
Title Spatio-temporal patterns in arctic fox (Vulpes alopex) diets revealed by molecular analysis of scats from Northeast Greenland Type Journal
Year (down) 2022 Publication Polar Science Abbreviated Journal
Volume 32 Issue Pages 100838
Keywords Greenland Metabarcoding Predation Trophic interactions Tundra
Abstract The arctic fox (Vulpes lagopus) is endemic to the Arctic where it holds a central position in the trophic interactions. The diet of the species has previously been described as being highly flexible, but whether this flexibility is a constant trait through time, or merely reflects fast temporal changes in abundance among prey taxa, has so far been poorly resolved. Using molecular analyses of arctic fox scats from Northeast Greenland, we first examined the temporal dynamics of arctic fox diets during the short snow-free season, and then examined whether local food availability at different sites affected arctic fox dependence on lemmings. Arctic fox diets included most terrestrial vertebrate species found in the region, and exhibited substantial temporal changes, generally reflecting the dynamic changes in prey availability from late winter through autumn. This dietary flexibility was also reflected geographically, with arctic foxes consuming a variety of local prey (mainly waterfowl and lemmings) in summer. Moreover, the dietary response of arctic foxes to changes in lemming abundance depended on access to non-lemming prey. Based on these findings, we discuss whether varying degrees of lemming-dependency, combined with geographical differences in winter food availability, may explain previously published differences in arctic fox breeding patterns in high arctic Greenland.
Programme 1036
Campaign
Address
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 1873-9652 ISBN Medium
Area Expedition Conference
Notes Approved yes
Call Number Serial 8406
Permanent link to this record
 

 
Author O. I. Berngardt, J.-P. St- Maurice, J. M. Ruohoniemi, A. Marchaudon
Title Seasonal and Diurnal Dynamics of Radio Noise for 8–20 MHz Poleward-Oriented Mid-Latitude Radars Type Journal
Year (down) 2022 Publication Radio Science Abbreviated Journal
Volume 57 Issue 9 Pages e2021RS007338
Keywords HF radars ionospheric absorption noise quiet-day curve radiowave propagation
Abstract Based on ray tracing in a smooth ionosphere described by the IRI-2012 model we have inferred the seasonal-diurnal dynamics of radio noise observed by four mid-latitude high-frequency (HF) radars. In the calculations, noise is assumed to be homogeneous and stationary, but the main contribution comes from the radar skip zone boundary due to focusing radiowaves effect. Noise absorption along the ray path is simulated from the IRI-2012 electron density, and from the molecular nitrogen density and electron temperatures obtained from the NRLMSISE-00 model. Earth magnetic field is not taken into account both in the absorption and ray-tracing calculations due to insufficient accuracy of the ionospheric model. The model results are compared with experimental radar data, and good agreement between the two is demonstrated. It is shown that experimentally observed seasonal and diurnal dynamics of the noise correlates well with model predictions. We demonstrated saturation effect at low noise levels. The model makes it possible to estimate the amount of absorption in D- and E-layers using noise observations at SuperDARN and SuperDARN-like poleward-oriented radars, especially at mid-latitudes. This is important for the retrieval of long term variations in the electron density in the lower ionosphere, by using wide coverage provided by these radars' network. The model also makes it feasible to interpret vertical absorption by experimental noise observations, thereby significantly expanding the capability of HF radars to monitor the lower ionosphere, and to provide data for joint analysis with other data, obtained by these radars at E- and F-layer heights.
Programme 312
Campaign
Address
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 1944-799X ISBN Medium
Area Expedition Conference
Notes Approved yes
Call Number Serial 8075
Permanent link to this record
 

