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Boulinier, T., Betoulle, S., Caza, F., St Pierre, Y., Tornos, J., Gamble, A. &Amp; Tasiemski, A. (2020). Panorama des recherches et des derniers résultats sur les pathogènes en milieu polaire. Bachelor's thesis, , .
Abstract: Approches complémentaires des interactions hôte-parasite en zones polaire: de la détection de parasites et agents infectieux à l'étude fonctionnelle, écologique et évolutive de leurs interactions avec leurs hôtes.
Programme: 333,1151
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Agnieszka Beszczynska-Möller, Hanne Sagen, Peter Voss, Mikael K. Sejr, Thomas Soltwedel, Truls Johannessen, M.-N. Houssais, Andreas Rogge, Ian Allan, Frank Nilsen, Angelika Renner, L. H. Smedsrud, Nicholas Roden, Jean-Pierre Gattuso, Laurent Chauvaud, Claudie Marec, B. Cheng, Andrew King, Christine Provost, Marcel Babin, Mathilde Sorensen. (2020). Enhancement of ocean and sea ice in situ observations in the Arctic under the Horizon2020 project INTAROS.
Abstract: The H2020 project Integrated Arctic Observation System (INTAROS) aspires to increase the temporal and geographic coverage of in situ observations and add new key geophysical and biogeochemical variables in selected regions of the Arctic. By using a combination of mature and new instruments and sensors in integration with existing observatories, INTAROS aims to fill selected gaps in the present-day system and build additional capacity of the Arctic monitoring networks for ocean and sea ice. Three reference sites have been selected as key locations for monitoring ongoing Arctic changes: Costal Greenland, paramount for freshwater output from the Greenland ice sheet; North of Svalbard (covering the region from shelf to deep basin) – the hot-spot for ocean-air-sea ice interactions, and heat and biological energy input to the European Arctic; and Fram Strait – the critical gateway for exchanges between the Arctic and the World oceans. The existing observatories in the reference sites have been extended with new moorings and novel autonomous instrumentation, in particular for biogeochemical measurements and sea ice observations. Bottom-mounted instruments have been also implemented for seismic observations. A distributed observatory for ocean and sea ice in the Arctic Ocean and sub-Arctic seas includes non-stationary components such as ice-tethered observing platforms, float, gliders, and ships of opportunities, collecting multidisciplinary observations, still missing from the Arctic regions. New sensors, integrated platforms and experimental set-ups are currently under implementation during a two-year long deployment phase (2018-2020) with an aim to evaluate their sustained use in a future iAOS. New observations will be used for integration of new data products, demonstration studies and stakeholder consultations, contributing also to ongoing and future long-term initiatives (e.g. SAON).
Programme: 1141
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Vincent Lesur, Aude Chambodut. (2020). The French network of magnetic observatories.
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Razzolini Julia. (2020). Croissance musculaire chez le poussin de manchot royal, liens avec la saisonnalité et la condition corporelle. Bachelor's thesis, , .
Abstract: One of the fundamental principles of life history trait theory is the existence of trade-offs. The amount of energy available to living beings is a limited resource that must be shared among different biological functions. The combination of traits best suited to ecological constraints will be selected.
Growth is a crucial phase during which the future phenotype of the adult is established. This period between birth and the acquisition of independence from parents is characterized by very fast stature and weight growth and tissue maturation, particularly in bone and muscle. This phenomenon is marked by sustained parental nutrition. On an intraspecific scale, variations in individual chick growth may reflect the quality/experience of the parents. In some species, parental dietary intake may, regardless of quality, show wide seasonal fluctuations due to environmental changes and for developing individuals the quantity and quality of nutrients ingested and metabolized may be a limiting factor in growth. There is little information to understand the trade-offs in energy allocation that will be established to ensure survival and growth of the young in the case of inadequate dietary intakes.
The king penguin chick is an atypical animal model for the study of these strategies. This seabird has an unusually long one-year development cycle for a bird and its growth is interrupted by a period of severe food restriction during the 4 months of the southern winter. In addition, exceptionally with a penguin, the period of initiation of reproduction is asynchronous and extends over several months. A direct consequence is a shorter time of accumulation of energy reserves in late-born chicks. We aim to determine whether the particularly long cycle of this chick and the environmental constraints to which it is subjected result in particular adaptations in terms of the relative development of the two muscle belts, pelvic and pectoral, and whether this growth compromise is expressed in the same way in early and late born chicks.
