Tammy E. Davies, Ana P.B. Carneiro, Marguerite Tarzia, Ewan Wakefield, Janos C. Hennicke, Morten Frederiksen, Erpur Snær Hansen, Bruna Campos, Carolina Hazin, Ben Lascelles, Tycho Anker-Nilssen, Hólmfríður Arnardóttir, Robert T. Barrett, Manuel Biscoito, Loïc Bollache, Thierry Boulinier, Paulo Catry, Filipe R. Ceia, Olivier Chastel, Signe Christensen-Dalsgaard, Marta Cruz-Flores, Jóhannis Danielsen, Francis Daunt, Euan Dunn, Carsten Egevang, Ana Isabel Fagundes, Annette L. Fayet, Jérôme Fort, Robert W. Furness, Olivier Gilg, Jacob González-Solís, José Pedro Granadeiro, David Grémillet, Tim Guilford, Sveinn Are Hanssen, Michael P. Harris, April Hedd, Nicholas Per Huffeldt, Mark Jessopp, Yann Kolbeinsson, Johannes Krietsch, Johannes Lang, Jannie Fries Linnebjerg, Svein-Håkon Lorentsen, Jeremy Madeiros, Ellen Magnusdottir, Mark L. Mallory, Laura McFarlane Tranquilla, Flemming R. Merkel, Teresa Militão, Børge Moe, William A. Montevecchi, Virginia Morera-Pujol, Anders Mosbech, Verónica Neves, Mark A. Newell, Bergur Olsen, Vitor H. Paiva, Hans-Ulrich Peter, Aevar Petersen, Richard A. Phillips, Iván Ramírez, Jaime A. Ramos, Raül Ramos, Robert A. Ronconi, Peter G. Ryan, Niels Martin Schmidt, Ingvar A. Sigurðsson, Benoît Sittler, Harald Steen, Iain J. Stenhouse, Hallvard Strøm, Geir H. R. Systad, Paul Thompson, Thorkell L. Thórarinsson, Rob S.A. van Bemmelen, Sarah Wanless, Francis Zino, Maria P. Dias. (2021). Multispecies tracking reveals a major seabird hotspot in the North Atlantic (Vol. 14). Bachelor's thesis, , .
Abstract: The conservation of migratory marine species, including pelagic seabirds, is challenging because their movements span vast distances frequently beyond national jurisdictions. Here, we aim to identify important aggregations of seabirds in the North Atlantic to inform ongoing regional conservation efforts. Using tracking, phenology, and population data, we mapped the abundance and diversity of 21 seabird species. This revealed a major hotspot associated with a discrete area of the subpolar frontal zone, used annually by 2.9–5 million seabirds from ≥56 colonies in the Atlantic: the first time this magnitude of seabird concentrations has been documented in the high seas. The hotspot is temporally stable and amenable to site-based conservation and is under consideration as a marine protected area by the OSPAR Commission. Protection could help mitigate current and future threats facing species in the area. Overall, our approach provides an exemplar data-driven pathway for future conservation efforts on the high seas.
Keywords: area beyond national jurisdiction Atlantic biologging conservation high seas marine protected area regional seas convention
Programme: 330,333,388,1036
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Vincent Bourret, Amandine Gamble, Jérémy Tornos, Audrey Jaeger, Karine Delord, Christophe Barbraud, Pablo Tortosa, Sarah Kada, Jean-Baptiste Thiebot, Eric Thibault, Hubert Gantelet, Henri Weimerskirch, Romain Garnier, Thierry Boulinier. (2018). Vaccination protects endangered albatross chicks against avian cholera (Vol. 11). Bachelor's thesis, , .
Abstract: Global change is contributing to unprecedented expansions of infectious diseases in wildlife. Recurrent avian cholera outbreaks are causing dramatic chick mortality and population decline in endangered albatross colonies on Amsterdam Island, a critical seabird breeding ground in the Southern Indian Ocean. We manufactured a killed vaccine using a Pasteurella multocida strain isolated from a dead albatross in the field. We used this same bacterial strain to establish a serological assay allowing the monitoring of antibody levels following bird vaccination. Using this vaccine on chicks 2 weeks posthatching caused 100% seroconversion and reduced the death risk by a factor exceeding 2.5, raising fledging probability from 14% to 46%. These results suggest that using a specifically tailored vaccine could be a key tool to effectively protect endangered seabirds from disease outbreaks threatening them with extinction.
