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Jérémy Tornos. (2021). Approches intégrées en écologie de la conservation des oiseaux marins : cas de l’utilisation d'autovaccins pour la conservation des albatros sur l'île d'Amsterdam.
Abstract: L’Albatros à nez jaune de l’océan indien (Thalassarche carteri) est une espèce menacée d’extinction dont la population principale, qui se reproduit sur l’île Amsterdam (Terres Australes et Antarctiques Françaises), connait un déclin et une très forte mortalité des jeunes individus depuis plusieurs décennies. La bactérie responsable du choléra aviaire, Pasteurella multocida, est suspectée comme étant à l'origine de ces mortalités et notre équipe évalue depuis plusieurs années maintenant l'utilisation d'un vaccin pour protéger les poussins, via leur vaccination directe, mais aussi celle des femelles reproductrices susceptibles de transmettre des anticorps protecteurs à leur poussin. Le vaccin utilisé est un vaccin autologue (autovaccin) spécifiquement développé par Ceva-Biovac contre une souche de la bactérie Pasteurella multocida isolée sur cadavre d’albatros. Suite à l’obtention de premiers résultats prometteurs, les objectifs de la thèse étaient d’ajuster le protocole de vaccination, mais également de mieux appréhender et décrire les processus éco-épidémiologiques en jeu au sein des populations de vertébrés de l’île Amsterdam. Ceci a reposé sur l'analyse fine du suivi de couples reproducteurs année après année, mais aussi sur l'utilisation de données éco-épidémiologiques expérimentales complémentaires, notamment une nouvelle formulation du vaccin. Une diversité de pathogènes responsables de mortalités a pu être caractérisée. L’âge optimal de vaccination des poussins parait être vers 10 jours et la vaccination des femelles reproductrices semble pouvoir protéger les poussins pendant plusieurs années, mais la forte densité de rats (Rattus norvegicus) actifs dans les colonies a rendu difficile l’identification d’un effet protecteur fort du vaccin. Les résultats obtenus améliorent la compréhension des mécanismes de circulation d'agents infectieux chez des espèces à reproduction coloniale et permettront de comparer les bénéfices relatifs attendus de différents scénarios de vaccination. Le travail montre l’importance d’intégrer des approches complémentaires, notamment du domaine biomédical et de l’écologie des populations, pour aborder la problématique de l’émergence de maladies infectieuses dans le contexte des changements environnementaux actuels.
Programme: 1151
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Andrés Barbosa, Arvind Varsani, Virginia Morandini, Wray Grimaldi, Ralph E. T. Vanstreels, Julia I. Diaz, Thierry Boulinier, Meagan Dewar, Daniel González-Acuña, Rachael Gray, Clive R. McMahon, Gary Miller, Michelle Power, Amandine Gamble, Michelle Wille. (2021). Risk assessment of SARS-CoV-2 in Antarctic wildlife (Vol. 755).
Abstract: The coronavirus disease 2019 (COVID-19) pandemic is caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). This pathogen has spread rapidly across the world, causing high numbers of deaths and significant social and economic impacts. SARS-CoV-2 is a novel coronavirus with a suggested zoonotic origin with the potential for cross-species transmission among animals. Antarctica can be considered the only continent free of SARS-CoV-2. Therefore, concerns have been expressed regarding the potential human introduction of this virus to the continent through the activities of research or tourism to minimise the effects on human health, and the potential for virus transmission to Antarctic wildlife. We assess the reverse-zoonotic transmission risk to Antarctic wildlife by considering the available information on host susceptibility, dynamics of the infection in humans, and contact interactions between humans and Antarctic wildlife. The environmental conditions in Antarctica seem to be favourable for the virus stability. Indoor spaces such as those at research stations, research vessels or tourist cruise ships could allow for more transmission among humans and depending on their movements between different locations the virus could be spread across the continent. Among Antarctic wildlife previous in silico analyses suggested that cetaceans are at greater risk of infection whereas seals and birds appear to be at a low infection risk. However, caution needed until further research is carried out and consequently, the precautionary principle should be applied. Field researchers handling animals are identified as the human group posing the highest risk of transmission to animals while tourists and other personnel pose a significant risk only when in close proximity (< 5 m) to Antarctic fauna. We highlight measures to reduce the risk as well as identify of knowledge gaps related to this issue.
Keywords: Antarctica Coronavirus COVID-19 Mitigation measures Reverse zoonoses Transmission
Programme: 1151
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Armelle Decaulne, Najat Bhiry, Janie Faucher-Roy, Clara Pelletier Boily. (2021). The development of Kangiqsualujjuaq and the threat of snow avalanches in a permafrost degradation context, Nunavik, Canada.
