Background:Land-use change is one of the main drivers of the global erosion of biodiversity.In that context,it is crucial to understand how landscape characteristics drive the presence of rare endangered species.Never...Background:Land-use change is one of the main drivers of the global erosion of biodiversity.In that context,it is crucial to understand how landscape characteristics drive the presence of rare endangered species.Nevertheless,it is also important to study common species in multiple habitats,because they represent a large proportion of biodiversity and are essential to maintain ecological functions.Interestingly,some habitats,as farmlands with permanent crops(e.g.vineyards),have been overlooked in the literature.Methods:In this study,we investigated the distribution of a widespread and common bird species,the Common Blackbird(Turdus merula),within and between the three main habitats of our study area(rural Western France).We specifically focused on(1)woodlands,(2)farmlands with a high vineyard coverage,and(3)moderately urbanized areas.Specifically,we aimed to assess the beneficial and detrimental effects of these habitats and their fine-scale composition on the presence of a common bird species,relying on a survey by point counts(nearly 100 locations).We studied the effects of habitats and gradients of fine-scale habitat composition on blackbird presence using logistic regression analyses.Results:Blackbirds were present in all studied habitats.However,their presence varied between habitats,being lower in vineyards than in woodlands and cities.In woodlands and cities,fine-scale analyses did not reveal any component driving the species'presence.However,we found that shrub and tree vegetation cover had a significant positive effect on blackbird presence in vineyards.Conclusions:Our results are in agreement with the definition of a generalist species.Interestingly,species distribution varied between habitats.The high presence of blackbirds in urban areas suggests that medium-sized cities,despite their artificialization,do not constrain the settlement of this former forest specialist and that green spaces may allow blackbirds to thrive in medium-sized cities.On the contrary,we found an impoverished presence of blackbirds in vineyards and a positive effect of vegetation on their presence in these landscapes.This suggests that permanent crops,and more generally farmlands,may impose important constraints to common species.Future studies should examine how to enhance biodiversity through agricultural management policies,especially in vineyards.展开更多
Assessing the determinants of reproductive success is critical but often complicated because of complex interactions between parental traits and environmental conditions occurring during several stages of a reproducti...Assessing the determinants of reproductive success is critical but often complicated because of complex interactions between parental traits and environmental conditions occurring during several stages of a reproductive event.Here,we used a simplified ecological situation-an amphibian species lacking post-oviposition parental care-and a laboratory approach to investigate the relationships between parental(both maternal and paternal)phenotypes(body size and condition)and reproductive success(fecundity,egg size,embryonic and larval duration,larval and metamorphic morphology).We found significant effects of maternal phenotype on fecundity,hatching success,and tadpole size,as well as on the duration of larval development.Interestingly,and more surprisingly,we also found a potential contribution of the paternal phenotype occurring during early(embryonic development duration)offspring development.Although our study focused on life-history traits such as body size and development duration,additional mechanisms involving physiological costs of development may well mediate the relationships between parental phenotypes and offspring development.Future studies are required to decipher the mechanisms underlying our findings in order to clarify the mechanistic basis of the links between parental phenotypes and offspring development.展开更多
The vast diversity of morphologies,body size,and lifestyles of snakes represents an important source of information that can be used to derive bio-inspired robots through a biology-push and pull process.An understandi...The vast diversity of morphologies,body size,and lifestyles of snakes represents an important source of information that can be used to derive bio-inspired robots through a biology-push and pull process.An understanding of the detailed kinematics of swimming snakes is a fundamental prerequisite to conceive and design bio-inspired aquatic snake robots.However,only limited information is available on the kinematics of swimming snake.Fast and accurate methods are needed to fill this knowledge gap.In the present paper,three existing methods were compared to test their capacity to characterize the kinematics of swimming snakes.(1)Marker tracking(Deftac),(2)Markerless pose estimation(DeepLabCut),and(3)Motion capture were considered.(4)We also designed and tested an automatic video processing method.All methods provided different albeit complementary data sets;they also involved different technical issues in terms of experimental conditions,snake manipulation,or processing resources.Marker tracking provided accurate data that can be used to calibrate other methods.Motion capture posed technical difficulties but can provide limited 3D data.Markerless pose estimation required deep learning(thus time)but was efficient to extract the data under various experimental conditions.Finally,automatic video processing was particularly efficient to extract a wide range of data useful for both biology and robotics but required a specific experimental setting.展开更多