Keywords: Amsterdam albatross antibody dynamics autogenous vaccine avian cholera dark-mantled sooty albatross emerging infectious diseases Indian yellow-nosed albatross Pasteurella multocida seabird conservation
Programme: 109,1151
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Helen C. Wheeler, Dominique Berteaux, Chris Furgal, Kevin Cazelles, Nigel G. Yoccoz, David Grémillet. (2019). Identifying key needs for the integration of social–ecological outcomes in arctic wildlife monitoring (Vol. 33). Bachelor's thesis, , .
Abstract: For effective monitoring in social–ecological systems to meet needs for biodiversity, science, and humans, desired outcomes must be clearly defined and routes from direct to derived outcomes understood. The Arctic is undergoing rapid climatic, ecological, social, and economic changes and requires effective wildlife monitoring to meet diverse stakeholder needs. To identify stakeholder priorities concerning desired outcomes of arctic wildlife monitoring, we conducted in-depth interviews with 29 arctic scientists, policy and decision makers, and representatives of indigenous organizations and nongovernmental organizations. Using qualitative content analysis, we identified and defined desired outcomes and documented links between outcomes. Using network analysis, we investigated the structure of perceived links between desired outcomes. We identified 18 desired outcomes from monitoring and classified them as either driven by monitoring information, monitoring process, or a combination of both. Highly cited outcomes were make decisions, conserve, detect change, disseminate, and secure food. These reflect key foci of arctic monitoring. Infrequently cited outcomes (e.g., govern) were emerging themes. Three modules comprised our outcome network. The modularity highlighted the low strength of perceived links between outcomes that were primarily information driven or more derived (e.g., detect change, make decisions, conserve, or secure food) and outcomes that were primarily process driven or more derived (e.g., cooperate, learn, educate). The outcomes expand monitoring community and disseminate created connections between these modules. Key desired outcomes are widely applicable to social–ecological systems within and outside the Arctic, particularly those with wildlife subsistence economies. Attributes and motivations associated with outcomes can guide development of integrated monitoring goals for biodiversity conservation and human needs. Our results demonstrated the disconnect between information- and process-driven goals and how expansion of the monitoring community and improved integration of monitoring stakeholders will help connect information- and process-derived outcomes for effective ecosystem stewardship.
Keywords: accionistas adaptive management análisis de redes cambio climático climate change conocimiento tradicional manejo adaptativo monitoreo científico network analysis scientific monitoring stakeholders traditional knowledge 传统知识 利益相关者 气候变化 科学监测 网络分析 适应性管理
Programme: 388
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Alice Carravieri, Orsolya Vincze, Paco Bustamante, Joshua T. Ackerman, Evan M. Adams, Frédéric Angelier, Olivier Chastel, Yves Cherel, Olivier Gilg, Elena Golubova, Alexander Kitaysky, Katelyn Luff, Chad L. Seewagen, Hallvard Strøm, Alexis P. Will, Glenn Yannic, Mathieu Giraudeau, Jérôme Fort. (2022). Quantitative meta-analysis reveals no association between mercury contamination and body condition in birds (Vol. 97). Bachelor's thesis, , .
