|
Maxime Allioux, Stéven Yvenou, Alexander Merkel, Marc Cozannet, Johanne Aubé, Jolann Pommellec, Marc Le Romancer, Véronique Lavastre, Damien Guillaume, Karine Alain. (2022). A metagenomic insight into the microbiomes of geothermal springs in the Subantarctic Kerguelen Islands (Vol. 12).
Abstract: The Kerguelen Islands, located in the southern part of the Indian Ocean, are very isolated geographically. The microbial diversity and communities present on the island, especially associated to geothermal springs, have never been analyzed with high-throughput sequencing methods. In this article, we performed the first metagenomics analysis of microorganisms present in Kerguelen hot springs. From four hot springs, we assembled metagenomes and recovered 42 metagenome-assembled genomes, mostly associated with new putative taxa based on phylogenomic analyses and overall genome relatedness indices. The 42 MAGs were studied in detail and showed putative affiliations to 13 new genomic species and 6 new genera of Bacteria or Archaea according to GTDB. Functional potential of MAGs suggests the presence of thermophiles and hyperthermophiles, as well as heterotrophs and primary producers possibly involved in the sulfur cycle, notably in the oxidation of sulfur compounds. This paper focused on only four of the dozens of hot springs in the Kerguelen Islands and should be considered as a preliminary study of the microorganisms inhabiting the hot springs of these isolated islands. These results show that more efforts should be made towards characterization of Kerguelen Islands ecosystems, as they represent a reservoir of unknown microbial lineages.
Keywords: Computational biology and bioinformatics Ecology Genetics Microbiology
Programme: 1077
|
|
|
Sophia Ferchiou, France Caza, Richard Villemur, Stéphane Betoulle, Yves St-Pierre. (2022). Species- and site-specific circulating bacterial DNA in Subantarctic sentinel mussels Aulacomya atra and Mytilus platensis (Vol. 12).
Abstract: Impacts of climate changes are particularly severe in polar regions where warmer temperatures and reductions in sea-ice covers threaten the ecological integrity of marine coastal ecosystems. Because of their wide distribution and their ecological importance, mussels are currently used as sentinel organisms in monitoring programs of coastal ecosystems around the world. In the present study, we exploited the concept of liquid biopsy combined to a logistically friendly sampling method to study the hemolymphatic bacterial microbiome in two mussel species (Aulacomya atra and Mytilus platensis) in Kerguelen Islands, a remote Subantarctic volcanic archipelago. We found that the circulating microbiome signatures of both species differ significantly even though their share the same mussel beds. We also found that the microbiome differs significantly between sampling sites, often correlating with the particularity of the ecosystem. Predictive models also revealed that both species have distinct functional microbiota, and that the circulating microbiome of Aulacomya atra was more sensitive to changes induced by acute thermal stress when compared to Mytilus platensis. Taken together, our study suggests that defining circulating microbiome is a useful tool to assess the health status of marine ecosystems and to better understand the interactions between the sentinel species and their habitat.
Keywords: Ecology Microbial ecology
Programme: 1044
|
|
|
Marianna Chimienti, Akiko Kato, Olivia Hicks, Frédéric Angelier, Michaël Beaulieu, Jazel Ouled-Cheikh, Coline Marciau, Thierry Raclot, Meagan Tucker, Danuta Maria Wisniewska, André Chiaradia, Yan Ropert-Coudert. (2022). The role of individual variability on the predictive performance of machine learning applied to large bio-logging datasets (Vol. 12).
Abstract: Animal-borne tagging (bio-logging) generates large and complex datasets. In particular, accelerometer tags, which provide information on behaviour and energy expenditure of wild animals, produce high-resolution multi-dimensional data, and can be challenging to analyse. We tested the performance of commonly used artificial intelligence tools on datasets of increasing volume and dimensionality. By collecting bio-logging data across several sampling seasons, datasets are inherently characterized by inter-individual variability. Such information should be considered when predicting behaviour. We integrated both unsupervised and supervised machine learning approaches to predict behaviours in two penguin species. The classified behaviours obtained from the unsupervised approach Expectation Maximisation were used to train the supervised approach Random Forest. We assessed agreement between the approaches, the performance of Random Forest on unknown data and the implications for the calculation of energy expenditure. Consideration of behavioural variability resulted in high agreement (> 80%) in behavioural classifications and minimal differences in energy expenditure estimates. However, some outliers with < 70% of agreement, highlighted how behaviours characterized by signal similarity are confused. We advise the broad bio-logging community, approaching these large datasets, to be cautious when upscaling predictions, as this might lead to less accurate estimates of behaviour and energy expenditure.