Bio-loggers are miniaturized autonomous devices that record quantitative data on the state of free-ranging ani-mals(e.g.behavior,position and physiology)and their natural environment.This is especially relevant for sp...Bio-loggers are miniaturized autonomous devices that record quantitative data on the state of free-ranging ani-mals(e.g.behavior,position and physiology)and their natural environment.This is especially relevant for spe-cies where direct visual observation is difficult or impossible.Today,ongoing technical development allows the monitoring of numerous parameters in an increasing range of species over extended periods.However,the ex-ternal attachment of devices might affect various aspects of animal performance(energetics,thermoregulation,foraging as well as social and reproductive behavior),which ultimately affect fitness.External attachment might also increase entanglement risk and the conspicuousness of animals,leaving them more vulnerable to preda-tion.By contrast,implantation of devices can mitigate many of these undesirable effects and might be prefera-ble,especially for long-term studies,provided that the many challenges associated with surgical procedures can be mastered.Implantation may then allow us to gather data that would be impossible to obtain otherwise and thereby may provide new and ecologically relevant insights into the life of wild animals.Here,we:(i)discuss the pros and cons of attachment methods;(ii)highlight recent field studies that used implanted bio-loggers to address eco-physiological questions in a wide range of species;and(iii)discuss logger implantation in light of ethical considerations.展开更多
Contrary to the nestling phase, the post-fledging phase has been less studied probably because it is challenging to follow the chicks after they fledge. However, this phase is crucial to consider when focusing on the ...Contrary to the nestling phase, the post-fledging phase has been less studied probably because it is challenging to follow the chicks after they fledge. However, this phase is crucial to consider when focusing on the life cycle of individuals because it is associated with new demands: After leaving the nest, individuals have to find their own food and cope with a new set of previously unknown stressors. In this study, we aimed at better understanding how energetically demanding the post-ftedging period is in house sparrows Passer domesticus by measuring several indices of a fledgling's state (body condition, fat and muscle scores and plumage quality). If the energetic demands of the post-fledging period are greater than those of the adult life, we predicted that fledglings should be in lower condition and should have a plumage of lower quality relative to adults. Supporting this prediction, the condition and the plumage of fledglings differed dramatically from those of adults. Interestingly, this difference disappeared in autumn. Overall, our results suggest that the post-fledging period is probably one of the most energetically demanding of the life cycle in this species. Supporting this idea, the resighting probability of fledglings was lower relative to adults. However, resighting probability depends on many factors (mortality, dispersal, habitat use and behaviours) and future studies are necessary to tease apart their relative importance in determining resighting probability [Current Zoology 60 (4): 449-459, 2014].展开更多
基金funded by the Agence Nationale de la Recherche(ANR project URBASTRESS,ANR-16-CE02-0004-01 to F.A.,and ANR project VITIBIRD to F.A.)by the Région Nouvelle-Aquitaine(MULTISTRESS project)+1 种基金by the Agence nationale de sécuritésanitaire de l’alimentation,de l’environnement et du travail(ANSES project Biodi Tox#2019/1/031)by the Centre National de la Recherche Scientifique。
文摘Background:Land-use change is one of the main drivers of the global erosion of biodiversity.In that context,it is crucial to understand how landscape characteristics drive the presence of rare endangered species.Nevertheless,it is also important to study common species in multiple habitats,because they represent a large proportion of biodiversity and are essential to maintain ecological functions.Interestingly,some habitats,as farmlands with permanent crops(e.g.vineyards),have been overlooked in the literature.Methods:In this study,we investigated the distribution of a widespread and common bird species,the Common Blackbird(Turdus merula),within and between the three main habitats of our study area(rural Western France).We specifically focused on(1)woodlands,(2)farmlands with a high vineyard coverage,and(3)moderately urbanized areas.Specifically,we aimed to assess the beneficial and detrimental effects of these habitats and their fine-scale composition on the presence of a common bird species,relying on a survey by point counts(nearly 100 locations).We studied the effects of habitats and gradients of fine-scale habitat composition on blackbird presence using logistic regression analyses.Results:Blackbirds were present in all studied habitats.However,their presence varied between habitats,being lower in vineyards than in woodlands and cities.In woodlands and cities,fine-scale analyses did not reveal any component driving the species'presence.However,we found that shrub and tree vegetation cover had a significant positive effect on blackbird presence in vineyards.Conclusions:Our results are in agreement with the definition of a generalist species.Interestingly,species distribution varied between habitats.The high presence of blackbirds in urban areas suggests that medium-sized cities,despite their artificialization,do not constrain the settlement of this former forest specialist and that green spaces may allow blackbirds to thrive in medium-sized cities.On the contrary,we found an impoverished presence of blackbirds in vineyards and a positive effect of vegetation on their presence in these landscapes.This suggests that permanent crops,and more generally farmlands,may impose important constraints to common species.Future studies should examine how to enhance biodiversity through agricultural management policies,especially in vineyards.
基金Funding was provided by the CNRS,the Agence de lʹEau Loire-Bretagne,the Agence de lʹEau Adour-Garonne,the Conseil Départemental des Deux-Sèvres,the Région Nouvelle-Aquitaine(Multistress 2017-1R20110,Aquastress 2018-1R20214,Amphitox 2019-1R20216)the ANSES(BiodiTox project 2019/1/031)the Plan dʹAction National ECOPHYTO(OFB-21-0941),and the CPER Econat.