Abstract: Mercury contamination is a major threat to the global environment, and is still increasing in some regions despite international regulations. The methylated form of mercury is hazardous to biota, yet its sublethal effects are difficult to detect in wildlife. Body condition can vary in response to stressors, but previous studies have shown mixed effects of mercury on body condition in wildlife. Using birds as study organisms, we provide the first quantitative synthesis of the effect of mercury on body condition in animals. In addition, we explored the influence of intrinsic, extrinsic and methodological factors potentially explaining cross-study heterogeneity in results. We considered experimental and correlative studies carried out in adult birds and chicks, and mercury exposure inferred from blood and feathers. Most experimental investigations (90%) showed a significant relationship between mercury concentrations and body condition. Experimental exposure to mercury disrupted nutrient (fat) metabolism, metabolic rates, and food intake, resulting in either positive or negative associations with body condition. Correlative studies also showed either positive or negative associations, of which only 14% were statistically significant. Therefore, the overall effect of mercury concentrations on body condition was null in both experimental (estimate ± SE = 0.262 ± 0.309, 20 effect sizes, five species) and correlative studies (−0.011 ± 0.020, 315 effect sizes, 145 species). The single and interactive effects of age class and tissue type were accounted for in meta-analytic models of the correlative data set, since chicks and adults, as well as blood and feathers, are known to behave differently in terms of mercury accumulation and health effects. Of the 15 moderators tested, only wintering status explained cross-study heterogeneity in the correlative data set: free-ranging wintering birds were more likely to show a negative association between mercury and body condition. However, wintering effect sizes were limited to passerines, further studies should thus confirm this trend in other taxa. Collectively, our results suggest that (i) effects of mercury on body condition are weak and mostly detectable under controlled conditions, and (ii) body condition indices are unreliable indicators of mercury sublethal effects in the wild. Food availability, feeding rates and other sources of variation that are challenging to quantify likely confound the association between mercury and body condition in natura. Future studies could explore the metabolic effects of mercury further using designs that allow for the estimation and/or manipulation of food intake in both wild and captive birds, especially in under-represented life-history stages such as migration and overwintering.
Keywords: blood body mass energetics fat feather feeding habitat metabolism species
Programme: 109,330,388,1036,1210
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Taiki Adachi, Philip Lovell, James Turnbull, Mike A. Fedak, Baptiste Picard, Christophe Guinet, Martin Biuw, Theresa R. Keates, Rachel R. Holser, Daniel P. Costa, Daniel E. Crocker, Patrick J. O. Miller. (2023). Body condition changes at sea: Onboard calculation and telemetry of body density in diving animals (Vol. 14). Bachelor's thesis, , .
Abstract: The ability of marine mammals to accumulate sufficient lipid energy reserves is vital for mammals' survival and successful reproduction. However, long-term monitoring of at-sea changes in body condition, specifically lipid stores, has only been possible in elephant seals performing prolonged drift dives (low-density lipids alter the rates of depth change while drifting). This approach has limited applicability to other species. Using hydrodynamic performance analysis during transit glides, we developed and validated a novel satellite-linked data logger that calculates real-time changes in body density (∝lipid stores). As gliding is ubiquitous amongst divers, the system can assess body condition in a broad array of diving animals. The tag processes high sampling rate depth and three-axis acceleration data to identify 5 s high pitch angle glide segments at depths >100 m. Body density is estimated for each glide using gliding speed and pitch to quantify drag versus buoyancy forces acting on the gliding animal. We used tag data from 24 elephant seals (Mirounga spp.) to validate the onboard calculation of body density relative to drift rate. The new tags relayed body density estimates over 200 days and documented lipid store accumulation during migration with good correspondence between changes in body density and drift rate. Our study provided updated drag coefficient values for gliding (Cd,f = 0.03) and drifting (Cd,s = 0.12) elephant seals, both substantially lower than previous estimates. We also demonstrated post-hoc estimation of the gliding drag coefficient and body density using transmitted data, which is especially useful when drag parameters cannot be estimated with sufficient accuracy before tag deployment. Our method has the potential to advance the field of marine biology by switching the research paradigm from indirectly inferring animal body condition from foraging effort to directly measuring changes in body condition relative to foraging effort, habitat, ecological factors and anthropogenic stressors in the changing oceans. Expanding the method to account for diving air volumes will expand the system's applicability to shallower-diving (<100 m) species, facilitating real-time monitoring of body condition in a broad range of breath-hold divers.
Keywords: animal health bio-logging body density buoyancy marine mammal real-time monitoring satellite transmission
Programme: 109, 1201
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Stier Antoine, Romestaing Caroline, Schull Quentin, Lefol Emilie, Robin Jean‐Patrice, Roussel Damien, Bize Pierre, Davey Matthew. (2017). How to measure mitochondrial function in birds using red blood cells: a case study in the king penguin and perspectives in ecology and evolution (Vol. 8). Bachelor's thesis, , .