Keywords: Behavioural ecology Ecological modelling Ecophysiology Machine learning
Programme: 1091
|
|
|
Olivia Hicks, Akiko Kato, Frederic Angelier, Danuta M. Wisniewska, Catherine Hambly, John R. Speakman, Coline Marciau, Yan Ropert-Coudert. (2020). Acceleration predicts energy expenditure in a fat, flightless, diving bird (Vol. 10).
Abstract: Energy drives behaviour and life history decisions, yet it can be hard to measure at fine scales in free-moving animals. Accelerometry has proven a powerful tool to estimate energy expenditure, but requires calibration in the wild. This can be difficult in some environments, or for particular behaviours, and validations have produced equivocal results in some species, particularly air-breathing divers. It is, therefore, important to calibrate accelerometry across different behaviours to understand the most parsimonious way to estimate energy expenditure in free-living conditions. Here, we combine data from miniaturised acceleration loggers on 58 free-living Adélie penguins with doubly labelled water (DLW) measurements of their energy expenditure over several days. Across different behaviours, both in water and on land, dynamic body acceleration was a good predictor of independently measured DLW-derived energy expenditure (R2 = 0.72). The most parsimonious model suggested different calibration coefficients are required to predict behaviours on land versus foraging behaviour in water (R2 = 0.75). Our results show that accelerometry can be used to reliably estimate energy expenditure in penguins, and we provide calibration equations for estimating metabolic rate across several behaviours in the wild.
Keywords: Ecology Ecophysiology
Programme: 1091
|
|
|
Melissa L. Grunst, Andrea S. Grunst, David Grémillet, Akiko Kato, Sophie Gentès, Jérôme Fort. (2023). Keystone seabird may face thermoregulatory challenges in a warming Arctic (Vol. 13).
Abstract: Climate change affects the Arctic more than any other region, resulting in evolving weather, vanishing sea ice and altered biochemical cycling, which may increase biotic exposure to chemical pollution. We tested thermoregulatory impacts of these changes on the most abundant Arctic seabird, the little auk (Alle alle). This small diving species uses sea ice-habitats for foraging on zooplankton and resting. We equipped eight little auks with 3D accelerometers to monitor behavior, and ingested temperature recorders to measure body temperature (Tb). We also recorded weather conditions, and collected blood to assess mercury (Hg) contamination. There were nonlinear relationships between time engaged in different behaviors and Tb. Tb increased on sea ice, following declines while foraging in polar waters, but changed little when birds were resting on water. Tb also increased when birds were flying, and decreased at the colony after being elevated during flight. Weather conditions, but not Hg contamination, also affected Tb. However, given our small sample size, further research regarding thermoregulatory effects of Hg is warranted. Results suggest that little auk Tb varies with behavior and weather conditions, and that loss of sea ice due to global warming may cause thermoregulatory and energic challenges during foraging trips at sea.
Keywords: Climate-change ecology Ecophysiology
Programme: 388
|
|
|
Roquet Fabien, Williams Guy, Hindell Mark A, Harcourt Rob, McMahon Clive, Guinet Christophe, Charrassin Jean-Benoit, Reverdin Gilles, Boehme Lars, Lovell Phil, Fedak Mike, . (2014). A Southern Indian Ocean database of hydrographic profiles obtained with instrumented elephant seals.
. Scientific data, 1, 140028.
Abstract: The instrumentation of southern elephant seals with satellite-linked CTD tags has offered unique temporal and spatial coverage of the Southern Indian Ocean since 2004. This includes extensive data from the Antarctic continental slope and shelf regions during the winter months, which is outside the conventional areas of Argo autonomous floats and ship-based studies. This landmark dataset of around 75,000 temperature and salinity profiles from 20-140 °E, concentrated on the sector between the Kerguelen Islands and Prydz Bay, continues to grow through the coordinated efforts of French and Australian marine research teams. The seal data are quality controlled and calibrated using delayed-mode techniques involving comparisons with other existing profiles as well as cross-comparisons similar to established protocols within the Argo community, with a resulting accuracy of ±0.03 °C in temperature and ±0.05 in salinity or better. The data offer invaluable new insights into the water masses, oceanographic processes and provides a vital tool for oceanographers seeking to advance our understanding of this key component of the global ocean climate.