Programme: 119
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Nicolas Crouzet, Abdelkrim Agabi, Tristan Guillot, Lyu Abe, François-Xavier Schmider, Djamel Mékarnia, Amaury H. M. J. Triaud, Yves Bresson, Nicolas Mauclert, Christophe Bailet, Dennis Breeveld, Sander Blommaert, Brian Shortt, Jean-Baptiste Daban, Anne-Marie Lagrange, Romain Touzé, Justin Dufour, Valentin Stee, Jocelyn Caruana. (2020). Towards ASTEP+, a two-color photometric telescope at Dome C, Antarctica (Vol. 11447).
Abstract: Dome C, Antarctica is unique in particular for long-duration astronomical observations due to the excellent weather conditions and nearly uninterrupted nights during the Southern winter period. The 40 cm telescope ASTEP has been operating successfully at the Concordia base, at Dome C, since 2010. We describe the new ASTEP+, a major upgrade of its camera box which will allow it to observe simultaneously in two colors. Approximately three times more photons will be collected for science, yielding more sensitive and accurate observations. The southern location of the telescope means that it is ideally located to follow-up exoplanetary targets in preparation for the future JWST and Ariel observations, in particular when located in the southern continuous viewing zones of these space-based telescopes.
Programme: 1066
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Olivier Gilg, Loïc Bollache, Eve Afonso, Glenn Yannic, Niels Martin Schmidt, Lars Holst Hansen, Jannik Hansen, Benoît Sittler, Johannes Lang, Nicolas Meyer, Brigitte Sabard, Vladimir Gilg, Anita Lang, Mathilde Lebbar, Voitto Haukisalmi, Heikki Henttonen, Jérôme Moreau. (2020). Are gastrointestinal parasites associated with the cyclic population dynamics of their arctic lemming hosts? (Vol. 10).
Abstract: Many rodents, including most populations of arctic lemmings (genus Dicrostonyx and Lemmus), have cyclic population dynamics. Among the numerous hypotheses which have been proposed and tested to explain this typical characteristic of some terrestrial vertebrate communities, trophic interactions have often been presented as the most likely drivers of these periodic fluctuations. The possible role of parasites has, however, only seldom been assessed. In this study, we genetically measured the prevalence of two endoparasite taxa, eimerians and cestodes, in 372 faecal samples from collared lemmings, over a five year period and across three distant sites in Northeast Greenland. Prevalence of cestodes was low (2.7% over all sites and years) and this taxon was only found at one site (although in 4 out of 5 years) in adult hosts. By contrast, we found high prevalence for eimerians (77.7% over all sites and years), which occurred at all sites, in every year, for both age classes (at the Hochstetter Forland site where both adult and juvenile faeces were collected) and regardless of reproductive and social status inferred from the characteristics of the lemming nests where the samples had been collected. Prevalence of eimerians significantly varied among years (not among sites) and was higher for juvenile than for adult lemmings at the Hochstetter Forland site. However, higher prevalence of eimerians (Pt) was only associated with lower lemming density (Nt) at one of the three sites and we found no delayed density dependence between Nt and Pt+1 to support the parasite hypothesis. Our results show that there is no clear relation between lemming density and eimerian faecal prevalence in Northeast Greenland and hence no evidence that eimerians could be driving the cyclic population dynamics of collared lemmings in this region.
Keywords: Cestodes Eimerians Faecal prevalence Greenland Population dynamics Rodent-parasites interactions
Programme: 1036
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Pierre Blévin, Scott A. Shaffer, Paco Bustamante, Frédéric Angelier, Baptiste Picard, Dorte Herzke, Børge Moe, Geir Wing Gabrielsen, Jan Ove Bustnes, Olivier Chastel. (2020). Contaminants, prolactin and parental care in an Arctic seabird: Contrasted associations of perfluoroalkyl substances and organochlorine compounds with egg-turning behavior (Vol. 291).