Abstract: Summary Mitochondria are the powerhouse of animal cells. They produce through oxidative phosphorylation more than 90% of the cellular energy (ATP) required for organism's growth, reproduction, and maintenance. Hence, information on mitochondrial function is expected to bring important insights in animal ecology and evolution. Unfortunately, the invasiveness of the procedures required to measure mitochondrial function (e.g. sampling of liver or muscles) has limited its study in wild vertebrate populations so far. Here, we capitalize on the fact that bird red blood cells (RBCs) possess functional mitochondria to describe a minimally invasive approach to study mitochondrial function, using blood samples. In the king penguin, we present a protocol, using a high?resolution respirometry system and specific agonists and antagonists enabling the assessment of mitochondrial function in RBCs. We evaluated the inter?assay repeatability of our measures of mitochondrial function, and tested the influence of sample storage and bird handling time on these measures. We also compared measures of mitochondrial function in RBCs and in the pectoral muscle obtained from the same individuals. Mitochondria from RBCs showed the expected responses to mitochondrial agonists and antagonists, and therefore the protocol presented allows computing effective measures of mitochondrial function. The different measures of RBC mitochondrial function were significantly repeatable, were not affected by the handling time of the bird prior to blood sampling (i.e. stress response), and only minimally affected by the storage time of the sample at 4 °C up to 24 h. Most notably, we showed that mitochondrial parameters measured in RBCs moderately correlated to those measured in the pectoral muscle. This study sheds light on the use of RBCs in birds as a valuable and minimally invasive source of information on mitochondrial function. This approach opens new opportunities to study mitochondrial function in free?living animals and could bring knowledge gains in ecology and evolution. Fish, amphibians and reptiles also possess mitochondria in their RBCs, and the approach presented here could also be applicable to these taxa.
Keywords: erythrocyte high‐resolution respirometry metabolism mitochondria non‐invasive methodology
Programme: 119,131
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Amandine Gamble, Romain Bazire, Karine Delord, Christophe Barbraud, Audrey Jaeger, Hubert Gantelet, Eric Thibault, Camille Lebarbenchon, Erwan Lagadec, Pablo Tortosa, Henri Weimerskirch, Jean-Baptiste Thiebot, Romain Garnier, Jérémy Tornos, Thierry Boulinier. (2020). Predator and scavenger movements among and within endangered seabird colonies: Opportunities for pathogen spread (Vol. 57). Bachelor's thesis, , .
Abstract: The spatial structure of host communities is expected to constrain pathogen spread. However, predators and/or scavengers may connect distant host (sub)populations when foraging. Determining whether some individuals or populations play a prominent role in the spread of pathogens is critical to inform management measures. We explored movements and epidemiological status of brown skuas Stercorarius antarcticus, the only avian terrestrial consumer native of Amsterdam Island (Indian Ocean), to assess whether and how they could be involved in the spread of the bacterium Pasteurella multocida, which recurrently causes avian cholera outbreaks in endangered albatross and penguin species breeding on the island. High proportions of seropositive and DNA-positive individuals for P. multocida indicated that skuas are highly exposed to the pathogen and may be able to transmit it. Movement tracking revealed that the foraging ranges of breeding skuas largely overlap among individuals and expand all along the coasts where albatrosses and penguins nest, but not on the inland plateau hosting the endemic Amsterdam albatross Diomedea amsterdamensis. Considering the epidemiological and movement data, skua movements may provide opportunity for pathogen spread among and within seabird colonies. Synthesis and applications. This work highlights the importance of considering the behaviour and epidemiological status of predators and scavengers in disease dynamics because the foraging movements of individuals of such species can potentially limit the efficiency of local management measures in spatially structured host communities. Such species could thus represent priority vaccination targets to implement efficient management measures aiming at limiting pathogen spread and also be used as sentinels to monitor pathogen circulation and evaluate the effectiveness of management measures.
Keywords: conservation biology disease ecology dynamic space utilization individual heterogeneity movement ecology Pasteurella multocida sentinel species serology
Programme: 109,1151
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Florian Orgeret, Ryan R. Reisinger, Tegan Carpenter-Kling, Danielle Z. Keys, Alexandre Corbeau, Charles-André Bost, Henri Weimerskirch, Pierre A. Pistorius. (2021). Spatial segregation in a sexually dimorphic central place forager: Competitive exclusion or niche divergence? (Vol. 90). Bachelor's thesis, , .
