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Liubomira Romanova, Charles Stépanoff, Norbert Telmon, Eric Crubézy. (2020). Health access inequities and magic medicine: the first ancient evidence? (Vol. 395). Bachelor's thesis, Elsevier, .
Abstract: Inequities in access to the latest advances in health care and effective drugs constitute public health problems today,1 but was this also the case in ancient societies when practitioners used traditional medicines with limited means? The excavation of frozen graves in Yakutia (present day eastern Siberia, Russia) dating from 1700 CE2 led to the identification of a woman, buried almost naked, covered with a magnificent robe and with half a horse bit in her mouth (figure). The other half of the horse bit was found in the trunk behind her head with her earrings, bracelets, and signet rings.
Programme: 1038
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Sam L. Cox, Matthieu Authier, Florian Orgeret, Henri Weimerskirch, Christophe Guinet. (2020). High mortality rates in a juvenile free-ranging marine predator and links to dive and forage ability (Vol. 10). Bachelor's thesis, , .
Abstract: High juvenile mortality rates are typical of many long-lived marine vertebrate predators. Insufficient development in dive and forage ability is considered a key driver of this. However, direct links to survival outcome are sparse, particularly in free-ranging marine animals that may not return to land. In this study, we conduct exploratory investigations toward early mortality in juvenile southern elephant seals Mirounga leonina. Twenty postweaning pups were equipped with (a) a new-generation satellite relay data tag, capable of remotely transmitting fine-scale behavioral movements from accelerometers, and (b) a location transmitting only tag (so that mortality events could be distinguished from device failures). Individuals were followed during their first trip at sea (until mortality or return to land). Two analyses were conducted. First, the behavioral movements and encountered environmental conditions of nonsurviving pups were individually compared to temporally concurrent observations from grouped survivors. Second, common causes of mortality were investigated using Cox's proportional hazard regression and penalized shrinkage techniques. Nine individuals died (two females and seven males) and 11 survived (eight females and three males). All but one individual died before the return phase of their first trip at sea, and all but one were negatively buoyant. Causes of death were variable, although common factors included increased horizontal travel speeds and distances, decreased development in dive and forage ability, and habitat type visited (lower sea surface temperatures and decreased total [eddy] kinetic energy). For long-lived marine vertebrate predators, such as the southern elephant seal, the first few months of life following independence represent a critical period, when small deviations in behavior from the norm appear sufficient to increase mortality risk. Survival rates may subsequently be particularly vulnerable to changes in climate and environment, which will have concomitant consequences on the demography and dynamics of populations.
Keywords: bio-logging early life foraging ecology juvenile mortality Mirounga leonina southern elephant seal survival analyses
Programme: 109,1201
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Ross J. Turner, Martin Gal, Mark A. Hemer, Anya M. Reading. (2020). Impacts of the Cryosphere and Atmosphere on Observed Microseisms Generated in the Southern Ocean (Vol. 125).
Abstract: The Southern Ocean (in the region 60–180° E) south of the Indian Ocean, Australia, and the West Pacific is noted for the frequent occurrence and severity of its storms. These storms give rise to high-amplitude secondary microseisms from sources, including the deep ocean regions, and primary microseisms where the swells impinge on submarine topographic features. A better understanding of the varying microseism wavefield enables improvements to seismic imaging and development of proxy observables to complement sparse in situ wave observations and hindcast models of the global ocean wave climate. We analyze 12–26 years of seismic data from 11 seismic stations either on the East Antarctic coast or sited in the Indian Ocean, Australia, and New Zealand. The power spectral density of the seismic wavefield is calculated to explore how the time-changing microseism intensity varies with (i) sea ice coverage surrounding Antarctica and (ii) the Southern Annular Mode (SAM) climate index. Variations in sea ice extent are found to be the dominant control on the microseism intensity at Antarctic stations, which exhibit a seasonal pattern phase-shifted by 4–5 months compared to stations in other continents. Peaks in extremal intensity at East Antarctic stations occur in March–April, with the highest peaks for secondary microseisms occurring during negative SAM events. This relationship between microseism intensity and the SAM index is opposite to that observed on the Antarctic Peninsula. This work informs the complexity of microseism amplitudes in the Southern Hemisphere and assists ongoing interdisciplinary investigations of interannual variability and long-term trends.
Programme: 133
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Frédéric Angelier, Olivier Chastel, Adam Z. Lendvai, Charline Parenteau, Henri Weimerskirch, John C. Wingfield. (2020). When do older birds better resist stress? A study of the corticosterone stress response in snow petrels (Vol. 16). Bachelor's thesis, Royal Society, .
