Legrand M, Preunkert S, Jourdain B, Galle H, Goutail F, Weller R, Savarino J, . (2009). Year-round record of surface ozone at coastal (Dumont d'Urville) and inland (Concordia) sites in East Antarctica
. J. Geophys. Res., 114(D20), D20306–.
Keywords: Ozone, Antarctica, 0365 Atmospheric Composition and Structure: Troposphere: composition and chemistry, 0368 Atmospheric Composition and Structure: Troposphere: constituent transport and chemistry, 0330 Atmospheric Composition and Structure: Geochemical cycles,
Programme: 414;903;904;1011
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. (2009). Are stress hormone levels a good proxy of foraging success? An experiment with king penguins, Aptenodytes patagonicus.
. J. Exp. Biol., 212(17), 2824–9.
Abstract: In seabirds, variations in stress hormone (corticosterone; henceforth CORT) levels have been shown to reflect changing marine conditions and, especially, changes in food availability. However, it remains unclear how CORT levels can be mechanistically affected by these changes at the individual level. Specifically, the influence of food acquisition and foraging success on CORT secretion is poorly understood. In this study, we tested whether food acquisition can reduce baseline CORT levels (;the food intake hypothesis') by experimentally reducing foraging success of King Penguins (Aptenodytes patagonicus). Although CORT levels overall decreased during a foraging trip, CORT levels did not differ between experimental birds and controls. These results demonstrate that mass gain at sea is not involved in changes in baseline CORT levels in this species. The overall decrease in CORT levels during a foraging trip could result from CORT-mediated energy regulation (;the energy utilisation hypothesis'). Along with other evidence, we suggest that the influence of foraging success and food intake on CORT levels is complex and that the ecological meaning of baseline CORT levels can definitely vary between species and ecological contexts. Therefore, further studies are needed to better understand (1) how baseline CORT levels are functionally regulated according to energetic status and energetic demands and (2) to what extent CORT can be used to aid in the conservation of seabird populations.
Keywords: Animals, Body Composition, Corticosterone, Corticosterone: blood, Eating, Feeding Behavior, Female, Male, Spheniscidae, Spheniscidae: anatomy & histology, Spheniscidae: metabolism, Spheniscidae: physiology,
Programme: 109;394
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Loots Christophe, Swadling Kerrie M, Koubbi Philippe, . (2009). Journal of Marine Systems, 78(4), 599–605.
Keywords: Paralabidocera antarctica, Drescheriella glacialis, Stephos longipes, Southern Ocean, Sea ice, Life cycles,
Programme: 1142
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. (2011). Metabolic rate throughout the annual cycle reveals the demands of an Arctic existence in Great Cormorants
. Ecology, 92(2), 475–486.
Abstract: Aquatic endotherms living in polar regions are faced with a multitude of challenges, including low air and water temperatures and low illumination, especially in winter. Like other endotherms from cold environments, Great Cormorants (Phalacrocorax carbo) living in Arctic waters were hypothesized to respond to these challenges through a combination of high daily rate of energy expenditure (DEE) and high food requirements, which are met by a high rate of catch per unit effort (CPUE). CPUE has previously been shown in Great Cormorants to be the highest of any diving bird. In the present study, we tested this hypothesis by making the first measurements of DEE and foraging activity of Arctic-dwelling Great Cormorants throughout the annual cycle. We demonstrate that, in fact, Great Cormorants have surprisingly low rates of DEE. This low DEE is attributed primarily to very low levels of foraging activity, particularly during winter, when the cormorants spent only 2% of their day submerged. Such a low level of fo...
Keywords: arctic, basal metabolic rate, catch per unit effort, cpue, daily energy expenditure, day length, diving depths, field metabolic rate, foraging efficiency, great cormorant, greenland, phalacrocorax carbo, seasonal variation,
Programme: 388
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. (2011). The relationship between sea surface temperature and population change of Great Cormorants Phalacrocorax carbo breeding near Disko Bay, Greenland
. Ibis (Lond. 1859), 153(1), 170–174.
Abstract: Arctic seas have warmed and sea ice has retreated. This has resulted in range contraction and population declines in some species, but it could potentially be a boon for others. Great Cormorants Phalacrocorax carbo have a partially wettable plumage and seem poorly suited to foraging in Arctic waters. We show that rates of population change of Cormorant colonies around Disko Bay, Greenland, are positively correlated with sea surface temperature, suggesting that they may benefit from a warming Arctic. However, although Cormorant populations may increase in response to Arctic warming, the extent of expansion of their winter range may ultimately be limited by other factors, such as sensory constraints on foraging behaviour during long Arctic nights.