Abstract: Slope processes are active in the rolling plateau landscapes of Nunavik, Northern Québec, Canada. There are a few short but very steep escarpments in this region. On January 1st, 1999 a powerful snow avalanche struck Kangiqsualujjuaq, one of the 14 Inuit villages in Nunavik. Nine people died and 25 were injured. This village and its surrounding are located within a glacial valley, in a periglacial environment. There is significant population growth, as well as in the other villages in Nunavik. As early as 1999-2000, there was a significant spatial reorganization of the village's infrastructures to avoid the impact of other snow-avalanche events. The main objective of this paper is to examine the village expansion in response to snow-avalanche process and population growth, within an area constrained with permafrost thawing and steep slopes. From naturalist geomorphologic methods, written sources such as archive documents and aerial photographs, the results show that slopes above Kangiqsualujjuaq are prone to release snow avalanches during blizzards from uncommon directions, and that the newly built housing may be at risk in some places, due to the conjunction of snow avalanches and permafrost thawing.
Keywords: active layer Canada demographic growth Nordic village slopes snow avalanches
Programme: 1148
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Samuel Veilleux, Armelle Decaulne, Najat Bhiry. (2021). Snow cornice and snow avalanche monitoring using automatic time lapse cameras in Tasiapik Valley, Nunavik (Québec) during the winter of 2017–2018 (Vol. 7).
Abstract: A series of automatic time-lapse cameras installed along the southwestern side of Tasiapik Valley, near the village of Umiujaq, Nunavik (northern Québec) documented several departure modes and types of snow involved in snow avalanches during winter 2017–2018. These included cornice–avalanche dynamics, slab and loose snow avalanches, and clean and dirty snow avalanches. At the top of the selected slope, a camera monitored the development of a snow cornice beginning in November 2017, detecting multiple cornice failures over the winter and spring. The track and deposition area of the runout paths were monitored from two cameras downslope, revealing the concomitance of snow–cornice fall and snow avalanche triggering. Snow avalanche activity remained relatively infrequent until the end of May 2018. Spring snow avalanche activity is characterized by wet and dirty snow avalanches carrying debris to the foot of the slope and by runout zones located near the road along the slope.
Programme: 1148
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Armelle Decaulne, Najat Bhiry, Fabienne Joliet, Laine Chanteloup, Thora Martina Herrmann, Bruno Persat, Daniel Germain, Orsane Rousset. (2021). TAKUJUQ: Where Art and Science meet in Nunavik.
Abstract: The TUKISIK (Tukisigasuaqatigit: Understanding together) is a scientific program, ongoing since 2014, concerning human-environment interactions, reinforcing links between scientists and several communities.
Programme: 1148
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Alexandra Lavrillier, Semen Gabyshev, Liudmila Egorova, Galina Makarova, Maia Lomovtseva-Adukanova. (2021). Analysing Non-Existent and Existing Tourisms in Eastern Siberia among the Evenki, Even, Koryak and Itelmen.
Abstract: Depuis l'effondrement de l'Union soviétique, les villageois et les nomades autochtones sibériens ont souvent eu du mal à subvenir à leurs besoins. Certains natifs pensent que l'ethno-tourisme peut être une source de revenus, mais il y a actuellement peu de tourisme en Sibérie. Dans l'Arctique circumpolaire, le tourisme est présenté comme une source de croissance économique. Le Plan Officiel de Développement Economique de la Fédération de Russie à l'Horizon 2030 vise également le développement du tourisme et, à cette fin, la Russie mobilise des équipes spécialisées. Quelles seront les conséquences économiques, sociales et culturelles pour les communautés autochtones? Quelles formes de tourisme leur seraient bénéfiques ? Quelles perceptions les autochtones de Sibérie ont-ils du tourisme ?Cet article transdisciplinaire compare le tourisme inexistant, tel qu'il est imaginé, souhaité ou déploré par les citadins, les villageois, les éleveurs nomades autochtones de la République Sakha-Yakoutie et de la région de l'Amour, avec diverses expériences d’ethno-tourisme existants au Kamtchatka. Basé sur des données ethnographiques recueillies entre 1994 et 2016, l'article a utilisé les méthodes de terrains participatifs et de l’anthropologie classique, et des mises en hypothèses effectuées par des co-chercheurs autochtones et un anthropologue. Il analyse les aspects économiques, sociaux, culturels et administratifs des tourismes existants et non existants.