文摘Assessing the determinants of reproductive success is critical but often complicated because of complex interactions between parental traits and environmental conditions occurring during several stages of a reproductive event.Here,we used a simplified ecological situation-an amphibian species lacking post-oviposition parental care-and a laboratory approach to investigate the relationships between parental(both maternal and paternal)phenotypes(body size and condition)and reproductive success(fecundity,egg size,embryonic and larval duration,larval and metamorphic morphology).We found significant effects of maternal phenotype on fecundity,hatching success,and tadpole size,as well as on the duration of larval development.Interestingly,and more surprisingly,we also found a potential contribution of the paternal phenotype occurring during early(embryonic development duration)offspring development.Although our study focused on life-history traits such as body size and development duration,additional mechanisms involving physiological costs of development may well mediate the relationships between parental phenotypes and offspring development.Future studies are required to decipher the mechanisms underlying our findings in order to clarify the mechanistic basis of the links between parental phenotypes and offspring development.
基金Agence Nationale de la recherche(Grant no.ANR-20-CE02-0010).
文摘The vast diversity of morphologies,body size,and lifestyles of snakes represents an important source of information that can be used to derive bio-inspired robots through a biology-push and pull process.An understanding of the detailed kinematics of swimming snakes is a fundamental prerequisite to conceive and design bio-inspired aquatic snake robots.However,only limited information is available on the kinematics of swimming snake.Fast and accurate methods are needed to fill this knowledge gap.In the present paper,three existing methods were compared to test their capacity to characterize the kinematics of swimming snakes.(1)Marker tracking(Deftac),(2)Markerless pose estimation(DeepLabCut),and(3)Motion capture were considered.(4)We also designed and tested an automatic video processing method.All methods provided different albeit complementary data sets;they also involved different technical issues in terms of experimental conditions,snake manipulation,or processing resources.Marker tracking provided accurate data that can be used to calibrate other methods.Motion capture posed technical difficulties but can provide limited 3D data.Markerless pose estimation required deep learning(thus time)but was efficient to extract the data under various experimental conditions.Finally,automatic video processing was particularly efficient to extract a wide range of data useful for both biology and robotics but required a specific experimental setting.
文摘Bio-loggers are miniaturized autonomous devices that record quantitative data on the state of free-ranging ani-mals(e.g.behavior,position and physiology)and their natural environment.This is especially relevant for spe-cies where direct visual observation is difficult or impossible.Today,ongoing technical development allows the monitoring of numerous parameters in an increasing range of species over extended periods.However,the ex-ternal attachment of devices might affect various aspects of animal performance(energetics,thermoregulation,foraging as well as social and reproductive behavior),which ultimately affect fitness.External attachment might also increase entanglement risk and the conspicuousness of animals,leaving them more vulnerable to preda-tion.By contrast,implantation of devices can mitigate many of these undesirable effects and might be prefera-ble,especially for long-term studies,provided that the many challenges associated with surgical procedures can be mastered.Implantation may then allow us to gather data that would be impossible to obtain otherwise and thereby may provide new and ecologically relevant insights into the life of wild animals.Here,we:(i)discuss the pros and cons of attachment methods;(ii)highlight recent field studies that used implanted bio-loggers to address eco-physiological questions in a wide range of species;and(iii)discuss logger implantation in light of ethical considerations.
文摘Contrary to the nestling phase, the post-fledging phase has been less studied probably because it is challenging to follow the chicks after they fledge. However, this phase is crucial to consider when focusing on the life cycle of individuals because it is associated with new demands: After leaving the nest, individuals have to find their own food and cope with a new set of previously unknown stressors. In this study, we aimed at better understanding how energetically demanding the post-ftedging period is in house sparrows Passer domesticus by measuring several indices of a fledgling's state (body condition, fat and muscle scores and plumage quality). If the energetic demands of the post-fledging period are greater than those of the adult life, we predicted that fledglings should be in lower condition and should have a plumage of lower quality relative to adults. Supporting this prediction, the condition and the plumage of fledglings differed dramatically from those of adults. Interestingly, this difference disappeared in autumn. Overall, our results suggest that the post-fledging period is probably one of the most energetically demanding of the life cycle in this species. Supporting this idea, the resighting probability of fledglings was lower relative to adults. However, resighting probability depends on many factors (mortality, dispersal, habitat use and behaviours) and future studies are necessary to tease apart their relative importance in determining resighting probability [Current Zoology 60 (4): 449-459, 2014].
基金funded by the United States National Science Foundation (NSF) PEET grant DEB-0731510 ‘Monographic Studies in the Nectriaceae,Hypocreales:Nectria,Cosmospora,and Neonectria’ to P. Chaverri,A.Y. Rossman,and G.J. Samuels