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Iris-Amata Dion. (2015). Etude de la variabilité du mercure dans l’atmosphère de Dumont d'Urville,en Antarctique.
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Dommergue, A., Angot, H., and Magand, O. (2015). Recent measurements of atmospheric mercury in the Southern Hemisphere and their contribution to the understanding of Hg cycle.
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Angot, H., Dommergue, A., Magand, O., Helmig, D., Pirrone, N., and Sprovieri, F.:. (2015). Year-round record of gaseous mercury in air and snow: new insights into mercury reactivity in Central Antarctica (Dome C.
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Mieke Sterken, Elie Verleyen, Vivienne J. Jones, Dominic A. Hodgson, Wim Vyverman, Koen Sabbe, Bart Van de Vijver. (2015). An illustrated and annotated checklist of freshwater diatoms (Bacillariophyta) from Livingston, Signy and Beak Island (Maritime Antarctic Region) (Vol. 148).
Abstract: Background and aims – Non-marine diatom communities in the Antarctic Region are characterized by a typical species composition, dominated by a large number of Antarctic endemic species. Despite recent advances in our knowledge about the diversity and biogeography of non-marine Antarctic diatoms, the flora of many Antarctic localities is still only poorly known, which can result in incorrect conceptions of species' distributions. The present paper provides a taxonomically consistent illustrated checklist of the diatom flora observed in recent and (sub)fossil non-marine sediments of three islands in the proximity of the northern Antarctic Peninsula, namely; Signy Island (South Orkneys), Livingston Island (South Shetlands) and Beak Island (James Ross Island group). Methods – The diatom flora of 66 samples collected from a wide variety of lakes and localities on the three above-mentioned islands has been studied using light and scanning electron microscopy. The biogeographical distribution of the composing taxa has been assessed on the basis of quality-checked distribution data from the recent literature. Key results – One hundred and two diatom taxa, belonging to thirty-four genera, were observed. Pinnularia (twelve taxa), Chamaepinnularia, Luticola, Planothidium, Psammothidium and Stauroneis (seven taxa each), Nitzschia (six taxa), Humidophila and Navicula (five taxa each) proved to be the most species-rich genera. Original morphometric data (including length, width and stria density) and illustrations are presented for all taxa observed. Forty-one species are hitherto only known from the Antarctic region. The exact taxonomic identity of twenty species remains uncertain and requires further study. It is suspected that many of these will also turn out to be restricted to the Antarctic region, suggesting that about half of all taxa observed are probably endemic to the Antarctic. Conclusions – The diatom flora of the three investigated localities comprises a large proportion of typical Antarctic taxa, many of which have only recently been split off from their presumably cosmopolitan relatives.
Programme: 1133
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Reichert S, Rojas E R, Zahn S, Robin J-P, Criscuolo F, Massemin S, . (2015). Maternal telomere length inheritance in the king penguin
. HEREDITY, 114(1), 10–16.
Abstract: Telomeres are emerging as a biomarker for ageing and survival, and are likely important in shaping life-history trade-offs. In particular, telomere length with which one starts in life has been linked to lifelong survival, suggesting that early telomere dynamics are somehow related to life-history trajectories. This result highlights the importance of determining the extent to which telomere length is inherited, as a crucial factor determining early life telomere length. Given the scarcity of species for which telomere length inheritance has been studied, it is pressing to assess the generality of telomere length inheritance patterns. Further, information on how this pattern changes over the course of growth in individuals living under natural conditions should provide some insight on the extent to which environmental constraints also shape telomere dynamics. To fill this gap partly, we followed telomere inheritance in a population of king penguins (Aptenodytes patagonicus). We tested for paternal and maternal influence on chick initial telomere length (10 days old after hatching), and how these relationships changed with chick age (at 70, 200 and 300 days old). Based on a correlative approach, offspring telomere length was positively associated with maternal telomere length early in life (at 10 days old). However, this relationship was not significant at older ages. These data suggest that telomere length in birds is maternally inherited. Nonetheless, the influence of environmental conditions during growth remained an important factor shaping telomere length, as the maternal link disappeared with chicks/' age.