 
Author O. P. Mishra
Title Seismo-Geophysical Studies in the Antarctic Region: Geodynamical Implications Type Journal
Year (down) 2022 Publication Assessing the Antarctic Environment from a Climate Change Perspective: An Integrated Approach Abbreviated Journal
Volume Issue Pages 287-341
Keywords Geodynamics Glacial dynamics GMCIE Plate reconstruction Seismic potential Seismo-geophysical structures Seismogenesis The Antarctic WARS
Abstract Conduction of integrated seismo-geophysical studies in the Antarctic region is a challenge as well as very much warranted to explore the region for its better geo-scientific understanding. Seismogenesis and seismic potential of the Antarctic region have not yet been well understood because of lack of common consensus on various issues, besides its unique and complex geotectonic settings associated with intriguing landscape evolution of the Antarctic plate since the breakup of Gondwana, West Antarctic Rift System (WARS), different patterns of exhumation events that occurred between the Early Cretaceous and Cenozoic. The hostile climatic situation and inaccessibility of the region due to the huge spatial distribution of thicker ice sheets hindered the mission of conducting comprehensive seismo-geophysical studies for the Antarctic Peninsula due to severe constraints of installations of ground-based sophisticated seismo-geophysical equipments in the region. Several causative factors associated with natural and anthropogenic are found still enigmatic in the sense to unravel the fact how the genesis of earthquakes are related to the glacial-dynamics and glacial mass change-induced earthquakes (GMCIE). It has become important to decipher the role and contribution of the East and the West Antarctic microplates and West Antarctic rift systems (WARS) in seismogenesis using advanced methodologies of geosciences. Seismicity of the Antarctic continent region is confined to different tectonic blocks, distributed into the southern ocean, continental margin, Lutzow-Holm Bay, Antarctic Peninsula, and in the volcanic regions in and around Deception Island, which helped estimate the seismic structure of Antarctica. In this chapter, a comprehensive overview of seismo-geophysical studies has been made to understand seismo-geodynamical implications for the Antarctic region in light of the Plate Reconstruction and seismo-geophysical structures of Antarctica.
Programme 133
Campaign
Address
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 978-3-030-87078-2 Medium
Area Expedition Conference
Notes Approved yes
Call Number Serial 8432
Permanent link to this record
 

 
Author Oihana Boudreau
Title Mise en place d’un catalogage des métadonnées et données environnementales et de biodiversité polaire Type Master 1
Year (down) 2022 Publication Rapport de stage de master 1, université de rennes 1 (encadrement : d. renault, r. georges)  Abbreviated Journal
Volume Issue Pages
Keywords
Abstract
Programme 136
Campaign
Address
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 8452
Permanent link to this record
 

 
Author Ole Richter, David E. Gwyther, Benjamin K. Galton-Fenzi, Kaitlin A. Naughten
Title The Whole Antarctic Ocean Model (WAOM v1.0): development and evaluation Type Journal
Year (down) 2022 Publication Geoscientific Model Development Abbreviated Journal
Volume 15 Issue 2 Pages 617-647
Keywords
Abstract The Regional Ocean Modeling System (ROMS), including an ice shelf component, has been applied on a circum-Antarctic domain to derive estimates of ice shelf basal melting. Significant improvements made compared to previous models of this scale are the inclusion of tides and a horizontal spatial resolution of 2 km, which is sufficient to resolve on-shelf heat transport by bathymetric troughs and eddy-scale circulation. We run the model with ocean–atmosphere–sea ice conditions from the year 2007 to represent nominal present-day climate. We force the ocean surface with buoyancy fluxes derived from sea ice concentration observations and wind stress from ERA-Interim atmospheric reanalysis. Boundary conditions are derived from the ECCO2 ocean state estimate; tides are incorporated as sea surface height and barotropic currents at the open boundary. We evaluate model results using satellite-derived estimates of ice shelf melting and established compilations of ocean hydrography. The Whole Antarctic Ocean Model (WAOM v1.0) qualitatively captures the broad scale difference between warm and cold regimes as well as many of the known characteristics of regional ice–ocean interaction. We identify a cold bias for some warm-water ice shelves and a lack of high-salinity shelf water (HSSW) formation. We conclude that further calibration and development of our approach are justified. At its current state, the model is ideal for addressing specific, process-oriented questions, e.g. related to tide-driven ice shelf melting at large scales.
Programme 688
Campaign
Address
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 1991-959X ISBN Medium
Area Expedition Conference
Notes Approved yes
Call Number Serial 8597
Permanent link to this record
 