Keywords: Animals, Databases, Factual, Indian Ocean, Oceanography, Oceanography: methods, Seals, Earless,
Programme: 109
|
|
|
Yan Ropert-Coudert, Anton P. Van de Putte, Ryan R. Reisinger, Horst Bornemann, Jean-Benoît Charrassin, Daniel P. Costa, Bruno Danis, Luis A. Hückstädt, Ian D. Jonsen, Mary-Anne Lea, David Thompson, Leigh G. Torres, Philip N. Trathan, Simon Wotherspoon, David G. Ainley, Rachael Alderman, Virginia Andrews-Goff, Ben Arthur, Grant Ballard, John Bengtson, Marthán N. Bester, Arnoldus Schytte Blix, Lars Boehme, Charles-André Bost, Peter Boveng, Jaimie Cleeland, Rochelle Constantine, Robert J. M. Crawford, Luciano Dalla Rosa, P. J. Nico de Bruyn, Karine Delord, Sébastien Descamps, Mike Double, Louise Emmerson, Mike Fedak, Ari Friedlaender, Nick Gales, Mike Goebel, Kimberly T. Goetz, Christophe Guinet, Simon D. Goldsworthy, Rob Harcourt, Jefferson T. Hinke, Kerstin Jerosch, Akiko Kato, Knowles R. Kerry, Roger Kirkwood, Gerald L. Kooyman, Kit M. Kovacs, Kieran Lawton, Andrew D. Lowther, Christian Lydersen, Phil O’B Lyver, Azwianewi B. Makhado, Maria E. I. Márquez, Birgitte I. McDonald, Clive R. McMahon, Monica Muelbert, Dominik Nachtsheim, Keith W. Nicholls, Erling S. Nordøy, Silvia Olmastroni, Richard A. Phillips, Pierre Pistorius, Joachim Plötz, Klemens Pütz, Norman Ratcliffe, Peter G. Ryan, Mercedes Santos, Colin Southwell, Iain Staniland, Akinori Takahashi, Arnaud Tarroux, Wayne Trivelpiece, Ewan Wakefield, Henri Weimerskirch, Barbara Wienecke, José C. Xavier, Ben Raymond, Mark A. Hindell. (2020). The retrospective analysis of Antarctic tracking data project (Vol. 7). Bachelor's thesis, , .
Abstract: The Retrospective Analysis of Antarctic Tracking Data (RAATD) is a Scientific Committee for Antarctic Research project led jointly by the Expert Groups on Birds and Marine Mammals and Antarctic Biodiversity Informatics, and endorsed by the Commission for the Conservation of Antarctic Marine Living Resources. RAATD consolidated tracking data for multiple species of Antarctic meso- and top-predators to identify Areas of Ecological Significance. These datasets and accompanying syntheses provide a greater understanding of fundamental ecosystem processes in the Southern Ocean, support modelling of predator distributions under future climate scenarios and create inputs that can be incorporated into decision making processes by management authorities. In this data paper, we present the compiled tracking data from research groups that have worked in the Antarctic since the 1990s. The data are publicly available through biodiversity.aq and the Ocean Biogeographic Information System. The archive includes tracking data from over 70 contributors across 12 national Antarctic programs, and includes data from 17 predator species, 4060 individual animals, and over 2.9 million observed locations.
Programme: 109,1091,1201
|
|
|
Antoine A., Johnson M.; Labrousse S., Goulet P., Chevallay M., Laborie B., Picard B., Guinet C., Nerini D., Charrassin J.-b., Heerah K. (2023). Beneath the Antarctic sea-ice: Fine-scale analysis of Weddell seal behavior and predator-prey interactions, using micro-sonar data in Terre Adélie..
|
|
|
Stordal F., Derwent F.G., Isaksen I.S.A., Jacob D., Kanakidou M., Logan J.A. & Prather M.J. (1994). Model Simulations of Global Tropospheric Ozone..
Abstract: Scientific Assessment of Ozone Depletion. Chapt. 7
Programme: 146
|
|
|
Duchene J.C., Bhaud M., Cha J.H., Martin D. & Nozais C. (1995). Larval biology and benthic recruitment. New prospects on the role of egg masses and proposai on regulation mortel of the life cycle. Sci. Mar., 59, 103–117.
|
|