Programme: 119
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Jenouvrier Stephanie, Holland Marika, Stroeve Julienne, Serreze Mark, Barbraud Christophe, Weimerskirch Henri, Caswell Hal, . (2014). Projected continent-wide declines of the emperor penguin under climate change
. Nature Climate Change, 4(8), 715–718.
Abstract: Climate change has been projected to affect species distribution1 and future trends of local populations2, 3, but projections of global population trends are rare. We analyse global population trends of the emperor penguin (Aptenodytes forsteri), an iconic Antarctic top predator, under the influence of sea ice conditions projected by coupled climate models assessed in the Intergovernmental Panel on Climate Change (IPCC) effort4. We project the dynamics of all 45 known emperor penguin colonies5 by forcing a sea-ice-dependent demographic model6, 7 with local, colony-specific, sea ice conditions projected through to the end of the twenty-first century. Dynamics differ among colonies, but by 2100 all populations are projected to be declining. At least two-thirds are projected to have declined by >50% from their current size. The global population is projected to have declined by at least 19%. Because criteria to classify species by their extinction risk are based on the global population dynamics8, global analyses are critical for conservation9. We discuss uncertainties arising in such global projections and the problems of defining conservation criteria for species endangered by future climate change.
Programme: 109
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Garcin N, Viblanc VA, Schull Q, Michaux D, Reichert S, Robin JP, Bize P, Stier A. (2021). Naturally equipped to resist stress.
Abstract: Stress exposure and stress response are likely to vary according to life history strategies and environmental contexts. Although the acute release of glucocorticoids in response to unpredictable environmental conditions may lead to adaptative behavioral and physiological responses, exposure to high glucocorticoid levels on the long-term usually leads to deleterious cascading effects on animal’s physiology, behavior and fitness. Yet, some species may be more adapted to cope with challenging events than others and might naturally possess protective mechanisms limiting the adverse consequences of prolonged exposure to high glucocorticoid levels. King penguin chicks being naturally exposed to harsh weather, prolonged fasting and constant predation pressure, we investigated the life-history, behavioral and physiological consequences of an experimental increase in corticosterone levels on the medium and long-term (after removing implants), predicting to find relatively few costs associated with such treatment. Although non-significant, CORT-treated chicks were slightly larger, fledged slightly earlier and had slightly higher survival chances than placebo chicks. CORT-treated chicks were significantly more aggressive and displayed lower corticosterone response to acute stress on the medium term, while their physical activity and whole-body energetics were not significantly affected. While mitochondrial density was not significantly affected by the CORT treatment, CORT-treated chicks had lower oxidative stress levels on the long-term than placebo ones, and no significant impact was observed on telomere shortening. Finally, the expression of several genes (i.e. CORT receptor, HSP90, mTOR, NRF2 and TERF2) was up regulated in treated chicks, which could potentially mediate the apparent ‘stress’ resistance we observed at the phenotypic level.
Programme: 119
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Labonne J., Robin J.-p., Améziane N., Barbraud C., Bétoulle S., Bost C., Boulinier T., Charassin J.-b., Cotté C., Eleaume M., Gallut C., Gaudin P., Guinet C., Hennion F., Koubbi P., Le Bohec C., Lebouvier M., Mazé C., Renault D., Ropert-coudert Y., Saucède T. Et Weimerskirch H. (2020). Implementation of the Long Term Ecological Research network of the French Southern and Antarctic Lands (LTER ZATA “ Zone Atelier Antarctique et Terres Australes”): toward an overall monitoring of the southern ecosystem through its marine and terrestrial communities.