Abstract: Incubating eggs represents a trade-off for parent birds between spending enough time fasting to take care of the clutch and to get enough nutrients for self-maintenance. It is believed that the pituitary hormone prolactin plays an important role in such allocation processes. Incubation does not solely imply the active warming of the eggs but also the active egg-turning to facilitate absorption of albumen by the embryo, reduce malposition and prevent the embryo from adhering to the inner shell membrane. However, how prolactin secretion is related to egg-turning behaviors is presently poorly addressed. In addition, several environmental contaminants can affect parental care behaviors through their endocrine disrupting properties but the effects of such contaminants on egg-turning behaviors remain so far unexplored. Using artificial eggs equipped with miniaturized data loggers, we investigated the relationships between egg-turning behaviors, prolactin secretion and contaminants burden in Arctic black-legged kittiwakes (Rissa tridactyla). Specifically, we examined the relationships between blood concentrations of poly- and perfluoroalkyl substances (PFASs), organochlorines (OCs), mercury (Hg), plasma prolactin levels and both egg-turning frequency and angular change. We also incorporated baseline corticosterone levels since this glucocorticoid is known to affect parental care. Plasma prolactin levels were positively related to angular change in female kittiwakes while corticosterone was not related to egg-turning behaviors in either sex. Hg was not related to egg-turning behaviors in either sex. We found contrasting associations between OCs and PFASs, since polychlorinated biphenyls (PCBs) were negatively associated with angular change in females, contrary to linear perfluorooctanesulfonate (PFOSlin) and perfluoroalkyl carboxylic acids (PFCAs) which were positively related to egg-turning frequency and angular change in both sexes. Additionally, PFASs concentrations were positively related to prolactin levels in female kittiwake. The possible stimulation of prolactin secretion by PFASs could therefore make adult kittiwakes to allocate more time taking care of their eggs, and thus possibly modify the trade-off between spending enough time caring for the clutch and obtaining enough nutrients at sea.
Keywords: Black-legged kittiwake Corticosterone Egg-loggers Incubation behaviors Mercury Organochlorine compounds Perfluoroalkyl substances Prolactin
Programme: 330
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M. O. Naumenko-Dèzes, Y. Rolland, G. Lamarque, G. Duclaux, S. Gallet, J. Bascou, R. P. Ménot. (2020). Petrochronology of the Terre Adélie Craton (East Antarctica) evidences a long-lasting Proterozoic (1.7–1.5 Ga) tectono-metamorphic evolution — Insights for the connections with the Gawler Craton and Laurentia (Vol. 81).
Abstract: The Terre Adélie Craton displays superimposed strain fields related to the Neoarchean (2.6–2.4 Ga, M1) and Paleo-Mesoproterozoic (1.7–1.5 Ga, M2) metamorphic events. M1 is a regional granulite facies event, constrained by P-T modelling at ~0.8–1.0 GPa – 800–850 °C, followed by a decompressional retrogression in the upper amphibolite facies at ~0.6 GPa – 750 °C. M2 Stage 1 P-T peak is constrained at 0.6–0.7 GPa – 670–700 °C, followed by a steep P-T path down to 0.3 GPa – 550 °C. Retrogression after M2 PT peak occurred in a context of dextral shearing along the Mertz Shear Zone along with thrust motions within the eastern Terre Adélie Craton. In this paper, we present a series of 63 new 40Ar/39Ar ages of biotite and amphibole pairs in mafic rocks from a complete traverse of the Terre Adélie Craton. 40Ar/39Ar dating constrains M2 amphibolite facies metamorphism at a regional scale between 1700 and 1650 Ma, during stage 1 peak metamorphism. During retrogression, lower amphibolite facies recrystallization mainly occurred along vertical shear zones and mafic dykes between 1650 and 1600 Ma (Stage 2), followed by amphibolite to greenschist facies metamorphism until after 1500 Ma (Stage 3). At the scale of the Mawson continent, this event is related to the growth of an active margin above an oblique subduction zone. The supra-subduction model best explains opening of Dumont D'Urville and Hunter basins at 1.71 Ga followed by their rapid closure and metamorphism at 1.70 Ga. In this context, episodic shear zone reactivation and magmatic dyke emplacement led to a partial reequilibration of the 40Ar/39Ar system until <1500 Ma. This latter phase of mafic magmatism largely coincides with a hot spot event at the scale of the Gawler Craton and western Laurentia paleocontinent.
