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
|
David Renault. (2020). A Review of the Phenotypic Traits Associated with Insect Dispersal Polymorphism, and Experimental Designs for Sorting out Resident and Disperser Phenotypes (Vol. 11). Bachelor's thesis, , .
Abstract: Dispersal represents a key life-history trait with several implications for the fitness of organisms, population dynamics and resilience, local adaptation, meta-population dynamics, range shifting, and biological invasions. Plastic and evolutionary changes of dispersal traits have been intensively studied over the past decades in entomology, in particular in wing-dimorphic insects for which literature reviews are available. Importantly, dispersal polymorphism also exists in wing-monomorphic and wingless insects, and except for butterflies, fewer syntheses are available. In this perspective, by integrating the very latest research in the fast moving field of insect dispersal ecology, this review article provides an overview of our current knowledge of dispersal polymorphism in insects. In a first part, some of the most often used experimental methodologies for the separation of dispersers and residents in wing-monomorphic and wingless insects are presented. Then, the existing knowledge on the morphological and life-history trait differences between resident and disperser phenotypes is synthetized. In a last part, the effects of range expansion on dispersal traits and performance is examined, in particular for insects from range edges and invasion fronts. Finally, some research perspectives are proposed in the last part of the review.
Keywords: fecundity hostile matrix life-history mating morphology movement range expansion reproduction wing-dimorphic wing-monomorphic
Programme: 136
|
Detlev Helmig, Daniel Liptzin, Jacques Hueber, Joel Savarino. (2020). Impact of exhaust emissions on chemical snowpack composition at Concordia Station, Antarctica (Vol. 14). Bachelor's thesis, , .
Abstract: The chemistry of reactive gases inside the snowpack and in the lower atmosphere was investigated at Concordia Station (Dome C), Antarctica, from December 2012 to January 2014. Measured species included ozone, nitrogen oxides, gaseous elemental mercury (GEM), and formaldehyde, for study of photochemical reactions, surface exchange, and the seasonal cycles and atmospheric chemistry of these gases. The experiment was installed ≈1 km from the station main infrastructure inside the station clean air sector and within the station electrical power grid boundary. Ambient air was sampled continuously from inlets mounted above the surface on a 10 m meteorological tower. In addition, snowpack air was collected at 30 cm intervals to 1.2 m depth from two manifolds that had both above- and below-surface sampling inlets. Despite being in the clean air sector, over the course of the 1.2-year study, we observed on the order of 50 occasions when exhaust plumes from the camp, most notably from the power generation system, were transported to the study site. Continuous monitoring of nitrogen oxides (NOx) provided a measurement of a chemical tracer for exhaust plumes. Highly elevated levels of NOx (up to 1000 × background) and lowered ozone (down to ≈50 %), most likely from reaction of ozone with nitric oxide, were measured in air from above and within the snowpack. Within 5–15 min from observing elevated pollutant levels above the snow, rapidly increasing and long-lasting concentration enhancements were measured in snowpack air. While pollution events typically lasted only a few minutes to an hour above the snow surface, elevated NOx levels were observed in the snowpack lasting from a few days to ≈ 1 week. GEM and formaldehyde measurements were less sensitive and covered a shorter measurement period; neither of these species' data showed noticeable concentration changes during these events that were above the normal variability seen in the data. Nonetheless, the clarity of the NOx and ozone observations adds important new insight into the discussion of if and how snow photochemical experiments within reach of the power grid of polar research sites are possibly compromised by the snowpack being chemically influenced (contaminated) by gaseous and particulate emissions from the research camp activities. This question is critical for evaluating if snowpack trace chemical measurements from within the camp boundaries are representative for the vast polar ice sheets.
Programme: 1177
|
|
Albane Barbero, Camille Blouzon, Joël Savarino, Nicolas Caillon, Aurélien Dommergue, Roberto Grilli. (2020). A compact incoherent broadband cavity-enhanced absorption spectrometer for trace detection of nitrogen oxides, iodine oxide and glyoxal at levels below parts per billion for field applications (Vol. 13). Bachelor's thesis, , .
|
Rémi Bigonneau, Romain Bazire, Cédric Marteau, Christophe Barbraud, Joan Ferrer-Obiol, Karine Delord. (2020). First record of Black-winged Pratincole Glareola nordmanni for Amsterdam Island, Indian Ocean (Vol. 27). Bachelor's thesis, , .
Abstract: Première mention de la Glaréole à ailes noires Glareola nordmanni pour l’Île Amsterdam, Océan Indien. Une Glaréole à ailes noires Glareola nordmanni de premier hiver à été observée sur l’Île Amsterdam, dans le sud de l’Océan indien, les 12–16 novembre 2013. Il s’agît de la première donnée de cette espèce paléarctique pour l’île. Les mentions antérieures les plus proches proviennent de l’île d’Alphonse, aux Seychelles, à environ 4.200 km de l’Île Amsterdam.
Programme: 109
|
L. G. Bouma, J. D. Hartman, R. Brahm, P. Evans, K. A. Collins, G. Zhou, P. Sarkis, S. N. Quinn, J. de Leon, J. Livingston, C. Bergmann, K. G. Stassun, W. Bhatti, J. N. Winn, G. Á Bakos, L. Abe, N. Crouzet, G. Dransfield, T. Guillot, W. Marie-Sainte, D. Mékarnia, A. H. M. J. Triaud, C. G. Tinney, T. Henning, N. Espinoza, A. Jordán, M. Barbieri, S. Nandakumar, T. Trifonov, J. I. Vines, M. Vuckovic, C. Ziegler, N. Law, A. W. Mann, G. R. Ricker, R. Vanderspek, S. Seager, J. M. Jenkins, C. J. Burke, D. Dragomir, A. M. Levine, E. V. Quintana, J. E. Rodriguez, J. C. Smith, B. Wohler. (2020). Cluster Difference Imaging Photometric Survey. II. TOI 837: A Young Validated Planet in IC 2602 (Vol. 160). Bachelor's thesis, , .