Abstract: Since 2000, the French Long Term Ecological Research network of the French Southern and Antarctic Lands (LTER ZATA “ Zone Atelier Antarctique et Terres Australes”) has endeavoured to monitor the dynamics of biodiversity in Antarctic and sub-Antarctic marine and terrestrial ecosystems. Our LTER encompasses multiple scientific programs and can provide access to long term monitoring of more than 40 marine, freshwater and terrestrial vertebrate species (including 27 bird species), 20 terrestrial and freshwater plant and invertebrate species. For some species, monitoring was initiated well before the 2000s, as earlier as the years 1960-1970. More recently, monitorings have been initiated at the community level for pelagic and coastal marine biota, and were complemented by eco-physiological, eco-epidemiological and stress observing projects focussing on multiple species and communities. The main objective of our LTER is to provide a general dashboard to assess health of southern ecosystems along with the selective pressures and overall resilience due to environmental changes. The French LTER ZATA has strongly benefited from sustained support from the French Polar Institute over decades, clearly linking fundings and resource allocations to our capacity to assess and understand southern ecosystems. In this talk, we will give a first picture of this dashboard based on our existing databases. We will also present future developments and strategies that, for sure, have now to be integrated at the international level.
Programme: 119
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Karine Delord, Christophe Barbraud, David Pinaud, Stephanie Ruault, Samantha C. Patrick, Henri Weimerskirch. (2019). Individual consistency in the non-breeding behavior of a long-distance migrant seabird, the Grey Petrel Procellaria cinerea (Vol. 47).
Abstract: There is growing interest in the consistency of individual differences in animal behavior as it relates to life history traits and fitness. Despite the relatively large number of studies investigating repeatable behaviors, studies have only recently investigated repeatability in foraging or migratory behaviors, and this has seldom been explored between years. We examined the individual consistency in foraging behavior of the Grey Petrel Procellaria cinerea, a pelagic long-distance migrant seabird. We analyzed how foraging, activity, and migratory patterns were repeatable across different seasons. We used tracking data to monitor the migratory movements and behavior of individuals during the non-breeding period over five years. Despite the small sample size, we found that there was a relatively high individual consistency in wintering strategies across years, with birds displaying high fidelity to their non-breeding destinations during consecutive years. Activity parameters, date of departure of inward migration, duration of migration, and duration spent in non-breeding areas were repeatable as well. The duration of the non-breeding period was the most repeatable, reflecting consistent departure times and, to a lesser extent, consistent arrival times. A high overall repeatability was seen in the timing of return migration. With respect to sex, males tended to be more consistent in their migration strategy (i.e., timing of migration, time spent in non-breeding areas) than females. Although conditions during the Holocene have generally been stable in the Southern Ocean, species lacking variability in migratory traits are probably at a considerable disadvantage in terms of their capacity to respond to the rapid environmental changes currently underway.
Programme: 109
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Marion Leduc-Leballeur, Ghislain Picard, Giovanni Macelloni, Arnaud Mialon, Yann H. Kerr. (2020). Melt in Antarctica derived from Soil Moisture and Ocean Salinity (SMOS) observations at L band (Vol. 14).
Abstract: Melt occurrence in Antarctica is derived from L-band observations from the Soil Moisture and Ocean Salinity (SMOS) satellite between the austral summer 2010–2011 and 2017–2018. The detection algorithm is adapted from a threshold method previously developed for 19 GHz passive microwave measurements from the special sensor microwave imager (SSM/I) and special sensor microwave imager sounder (SSMIS). The comparison of daily melt occurrence retrieved from 1.4 and 19 GHz observations shows an overall close agreement, but a lag of few days is usually observed by SMOS at the beginning of the melt season. To understand the difference, a theoretical analysis is performed using a microwave emission radiative transfer model. It shows that the sensitivity of 1.4 GHz signal to liquid water is significantly weaker than at 19 GHz if the water is only present in the uppermost tens of centimetres of the snowpack. Conversely, 1.4 GHz measurements are sensitive to water when spread over at least 1 m and when present in depths up to hundreds of metres. This is explained by the large penetration depth in dry snow and by the long wavelength (21 cm). We conclude that SMOS and higher-frequency radiometers provide interesting complementary information on melt occurrence and on the location of the water in the snowpack.
Programme: 1110
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