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Cornioley Tina, Börger Luca, Ozgul Arpat, Weimerskirch Henri, Gill Jennifer. (2016). Impact of changing wind conditions on foraging and incubation success in male and female wandering albatrosses (Vol. 85).
Abstract: Summary Wind is an important climatic factor for flying animals as by affecting their locomotion, it can deeply impact their life?history characteristics. In the context of globally changing wind patterns, we investigated the mechanisms underlying recently reported increase in body mass of a population of wandering albatrosses (Diomedea exulans) with increasing wind speed over time. We built a foraging model detailing the effects of wind on movement statistics and ultimately on mass gained by the forager and mass lost by the incubating partner. We then simulated the body mass of incubating pairs under varying wind scenarios. We tracked the frequency at which critical mass leading to nest abandonment was reached to assess incubation success. We found that wandering albatrosses behave as time minimizers during incubation as mass gain was independent of any movement statistics but decreased with increasing mass at departure. Individuals forage until their energy requirements, which are determined by their body conditions, are fulfilled. This can come at the cost of their partner's condition as mass loss of the incubating partner depended on trip duration. This behaviour is consistent with strategies of long?lived species which favoured their own survival over their current reproductive attempt. In addition, wind speed increased ground speed which in turn reduced trip duration and males foraged further away than females at high ground speed. Contrasted against an independent data set, the simulation performed satisfactorily for males but less so for females under current wind conditions. The simulation predicted an increase in male body mass growth rate with increasing wind speed, whereas females' rate decreased. This trend may provide an explanation for the observed increase in mass of males but not of females. Conversely, the simulation predicted very few nest abandonments, which is in line with the high breeding success of this species and is contrary to the hypothesis that wind patterns impact incubation success by altering foraging movement.
Keywords: breeding success energy maximizer environmental changes resource acquisition resource allocation time minimizer
Programme: 109
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Cornioley Tina, Jenouvrier Stéphanie, Börger Luca, Weimerskirch Henri, Ozgul Arpat. (2017). Fathers matter: male body mass affects life-history traits in a size-dimorphic seabird (Vol. 284).
Abstract: One of the predicted consequences of climate change is a shift in body mass distributions within animal populations. Yet body mass, an important component of the physiological state of an organism, can affect key life-history traits and consequently population dynamics. Over the past decades, the wandering albatross—a pelagic seabird providing bi-parental care with marked sexual size dimorphism—has exhibited an increase in average body mass and breeding success in parallel with experiencing increasing wind speeds. To assess the impact of these changes, we examined how body mass affects five key life-history traits at the individual level: adult survival, breeding probability, breeding success, chick mass and juvenile survival. We found that male mass impacted all traits examined except breeding probability, whereas female mass affected none. Adult male survival increased with increasing mass. Increasing adult male mass increased breeding success and mass of sons but not of daughters. Juvenile male survival increased with their chick mass. These results suggest that a higher investment in sons by fathers can increase their inclusive fitness, which is not the case for daughters. Our study highlights sex-specific differences in the effect of body mass on the life history of a monogamous species with bi-parental care.
Programme: 109
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Cox Sam L., Orgeret Florian, Gesta Mathieu, Rodde Charles, Heizer Isaac, Weimerskirch Henri, Guinet Christophe, O'Hara Robert B. (2017). Processing of acceleration and dive data on‐board satellite relay tags to investigate diving and foraging behaviour in free‐ranging marine predators (Vol. 9).
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Creasy Neala, Long Maureen D., Ford Heather A. (2017). Deformation in the lowermost mantle beneath Australia from observations and models of seismic anisotropy (Vol. 122).
Abstract: Abstract Observations of seismic anisotropy near the core?mantle boundary may yield constraints on patterns of lowermost mantle flow. We examine seismic anisotropy in the lowermost mantle beneath Australia, bounded by the African and Pacific Large Low Shear Velocity Provinces. We combined measurements of differential splitting of SKS?SKKS and S?ScS phases sampling our study region over a range of azimuths, using data from 10 long?running seismic stations. Observations reveal complex and laterally heterogeneous anisotropy in the lowermost mantle. We identified two subregions for which we have robust measurements of D??associated splitting for a range of ray propagation directions and applied a forward modeling strategy to understand which anisotropic scenarios are consistent with the observations. We tested a variety of elastic tensors and orientations, including single?crystal elasticity of lowermost mantle minerals (bridgmanite, postperovskite, and ferropericlase), tensors based on texture modeling in postperovskite aggregates, elasticity predicted from deformation experiments on polycrystalline MgO aggregates, and tensors that approximate the shape preferred orientation of partial melt. We find that postperovskite scenarios are more consistently able to reproduce the observations. Beneath New Zealand, the observations suggest a nearly horizontal [100] axis orientation with an azimuth that agrees well with the horizontal flow direction predicted by previous mantle flow models. Our modeling results further suggest that dominant slip on the (010) plane in postperovskite aggregates provides a good fit to the data but the solution is nonunique. Our results have implications for the mechanisms of deformation and anisotropy in the lowermost mantle and for the patterns of mantle flow.
Keywords: anisotropy lowermost mantle mantle dynamics postperovskite shear wave splitting
Programme: 133
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Duncan A. Young, Laura E. Lindzey, Donald D. Blankenship, Jamin S. Greenbaum1 and Emmanuel Le Meur. (2013). Ice surface elevation change on the George V Coast of East Antarctica: a new hybrid high resolution record, in Strategic Science in Antarctica
A joint Australian and New Zealand conference
24 – 26 June 2013 . Hobart, Tasmania.