Abstract: Life-history theory predicts that, to optimize their fitness, individuals should increase their reproductive effort as their residual reproductive value decreases. Accordingly, several studies have shown that individuals downregulate their glucocorticoid stress response (a proxy of reproductive investment in vertebrates) as they age, and as the subsequent reproductive value decreases. However, and surprisingly, results appear inconsistent, suggesting that the environmental context or the individual state may affect the relationship between age and reproductive effort. Here, we tested for the first time this hypothesis, and more specifically, whether this attenuation of the corticosterone stress response with advancing age depends on the energetic status of individuals. We compared the influence of age on the corticosterone stress response between fasting and non-fasting breeding snow petrels (Pagodroma nivea), an extremely long-lived bird. As expected, we found that the corticosterone stress response was attenuated in old petrels, but only when they were not fasting. Interestingly, this pattern was not apparent in fasting petrels, suggesting that old birds downregulate their corticosterone stress response and increase their parental investment only when they are in good body condition. At the ultimate level, old individuals may maintain a strong corticosterone stress response when fasting because the survival costs of increased stress resistance and parental effort might then outweigh their reproductive benefits.
Programme: 109
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Vojtěch Brlík, Jaroslav Koleček, Malcolm Burgess, Steffen Hahn, Diana Humple, Miloš Krist, Janne Ouwehand, Emily L. Weiser, Peter Adamík, José A. Alves, Debora Arlt, Sanja Barišić, Detlef Becker, Eduardo J. Belda, Václav Beran, Christiaan Both, Susana P. Bravo, Martins Briedis, Bohumír Chutný, Davor Ćiković, Nathan W. Cooper, Joana S. Costa, Víctor R. Cueto, Tamara Emmenegger, Kevin Fraser, Olivier Gilg, Marina Guerrero, Michael T. Hallworth, Chris Hewson, Frédéric Jiguet, James A. Johnson, Tosha Kelly, Dmitry Kishkinev, Michel Leconte, Terje Lislevand, Simeon Lisovski, Cosme López, Kent P. McFarland, Peter P. Marra, Steven M. Matsuoka, Piotr Matyjasiak, Christoph M. Meier, Benjamin Metzger, Juan S. Monrós, Roland Neumann, Amy Newman, Ryan Norris, Tomas Pärt, Václav Pavel, Noah Perlut, Markus Piha, Jeroen Reneerkens, Christopher C. Rimmer, Amélie Roberto‐Charron, Chiara Scandolara, Natalia Sokolova, Makiko Takenaka, Dirk Tolkmitt, Herman van Oosten, Arndt H. J. Wellbrock, Hazel Wheeler, Jan van der Winden, Klaudia Witte, Bradley K. Woodworth, Petr Procházka. (2020). Weak effects of geolocators on small birds: A meta-analysis controlled for phylogeny and publication bias (Vol. 89).
Abstract: Currently, the deployment of tracking devices is one of the most frequently used approaches to study movement ecology of birds. Recent miniaturization of light-level geolocators enabled studying small bird species whose migratory patterns were widely unknown. However, geolocators may reduce vital rates in tagged birds and may bias obtained movement data. There is a need for a thorough assessment of the potential tag effects on small birds, as previous meta-analyses did not evaluate unpublished data and impact of multiple life-history traits, focused mainly on large species and the number of published studies tagging small birds has increased substantially. We quantitatively reviewed 549 records extracted from 74 published and 48 unpublished studies on over 7,800 tagged and 17,800 control individuals to examine the effects of geolocator tagging on small bird species (body mass <100 g). We calculated the effect of tagging on apparent survival, condition, phenology and breeding performance and identified the most important predictors of the magnitude of effect sizes. Even though the effects were not statistically significant in phylogenetically controlled models, we found a weak negative impact of geolocators on apparent survival. The negative effect on apparent survival was stronger with increasing relative load of the device and with geolocators attached using elastic harnesses. Moreover, tagging effects were stronger in smaller species. In conclusion, we found a weak effect on apparent survival of tagged birds and managed to pinpoint key aspects and drivers of tagging effects. We provide recommendations for establishing matched control group for proper effect size assessment in future studies and outline various aspects of tagging that need further investigation. Finally, our results encourage further use of geolocators on small bird species but the ethical aspects and scientific benefits should always be considered.
Keywords: condition migration phenology reproduction return rate survival tag effect tracking device
Programme: 1036
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Hannah Joy Kriesell, Céline Le Bohec, Alexander F. Cerwenka, Moritz Hertel, Jean-Patrice Robin, Bernhard Ruthensteiner, Manfred Gahr, Thierry Aubin, Daniel Normen Düring. (2020). Vocal tract anatomy of king penguins: morphological traits of two-voiced sound production (Vol. 17). Bachelor's thesis, , .
Abstract: The astonishing variety of sounds that birds can produce has been the subject of many studies aiming to identify the underlying anatomical and physical mechanisms of sound production. An interesting feature of some bird vocalisations is the simultaneous production of two different frequencies. While most work has been focusing on songbirds, much less is known about dual-sound production in non-passerines, although their sound production organ, the syrinx, would technically allow many of them to produce “two voices”. Here, we focus on the king penguin, a colonial seabird whose calls consist of two fundamental frequency bands and their respective harmonics. The calls are produced during courtship and for partner and offspring reunions and encode the birds’ identity. We dissected, μCT-scanned and analysed the vocal tracts of six adult king penguins from Possession Island, Crozet Archipelago.
