Abstract: Climate And Water Cycle Reconstruction Over The Last Centuries And Prediction Should Be Improved In The Southern Hemisphere (E.g. Last Ipcc Report). First, Direct Observations Are Scarce (E.g. In Antarctica, Mainly Basic Automatic Weather Station – Aws – Only Since The 50’s And Satellite Observations). As A Consequence, Climate And Water Cycle Reconstructions Are Largely Dependent On Proxy Measurements Such As Water Isotopes In Polar Ice Cores, Even Over The Last Century. Second, Climate And Water Cycle Reconstructions Using Models Should Be Improved. In Particular, Problems Have Been Identified For (1) Estimation Of Precipitation Amounts (Large Discrepancies Among Models Over The Austral Ocean And The Ice-sheet), (2) Description Of Particular Atmospheric Processes Associated With Cloud Microphysics And Exchanges Between Surface And Atmosphere In Polar Regions And (3) Seasonal To Interannual Evolution Of The Locations Of The Westerlies And Subtropical Jet And Associated Air Mass Trajectories. The Last Aspect Has Important Direct Consequences For The Atmospheric Dynamics In This Region But Also Indirect Consequences Such As The Links Between Westerlies, Co2 Outgassing And Sea Ice Extent In The Austral Ocean (Saunders Et Al. 2018; Menviel Et Al. 2018; Holland And Kwok, 2012). With The Objectives To Provide (1) A Better Description Of Water Cycle Dynamic In The Southern Ocean At Annual And Interannual Scales And (2) An Improved Transfer Function Between Climate / Water Cycle And Water Isotopes In This Region, A Bunch Of Instruments Measuring Continuously The Isotopic Composition Of Water In The Water Vapor And In The Precipitation Has Been Installed Over The Last Years Along A Transect From La Réunion To Antarctica.first Results From The Antarctic Instruments Reveal Clear Isotopic Signatures Of Large Scale Water Cycle Features Such As Atmospheric Rivers Dominating The Surface Mass Balance In Antarctica. In La Réunion, An Extensive Study Of The Drivers Of The Isotopic Composition Of The Water Vapor Showed That The Influence Of The Subtropical Westerly Jet Dominates The Water Isotopic Signal At Night. To Connect The Two Regions, An Instrument Is Running On Amsterdam Island Since November 2019 With First Results Showing A Clear Isotopic Signature During The High Pressure And Low Pressure Synoptic Events. Still, No In-depth Study Of The Data Trying To Connect The Isotopic Record In Amsterdam Island To Larger Scale Patterns Of The Water Cycle Has Been Initiated.the Goal Of This Internship Is To Provide The First Analyses Of The Isotopic (Water Vapor And Precipitation) Records On Amsterdam Island With A Comparison With Meteorological Data And Environmental Data Collected In Parallel On The Observatory Of Amsterdam Island (E.g. Gaseous Elemental Mercury). After These First Analyses Of The Data, Comparisons Will Be Performed With Water Isotopic Records In La Réunion Over Selected Events (Subtropical Jet Or Cold Fronts Intrusions). This Study Will Involve Analyses Of Meteorological Maps As Well As Backtrajectories.this Internship Requires Skills For (Python Or R Languages) And Involves Large Interactions Within A Large Research Team.

Abstract: Group-living is associated with both fitness benefits and costs for animals. In seabird colonies, spatial heterogeneity in social density and other environmental parameters may affect the quality of breeding territories. For instance, in king penguins, increased conspecific density has been correlated with increased stress hormone levels and increased energy expenditure in individual birds, suggesting a cost of colonial breeding. We unravelled the influences of early (genetic and early maternal effects) and rearing environments on chick growth trajectories, stress physiology and survival. Our results suggest that the rearing social environment (rather than biological background) can influence chicks’ phenotype, growth and survival. Especially, chicks reared in high density areas of the colony showed increased weight gain and survival probabilities. These results suggest either a difference in terms of parental quality between individual breeding at high and low social densities or a difference in chick’s competitiveness due to their early life social environment.

Abstract: Penguins are sea...birds. These highly evolved marine predators thrive in the oceanic habitat. Yet, they are conflicted – confronted to the duality of a life spent partly at sea, partly on-land. This life style has them subject to a number of very different ecological pressures. The ECONERGY polar project (IPEV #119) seeks to understand how king penguin cope with the constraints they face while living on-land, and the underlying physiological adaptations that allow them to do so. This includes studies dealing with fasting, parasites, predators, aggressive neighbors, climate and human disturbance. I will present some of the advances our project has made over the past decades, and where we will proceed in the years to come with a new project. We aim to understand bird stress from an integrative perspective, building a long-term observatory of penguin physiological responses to a changing world, and determining how breeding performances on land and foraging performances at sea are related.

Abstract: Animals from polar regions have evolved highly specialized adaptations to cope with cold climates, which put them at risk regarding the current rapid climate change. This is especially true for penguins who live most of the year in cold water, but breed on land in the spring/summer. Penguins are thereby likely to be threatened by periods of unusually warm temperatures on land. While heat stress is increasingly studied in warm regions, few studies have investigated whether heat stress could occur in polar regions, and to what extent it could affect individual health and reproduction. My aim is to fill this knowledge gap by leading a collaborative research project taking an integrative approach, from animal behavior to the sub-cellular level. This project aims at helping to better predict how penguin populations will respond to future climate change, and raise awareness of scientists, stakeholders and the general public towards an under-appreciated risk of climate change in polar regions.