Abstract: Oral presentation
Programme: 1053
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Duron Olivier, Binetruy Florian, Noël Valérie, Cremaschi Julie, McCoy Karen D., Arnathau Céline, Plantard Olivier, Goolsby John, Pérez de León Adalberto A., Heylen Dieter J. A., Van Oosten A. Raoul, Gottlieb Yuval, Baneth Gad, Guglielmone Alberto A., Estrada‐Peña Agustin, Opara Maxwell N., Zenner Lionel, Vavre Fabrice, Chevillon Christine. (2017). Evolutionary changes in symbiont community structure in ticks (Vol. 26).
Abstract: Abstract Ecological specialization to restricted diet niches is driven by obligate, and often maternally inherited, symbionts in many arthropod lineages. These heritable symbionts typically form evolutionarily stable associations with arthropods that can last for millions of years. Ticks were recently found to harbour such an obligate symbiont, Coxiella?LE, that synthesizes B vitamins and cofactors not obtained in sufficient quantities from blood diet. In this study, the examination of 81 tick species shows that some Coxiella?LE symbioses are evolutionarily stable with an ancient acquisition followed by codiversification as observed in ticks belonging to the Rhipicephalus genus. However, many other Coxiella?LE symbioses are characterized by low evolutionary stability with frequent host shifts and extinction events. Further examination revealed the presence of nine other genera of maternally inherited bacteria in ticks. Although these nine symbionts were primarily thought to be facultative, their distribution among tick species rather suggests that at least four may have independently replaced Coxiella?LE and likely represent alternative obligate symbionts. Phylogenetic evidence otherwise indicates that cocladogenesis is globally rare in these symbioses as most originate via horizontal transfer of an existing symbiont between unrelated tick species. As a result, the structure of these symbiont communities is not fixed and stable across the tick phylogeny. Most importantly, the symbiont communities commonly reach high levels of diversity with up to six unrelated maternally inherited bacteria coexisting within host species. We further conjecture that interactions among coexisting symbionts are pivotal drivers of community structure both among and within tick species.
Keywords: co‐evolution heritable symbiont communities maternally inherited bacteria symbiosis tick
Programme: 333
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Eidesen Pernille Bronken, Ehrich Dorothee, Bakkestuen Vegar, Alsos Inger Greve, Gilg Oliver, Taberlet Pierre, Brochmann Christian. (2013). Genetic roadmap of the Arctic: plant dispersal highways, traffic barriers and capitals of diversity (Vol. 200). Bachelor's thesis, , .
Abstract: Summary We provide the first comparative multispecies analysis of spatial genetic structure and diversity in the circumpolar Arctic using a common strategy for sampling and genetic analyses. We aimed to identify and explain potential general patterns of genetic discontinuity/connectivity and diversity, and to compare our findings with previously published hypotheses. We collected and analyzed 7707 samples of 17 widespread arctic?alpine plant species for amplified fragment length polymorphisms (AFLPs). Genetic structure, diversity and distinctiveness were analyzed for each species, and extrapolated to cover the geographic range of each species. The resulting maps were overlaid to produce metamaps. The Arctic and Atlantic Oceans, the Greenlandic ice cap, the Urals, and lowland areas between southern mountain ranges and the Arctic were the strongest barriers against gene flow. Diversity was highest in Beringia and gradually decreased into formerly glaciated areas. The highest degrees of distinctiveness were observed in Siberia. We conclude that large?scale general patterns exist in the Arctic, shaped by the Pleistocene glaciations combined with long?standing physical barriers against gene flow. Beringia served as both refugium and source for interglacial (re)colonization, whereas areas further west in Siberia served as refugia, but less as sources for (re)colonization.
Keywords: amplified fragment length polymorphisms (AFLP) Arctic comparative phylogeography genetic diversity genetic structure geographical information system (GIS) plant dispersal refugia
Programme: 1036
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Fay Rémi, Barbraud Christophe, Delord Karine, Weimerskirch Henri. (2016). Variation in the age of first reproduction: different strategies or individual quality? (Vol. 97).
Abstract: Abstract Although age at first reproduction is a key demographic parameter that is probably under high selective pressure, it is highly variable and the cause of this variability is not well understood. Two non?exclusive hypotheses may explain such variability. It could be the expression of different individual strategies, i.e., different allocation strategies in fitness components, or the consequences of individual difference in intrinsic quality, i.e., some individuals always doing better than others in all fitness components. We tested these hypotheses in the Wandering Albatross investigating relationships between the age at first reproduction and subsequent adult demographic traits. Using finite mixture capture recapture modeling, we demonstrate that the age at first reproduction is negatively related to both reproductive performances and adult survival, suggesting that individual quality was an important factor explaining variation in the age at first reproduction. Our results suggest that age at first breeding is a good predictor of quality in this long?lived seabird species.
Keywords: capture–mark–recapture individual heterogeneity life‐history plasticity reaction norm trade‐off Wandering Albatross
Programme: 109
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Fay Rémi, Barbraud Christophe, Delord Karine, Weimerskirch Henri. (2017). From early life to senescence: individual heterogeneity in a long‐lived seabird (Vol. 88).
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Fay Rémi, Barbraud Christophe, Delord Karine, Weimerskirch Henri, Costa Daniel. (2017). Contrasting effects of climate and population density over time and life stages in a long‐lived seabird (Vol. 31).
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