Keywords: Arctic warming, climate change, diving, Phalacrocorax, thermoregulation, vision,
Programme: 388
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Picard G, Domine F, Krinner G, Arnaud L, Lefebvre E,. (2012). Inhibition of the positive snow-albedo feedback by precipitation in interior Antarctica. Bachelor's thesis, Nature Publishing Group, .
Keywords: limate change Cryospheric science
Programme: 1013
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. (2010). Candidate models for the IGRF 11th generation making use of extrapolated observatory data
. Earth Planets and Space, 62, 745–751.
Abstract: Three candidate models are produced in response to the call for IGRF-11 models. A main field model around epoch 2005.0 is based on one year of Oersted and CHAMP measurements, and is proposed for the definitive model for epoch 2005.0. A main field model around epoch 2009.5, based on two months of CHAMP measurements and extrapolated to 2010.0, is proposed as a main field model for epoch 2010.0. A secular variation model valid for 2010.0-2015.0, based on the extrapolation through exponential
smoothing of observatory monthly mean values, is proposed as a predictive secular variation model. Comparison of similar extrapolations made for previous IGRF generations with actual observations are presented and discussed.
Programme: 139;905
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. (2011). Continuous 25-yr aerosol records at coastal Antarctica I: inter-annual variability of ionic compounds and links to climate indices. Tellus B, .
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Jaffal A, Paris-Palacios S, Jolly S, Thailly A F, Delahaut L, Beall E, Roche H, Biagianti-Risbourg S, Betoulle S, . (2011). Cadmium and copper contents in a freshwater fish species (brook trout, Salvelinus fontinalis) from the subantarctic Kerguelen Islands
. Polar Biol., 34(3), 397–409.
Abstract: The subantarctic Kerguelen Islands (49 degrees S, 70 degrees E) contain freshwaters among the most isolated in the world from direct human activities. Cadmium and copper concentrations were analyzed in muscle and liver tissues of 57 non-migratory brook trout (Salvelinus fontinalis) inhabiting the Sud River of Kerguelen Islands. The mean cadmium concentration in liver was 1.13 mu g/g dry wt, within the range of levels measured in liver of marine fish from the Southern Ocean. Muscular Cd levels (0.12 mu g/g dry wt) were roughly ten times higher than those measured in Kerguelen's marine fish species. Copper levels were very high in the two organs (62.27 mu g/g dry wt in liver and 3.02 mu g/g dry wt in muscle) compared to those detected in fish from the Southern Ocean. Regarding the seasonal trend, the highest Cu and Cd muscular levels were measured in fish at the end of the austral winter, whereas the highest hepatic levels were observed at the end of the austral summer. Moreover, hepatic cadmium levels were higher in females than in males. These results could be related to brook trout spawning physiological preparations and foraging behavior during the summer period. We provide here the first results about Cu and Cd levels in liver and muscle of a freshwater fish species in an insular subantarctic context. They are in agreement with the high cadmium contamination found in fish of the Southern Ocean.
Programme: 409;1041
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. (2010). First Report of Nasturtium as a Natural Host of Cherry leaf roll virus on Amsterdam Island
. Plant Dis., 94, 477.
Abstract: Cherry leaf roll virus (CLRV) is a well-known virus belonging to the genus Nepovirus, but unlike most members of this genus, it is not known to be transmitted by nematodes but only through seeds and pollen. Since its first description in 1955 on Prunus avium L. in England (1), CLRV has been shown to have a worldwide distribution and a wide natural host range. During a survey of plant viruses in the French sub-Antarctic islands, samples from nasturtium plants (Tropaeolum majus), an introduced plant species, showing symptoms of leaf mosaic, deformation, and veinal necrosis were collected on Amsterdam Island. Upon mechanical transmission with sap extracts, necrotic ringspot and oak-leaf symptoms typical of Nepovirus infection were observed on the leaves of inoculated Nicotiana clevelandii and N. tabacum plants. Inoculation of healthy nasturtium plants resulted in mosaic and pin-point necrosis symptoms. Electron microscopy on negatively stained sap extracts revealed the presence of icosahedral virions, 28 to ...
Programme: 136
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