Abstract: We report the discovery of TOI 837b and its validation as a transiting planet. We characterize the system using data from the NASA TESS mission, the ESA Gaia mission, ground-based photometry from El Sauce and ASTEP400, and spectroscopy from CHIRON, FEROS, and Veloce. We find that TOI 837 is a $T=9.9$ mag G0/F9 dwarf in the southern open cluster IC 2602. The star and planet are therefore $35^{+11}{-5}$ million years old. Combining the transit photometry with a prior on the stellar parameters derived from the cluster color-magnitude diagram, we find that the planet has an orbital period of $8.3\,{\rm d}$ and is slightly smaller than Jupiter ($R{\rm p} = 0.77^{+0.09}{-0.07} \,R{\rm Jup}$). From radial velocity monitoring, we limit $M{\rm p}\sin i$ to less than 1.20 $M{\rm Jup}$ (3-$\sigma$). The transits either graze or nearly graze the stellar limb. Grazing transits are a cause for concern, as they are often indicative of astrophysical false positive scenarios. Our follow-up data show that such scenarios are unlikely. Our combined multi-color photometry, high-resolution imaging, and radial velocities rule out hierarchical eclipsing binary scenarios. Background eclipsing binary scenarios, though limited by speckle imaging, remain a 0.2% possibility. TOI 837b is therefore a validated adolescent exoplanet. The planetary nature of the system can be confirmed or refuted through observations of the stellar obliquity and the planetary mass. Such observations may also improve our understanding of how the physical and orbital properties of exoplanets change in time.
Keywords: Astrophysics – Earth and Planetary Astrophysics Astrophysics – Solar and Stellar Astrophysics
Programme: 1066
|
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
|
Christophe Barbraud, Karine Delord, Charles A. Bost, Adrien Chaigne, Cédric Marteau, Henri Weimerskirch. (2020). Population trends of penguins in the French Southern Territories (Vol. 43). Bachelor's thesis, , .
Abstract: Penguins are important top consumers in marine food webs and are one of the most threatened bird families, especially by climate change and food web alterations by marine fisheries. Yet, long-term population trends are lacking or are uncertain for many populations. Seven species of penguins breeding at the French Southern Territories in the southern Indian Ocean on the Crozet, Kerguelen, Saint-Paul–Amsterdam archipelagos and in Terre Adélie/Adelie Land, Antarctica are monitored regularly. This monitoring started in the early 1950s and most populations have been surveyed during the past four years, allowing assessments of population trends. King penguins increased at nearly all breeding sites within the Crozet and Kerguelen archipelagos. Emperor penguins have decreased at Terre Adélie/Adelie Land, with a partial recovery of the colony during the 2010s. Gentoo penguin populations at Crozet and Kerguelen are highly variable but stable. Adélie penguins have been increasing in Terre Adélie/Adelie Land. The trends in eastern rockhopper penguins vary between colonies and archipelagos. Northern rockhopper penguins have continuously decreased in numbers at Amsterdam Island, but appear to have increased at the nearby Saint-Paul Island. Macaroni penguins have first increased and then stabilized since the 2000s at Kerguelen and are stable at the Crozet Islands. Overall, most penguin populations breeding in the French Southern Territories increased or were stable over the past 30–60 years, with the exception of the northern rockhopper penguin, king and gentoo penguins on Crozet and the emperor penguin. The ecological reasons for these trends are poorly understood and require further investigation.
Programme: 109,394
|
|
L. Edel, C. Claud, C. Genthon, C. Palerme, N. Wood, T. L’Ecuyer, D. Bromwich. (2020). Arctic Snowfall from CloudSat Observations and Reanalyses (Vol. 33). Bachelor's thesis, , .
|
Aymeric. Fromant, C. M. Miskelly, J. P. Y. Arnould, C.-A. Bost. (2020). Artificial burrows as a tool for long-term studies of diving petrels (Vol. 43). Bachelor's thesis, , .
Abstract: Long-term studies are essential to determine demographic parameters and population trends in seabirds. However, studies to date have focused mainly on the larger and accessible species. While small seabirds (< 200 g) play a major role in marine ecosystems, their nesting habitat, which is typically fragile convoluted burrows, largely preclude long-term surveys. This study evaluated the installation of artificial burrows as a tool to facilitate ongoing long-term research on small burrowing seabirds. We tested the use and acceptance of artificial burrows during the chick-rearing period of common diving petrels (Pelecanoides urinatrix) on Mayes Island, Kerguelen Archipelago, southern Indian Ocean. The growth rate, mass at fledging and fledging rate of chicks were similar between artificial and natural burrows. Similarly, there was no difference in occupancy rate 1 and 2 years after artificial burrows were installed. The installation of artificial burrows during the chick-rearing period of a small burrowing seabird appears to be an effective way to facilitate ongoing monitoring and research and, therefore, we recommend the wider use of artificial burrows to facilitate monitoring and research of other small burrow-nesting procellariiform species.
Programme: 109,394
|