Programme: 119,137
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Helle A. Pedersen, Nicolas Leroy, Dimitri Zigone, Martin Vallée, Adam T. Ringler, David C. Wilson. (2020). Using Component Ratios to Detect Metadata and Instrument Problems of Seismic Stations: Examples from 18 Yr of GEOSCOPE Data (Vol. 91).
Abstract: Replacement or deterioration of seismic instruments and the evolution of the installation conditions and sites can alter the seismic signal in very subtle ways; therefore, it is notoriously difficult to monitor the signal quality of permanent seismic stations. We present a simple way to characterize and monitor signal quality, using energy ratios between each pair of the three components, as a complement to existing methods. To calculate stable daily energy ratios over a large frequency range (0.01–5 Hz), we use the daily median energy ratio over all 5 min windows within the day. The method is applied to all GEOSCOPE stations, for continuous BH channel data collected since 2001. We show applications to identify past gain problems (stations ROCAM and CRZF), to provide feedback after field interventions at remote sites (Antarctic station DRV), and to shed light on complex instrument problems (stations ECH and KIP). Our results show that component energy ratios have excellent time resolution and that they are visually simple for identification of problems. They can be used both for ongoing continuous monitoring of the signal quality, or as a tool to identify past problems. The Python code to produce the results in this work and the Python code for daily monitoring used by GEOSCOPE are available (see Data and Resources).
Programme: 133
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Mark A. Hindell, Ryan R. Reisinger, Yan Ropert-Coudert, Luis A. Hückstädt, Philip N. Trathan, Horst Bornemann, Jean-Benoît Charrassin, Steven L. Chown, Daniel P. Costa, Bruno Danis, Mary-Anne Lea, David Thompson, Leigh G. Torres, Anton P. Van de Putte, 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, Stuart Corney, 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, Michael E. 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, Simon Wotherspoon, Ian D. Jonsen, Ben Raymond. (2020). Tracking of marine predators to protect Southern Ocean ecosystems (Vol. 580). Bachelor's thesis, , .
Abstract: Southern Ocean ecosystems are under pressure from resource exploitation and climate change1,2. Mitigation requires the identification and protection of Areas of Ecological Significance (AESs), which have so far not been determined at the ocean-basin scale. Here, using assemblage-level tracking of marine predators, we identify AESs for this globally important region and assess current threats and protection levels. Integration of more than 4,000 tracks from 17 bird and mammal species reveals AESs around sub-Antarctic islands in the Atlantic and Indian Oceans and over the Antarctic continental shelf. Fishing pressure is disproportionately concentrated inside AESs, and climate change over the next century is predicted to impose pressure on these areas, particularly around the Antarctic continent. At present, 7.1% of the ocean south of 40°S is under formal protection, including 29% of the total AESs. The establishment and regular revision of networks of protection that encompass AESs are needed to provide long-term mitigation of growing pressures on Southern Ocean ecosystems.
Programme: 394,1091,1182,1201
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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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Stéphanie Jenouvrier, Marika Holland, David Iles, Sara Labrousse, Laura Landrum, Jimmy Garnier, Hal Caswell, Henri Weimerskirch, Michelle LaRue, Rubao Ji, Christophe Barbraud. (2020). The Paris Agreement objectives will likely halt future declines of emperor penguins (Vol. 26).
Abstract: The Paris Agreement is a multinational initiative to combat climate change by keeping a global temperature increase in this century to 2°C above preindustrial levels while pursuing efforts to limit the increase to 1.5°C. Until recently, ensembles of coupled climate simulations producing temporal dynamics of climate en route to stable global mean temperature at 1.5 and 2°C above preindustrial levels were not available. Hence, the few studies that have assessed the ecological impact of the Paris Agreement used ad-hoc approaches. The development of new specific mitigation climate simulations now provides an unprecedented opportunity to inform ecological impact assessments. Here we project the dynamics of all known emperor penguin (Aptenodytes forsteri) colonies under new climate change scenarios meeting the Paris Agreement objectives using a climate-dependent-metapopulation model. Our model includes various dispersal behaviors so that penguins could modulate climate effects through movement and habitat selection. Under business-as-usual greenhouse gas emissions, we show that 80% of the colonies are projected to be quasiextinct by 2100, thus the total abundance of emperor penguins is projected to decline by at least 81% relative to its initial size, regardless of dispersal abilities. In contrast, if the Paris Agreement objectives are met, viable emperor penguin refuges will exist in Antarctica, and only 19% and 31% colonies are projected to be quasiextinct by 2100 under the Paris 1.5 and 2 climate scenarios respectively. As a result, the global population is projected to decline by at least by 31% under Paris 1.5 and 44% under Paris 2. However, population growth rates stabilize in 2060 such that the global population will be only declining at 0.07% under Paris 1.5 and 0.34% under Paris 2, thereby halting the global population decline. Hence, global climate policy has a larger capacity to safeguard the future of emperor penguins than their intrinsic dispersal abilities.
Keywords: Antarctica climate change mitigation dispersion emission reduction pledges seabirds
Programme: 109
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