 
Author Olivier Chastel, Jérôme Fort, Joshua T. Ackerman, Céline Albert, Frédéric Angelier, Niladri Basu, Pierre Blévin, Maud Brault-Favrou, Jan Ove Bustnes, Paco Bustamante, Jóhannis Danielsen, Sébastien Descamps, Rune Dietz, Kjell Einar Erikstad, Igor Eulaers, Alexey Ezhov, Abram B. Fleishman, Geir W. Gabrielsen, Maria Gavrilo, Grant Gilchrist, Olivier Gilg, Sindri Gíslason, Elena Golubova, Aurélie Goutte, David Grémillet, Gunnar T. Hallgrimsson, Erpur S. Hansen, Sveinn Are Hanssen, Scott Hatch, Nicholas P. Huffeldt, Dariusz Jakubas, Jón Einar Jónsson, Alexander S. Kitaysky, Yann Kolbeinsson, Yuri Krasnov, Robert J. Letcher, Jannie F. Linnebjerg, Mark Mallory, Flemming Ravn Merkel, Børge Moe, William J. Montevecchi, Anders Mosbech, Bergur Olsen, Rachael A. Orben, Jennifer F. Provencher, Sunna B. Ragnarsdottir, Tone K. Reiertsen, Nora Rojek, Marc Romano, Jens Søndergaard, Hallvard Strøm, Akinori Takahashi, Sabrina Tartu, Thorkell L. Thórarinsson, Jean-Baptiste Thiebot, Alexis P. Will, Simon Wilson, Katarzyna Wojczulanis-Jakubas, Glenn Yannic
Title Mercury contamination and potential health risks to Arctic seabirds and shorebirds Type Journal
Year (down) 2022 Publication Science of The Total Environment Abbreviated Journal
Volume 844 Issue Pages 156944
Keywords Arctic Birds Mercury Toxicity benchmarks Toxicological effects
Abstract Since the last Arctic Monitoring and Assessment Programme (AMAP) effort to review biological effects of mercury (Hg) on Arctic biota in 2011 and 2018, there has been a considerable number of new Arctic bird studies. This review article provides contemporary Hg exposure and potential health risk for 36 Arctic seabird and shorebird species, representing a larger portion of the Arctic than during previous AMAP assessments now also including parts of the Russian Arctic. To assess risk to birds, we used Hg toxicity benchmarks established for blood and converted to egg, liver, and feather tissues. Several Arctic seabird populations showed Hg concentrations that exceeded toxicity benchmarks, with 50 % of individual birds exceeding the “no adverse health effect” level. In particular, 5 % of all studied birds were considered to be at moderate or higher risk to Hg toxicity. However, most seabirds (95 %) were generally at lower risk to Hg toxicity. The highest Hg contamination was observed in seabirds breeding in the western Atlantic and Pacific Oceans. Most Arctic shorebirds exhibited low Hg concentrations, with approximately 45 % of individuals categorized at no risk, 2.5 % at high risk category, and no individual at severe risk. Although the majority Arctic-breeding seabirds and shorebirds appeared at lower risk to Hg toxicity, recent studies have reported deleterious effects of Hg on some pituitary hormones, genotoxicity, and reproductive performance. Adult survival appeared unaffected by Hg exposure, although long-term banding studies incorporating Hg are still limited. Although Hg contamination across the Arctic is considered low for most bird species, Hg in combination with other stressors, including other contaminants, diseases, parasites, and climate change, may still cause adverse effects. Future investigations on the global impact of Hg on Arctic birds should be conducted within a multi-stressor framework. This information helps to address Article 22 (Effectiveness Evaluation) of the Minamata Convention on Mercury as a global pollutant.
Programme 330,388,1036,1210
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 0048-9697 ISBN Medium
Area Expedition Conference
Notes Approved yes
Call Number Serial 8388
Permanent link to this record