Abstract: Sexual competition is increasingly recognized as an important selective pressure driving species distributions. However, few studies have investigated the relative importance of interpopulation versus intrapopulation competition in relation to habitat availability and selection. To explain spatial segregation between sexes that often occurs in non-territorial and central place foragers, such as seabirds, two hypotheses are commonly used. The ‘competitive exclusion’ hypothesis states that dominant individuals should exclude subordinate individuals through direct competition, whereas the ‘niche divergence’ hypothesis states that segregation occurs due to past competition and habitat specialization. We tested these hypotheses in two populations of an extreme wide-ranging and sexually dimorphic seabird, investigating the relative role of intrapopulation and interpopulation competition in influencing sex-specific distribution and habitat preferences. Using GPS loggers, we tracked 192 wandering albatrosses Diomedea exulans during four consecutive years (2016–2019), from two neighbouring populations in the Southern Ocean (Prince Edward and Crozet archipelagos). We simulated pseudo-tracks to create a null spatial distribution and used Kernel Density Estimates (KDE) and Resource Selection Functions (RSF) to distinguish the relative importance of within- versus between-population competition. Kernel Density Estimates showed that only intrapopulation sexual segregation was significant for each monitoring year, and that tracks between the two colonies resulted in greater overlap than expected from the null distribution, especially for the females. RSF confirmed these results and highlighted key at-sea foraging areas, even if the estimated of at-sea densities were extremely low. These differences in selected areas between sites and sexes were, however, associated with high interannual variability in habitat preferences, with no clear specific preferences per site and sex. Our results suggest that even with low at-sea population densities, historic intrapopulation competition in wide-ranging seabirds may have led to sexual dimorphism and niche specialization, favouring the ‘niche divergence’ hypothesis. In this study, we provide a protocol to study competition within as well as between populations of central place foragers. This is relevant for understanding their distribution patterns and population regulation, which could potentially improve management of threatened populations.
Keywords: bio-logging central place foraging ecological niche theory intraspecific competition kernel density estimates resource selection functions sexual segregation wandering albatross
Programme: 109,394
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Garnier Romain, Ramos Raül, Sanz‐Aguilar Ana, Poisbleau Maud, Weimerskirch Henri, Burthe Sarah, Tornos Jeremy, Boulinier Thierry, Fox Charles. (2017). Interpreting ELISA analyses from wild animal samples: Some recurrent issues and solutions (Vol. 31). Bachelor's thesis, , .
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Leduc-Leballeur Marion, Picard Ghislain, Mialon Arnaud, Arnaud Laurent, Lefebvre Eric, Possenti Philippe, Kerr Yann, . (2015). Modeling L-Band Brightness Temperature at Dome C in Antarctica and Comparison With SMOS Observations (Vol. 53). Bachelor's thesis, , .
Abstract: Two electromagnetic models were used to simulate snow emission at L-band from in situ measurements of snow properties collected at Dome C in Antarctica. Two different approaches were used: one based on the radiative transfer theory and the other on the wave approach. The soil moisture ocean salinity (SMOS) satellite observations performed at 1.4 GHz (21 cm) were used to check the validity of these models. Model results based on the wave approach were in good agreement with SMOS observations, particularly for incidence angles lower than 55°. Comparisons suggest that the wave approach is more suitable to simulate brightness temperature at L-band than the transfer radiative theory, because interference between the layers of the snowpack is better taken into account. The model based on the wave approach was then used to investigate several L-band characteristics at Dome C. The emission e-folding depth, i.e., 67% of the signal, was estimated at 250 m, and 99% of the signal emanated from the top 900 m. L-band brightness temperature is only slightly affected by seasonal variations in surface temperature, confirming the high temporal stability of snow emission at low frequency. Sensitivity tests showed that good knowledge of density variability in the snowpack is essential for accurate simulations in L-band.
Keywords: Antarctica, Brightness temperature, Dome C, Ice, L-band, L-band brightness temperature, L-band characteristics, Microwave, SMOS observations, Scattering, Snow, Temperature measurement, brightness suggest snowpack, emission e-folding depth, hydrological techniques, incidence angles, ocean waves, radiative transfer, radiative transfer (RT) theory, radiative transfer theory, remote sensing, seasonal variations, snow, snow emission stability, snow properties, snowpack variability density, soil, soil moisture ocean salinity satellite observation, wave approach, wave theory,
Programme: 1073,1110
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