Keywords: changement culturel communautés autochtones economies Even Evenk invention de la tradition Itelmen Koriak nomades Russie Sibérie Tourisme
Programme: 1127
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Alexandra Lavrillier, Semen Gabyshev. (2021). An Indigenous science of the climate change impacts on landscape topography in Siberia (Vol. 50).
Abstract: As with many Indigenous Peoples, the Siberian Evenki nomadic reindeer herders and hunters have observed increasing consequences of climate change on the cryosphere and biodiversity. Since 2017, they have observed previously unthinkable changes in topography. Based exclusively on an Evenki Indigenous Ecological Knowledge system-social anthropology coproduction and community-based continuous observation from 2013, this paper analyses what a Subarctic People observes, knows, does not know, hypothesizes, and models (collectively or individually) about climate change impacts on Indigenous landscape types typical for local river systems. These landscapes are crucial tools for traditional activities. To the nomads, the landscape changes emerge from general anomalies: competition from new plant species; atmosphere–ground–vegetation interactions; icing blisters decrease; rising receding river water interactions; the formation of new soil, ice, and snow types; increasing ground, air, and water temperatures; and the (non)circulation of harsh air throughout the snowpack. We demonstrate the science-like structure and value of Indigenous typologies and hypotheses.
Programme: 1127
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Lavrillier, A., Gabyshev S. (2021). A Siberian Indigenous Knowledge System for Understanding Climate Change (Vol. II).
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Lavrillier A. (2021). Le pas léger sur la Terre des peuples des neiges (Vol. Hors-Série).
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Dedieu, J.-P., A. Wendleder, B. Cerino, J. Boike, E. Bernard, J.-C. Gallet, and H.-W. Jacobi. (2021). Snow change detection from polarimetric SAR time-series at X-band (Svalbard, Norway), EGU General Assembly 2021, online, 19–30 Apr 2021, EGU21-149..
Abstract: Due to recent climate change conditions, i.e. increasing temperatures and changing precipitation patterns, arctic snow cover dynamics exhibit strong changes in terms of extent and duration. Arctic amplification processes and impacts are well documented expected to strengthen in coming decades. In this context, innovative observation methods are helpful for a better comprehension of the spatial variability of snow properties relevant for climate research and hydrological applications. Microwave remote sensing provides exceptional spatial and temporal performance in terms of all-weather application and target penetration. Time-series of Synthetic Active Radar images (SAR) are becoming more accessible at different frequencies and polarimetry has demonstrated a significant advantage for detecting changes in different media. Concerning arctic snow monitoring, SAR sensors can offer continuous time-series during the polar night and with cloud cover, providing a consequent advantage in regard of optical sensors. The aim of this study is dedicated to the spatial/temporal variability of snow in the Ny-Ålesund area on the Br∅gger peninsula, Svalbard (N 78°55’ / E 11° 55’). The TerraSAR-X satellite (DLR, Germany) operated at X-band (3.1 cm, 9.6 GHz) with dual co-pol mode (HH/VV) at 5-m spatial resolution, and with high incidence angles (36° to 39°) poviding a better snow penetration and reducing topographic constraints. A dataset of 92 images (ascending and descending) is available since 2017, together with a high resolution DEM (NPI 5-m) and consistent in-situ measurements of meteorological data and snow profiles including glaciers sites. Polarimetric processing is based on the Kennaugh matrix decomposition, copolar phase coherence (CCOH) and copolar phase difference (CPD). The Kennaugh matrix elements K0, K3, K4, and K7 are, respectively, the total intensity, phase ratio, intensity ratio, and shift between HH and VV phase center. Their interpretation allows analysing the structure of the snowpack linked to the near real time of in-situ measurements (snow profiles). The X-band signal is strongly influenced by the snow stratigraphy: internal ice layers reduce or block the penetration of the signal into the snow pack. The best R2 correlation performances between estimated and measured snow heights are ranging from 0.50 to 0.70 for dry snow conditions. Therefore, the use of the X-band for regular snow height estimations remains limited under these conditions. Conversely, this study shows the benefit of TerraSAR-X thanks to the Kennaugh matrix elements analysis. A focus is set on the Copolar Phase Difference (CPD, Leinss 2016) between VV and HH polarization: Φ CPD = Φ VV – Φ HH. Our results indicate that the CPD values are related to the snow metamorphism: positive values correspond to dry snow (horizontal structures), negative values indicate recrystallization processes (vertical structures). Backscattering evolution in time offer a good proxy for meteorological events detection, impacting on snow metamorphism. Fresh snowfalls or melting processes can then be retrieved at the regional scale and linked to air temperature or precipitation measurements at local scale. Polarimetric SAR time series is therefore of interest to complement satellite-based precipitation measurements in the Arctic.
Programme: 1126
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