Keywords: Ar/Ar dating East Antarctica HT metamorphism Mafic magmatism P-T modelling Shear zones
Programme: 1003
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Vincent A. Viblanc, Quentin Schull, Antoine Stier, Laureline Durand, Emilie Lefol, Jean-Patrice Robin, Sandrine Zahn, Pierre Bize, François Criscuolo. (2020). Foster rather than biological parental telomere length predicts offspring survival and telomere length in king penguins.
Abstract: Because telomere length and dynamics relate to individual growth, reproductive investment and survival, telomeres have emerged as possible markers of individual quality. Here, we tested the hypothesis that, in species with parental care, parental telomere length can be a marker of parental quality that predicts offspring phenotype and survival. In king penguins (Aptenodytes patagonicus), we experimentally swapped the single egg of 66 breeding pairs just after egg laying to disentangle the contribution of prelaying parental quality (e.g., genetics, investment in the egg) and/or postlaying parental quality (e.g., incubation, postnatal feeding rate) on offspring growth, telomere length and survival. Parental quality was estimated through the joint effects of biological and foster parent telomere length on offspring traits, both soon after hatching (day 10) and at the end of the prewinter growth period (day 105). We expected that offspring traits would be mostly related to the telomere lengths (i.e., quality) of biological parents at day 10 and to the telomere lengths of foster parents at day 105. Results show that chick survival up to 10 days was negatively related to biological fathers’ telomere length, whereas survival up to 105 days was positively related to foster fathers’ telomere lengths. Chick growth was not related to either biological or foster parents’ telomere length. Chick telomere length was positively related to foster mothers’ telomere length at both 10 and 105 days. Overall, our study shows that, in a species with biparental care, parents’ telomere length is foremost a proxy of postlaying parental care quality, supporting the “telomere – parental quality hypothesis.”
Keywords: gene and early life environmental effects growth penguins reproduction investment telomere
Programme: 119
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Alice Carravieri, Paco Bustamante, Pierre Labadie, Hélène Budzinski, Olivier Chastel, Yves Cherel. (2020). Trace elements and persistent organic pollutants in chicks of 13 seabird species from Antarctica to the subtropics (Vol. 134). Bachelor's thesis, , .
Abstract: Seabirds from remote regions are mainly exposed to environmental contaminants from non-point contamination of their food webs. Pre-fledging seabird chicks are fed by their parents with marine prey captured in the vicinity of breeding colonies. Contaminant concentrations in tissues of pre-fledging chicks can thus be mostly related to local dietary sources, and have the potential to unravel spatial patterns of environmental contamination in marine ecosystems. Here, mercury (Hg), 13 other trace elements, and 18 persistent organic pollutants (POPs) were quantified in blood of chicks across four breeding locations that encompass a large latitudinal range in the southern Indian Ocean (from Antarctica, through subantarctic areas, to the subtropics), over a single breeding season. Thirteen species of penguins, albatrosses and petrels were studied, including endangered and near-threatened species, such as Amsterdam albatrosses and emperor penguins. Blood Hg burdens varied widely between species, with a factor of ~50 between the lowest and highest concentrations (mean ± SD, 0.05 ± 0.01 and 2.66 ± 0.81 µg g−1 dry weight, in thin-billed prions and Amsterdam albatrosses, respectively). Species relying on Antarctic waters for feeding had low Hg exposure. Concentrations of POPs were low in chicks, with the exception of hexachlorobenzene. Contaminant concentrations were mainly explained by species differences, but feeding habitat (inferred from δ13C values) and chicks’ body mass also contributed to explain variation. Collectively, our findings call for further toxicological investigations in Amsterdam albatrosses and small petrel species, because they were exposed to high and diverse sources of contaminants, and in macaroni penguins, which specifically showed very high selenium concentrations. Capsule Seabird chicks from four distant sites in the southern Indian Ocean had contrasted blood metallic and organic contaminant patterns depending on species, feeding habitat and body mass.
Keywords: Albatrosses; Mercury; Penguins; Petrels; Selenium; Stable isotopes
Programme: 109
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