Arnaud Béchet - Academia.edu (original) (raw)
Papers by Arnaud Béchet
by Frank Hailer, Abel Bernadou, Arnaud Béchet, Giorgio Bernardi, Tomaso Patarnello, Kuldeep K. Lal, Marcelo Oliva, Jonathan Sandoval-Castillo, Peter Teske, Carol A . Stepien, and Carol Stepien
Molecular ecology resources, 2009
This article documents the addition of 512 microsatellite marker loci and nine pairs of Single Nu... more This article documents the addition of 512 microsatellite marker loci and nine pairs of Single Nucleotide Polymorphism (SNP) sequencing primers to the Molecular Ecology Resources Database. Loci were developed for the following species: Alcippe morrisonia morrisonia, Bashania fangiana, Bashania fargesii, Chaetodon vagabundus, Colletes floralis, Coluber constrictor flaviventris, Coptotermes gestroi, Crotophaga major, Cyprinella lutrensis, Danaus plexippus, Fagus grandifolia, Falco tinnunculus, Fletcherimyia fletcheri, Hydrilla verticillata, Laterallus jamaicensis coturniculus, Leavenworthia alabamica, Marmosops incanus, Miichthys miiuy, Nasua nasua, Noturus exilis, Odontesthes bonariensis, Quadrula fragosa, Pinctada maxima, Pseudaletia separata, Pseudoperonospora cubensis, Podocarpus elatus, Portunus trituberculatus, Rhagoletis cerasi, Rhinella schneideri, Sarracenia alata, Skeletonema marinoi, Sminthurus viridis, Syngnathus abaster, Uroteuthis (Photololigo) chinensis, Verticillium da...
Only 15 cases of breeding of Ross's gull Rhodostethia rosea are known outside of Siberia. Whi... more Only 15 cases of breeding of Ross's gull Rhodostethia rosea are known outside of Siberia. While numerous birds are regularly seen in the fall at Point Barrow, Alaska, until now only one breeding locality has been known for Nunavut, Canada. We found a second breeding locality in Nunavut in the northwestern corner of Prince Charles Island (Foxe Basin). We observed
Ecology and Evolution, 2014
2008 IEEE International Conference on Acoustics, Speech and Signal Processing, 2008
Here we present a new approach to automatically detect and count breeding greater flamingos (Phoe... more Here we present a new approach to automatically detect and count breeding greater flamingos (Phoenicopterus Roseus) on aerial photographs of their colonies. We consider a stochastic approach based on object processes also called marked point processes. The objects represent flamingos which are defined as ellipses. We formulate a Gibbs density, associated with the marked point process of ellipses, which is
Ecology and Evolution, 2013
Accurate knowledge of the functional response of predators to prey density is essential for under... more Accurate knowledge of the functional response of predators to prey density is essential for understanding food web dynamics, to parameterize mechanistic models of animal responses to environmental change, and for designing appropriate conservation measures. Greater flamingos (Phoenicopterus roseus), a flagship species of Mediterranean wetlands, primarily feed on Artemias (Artemia spp.) in commercial salt pans, an industry which may collapse for economic reasons. Flamingos also feed on alternative prey such as Chironomid larvae (e.g., Chironomid spp.) and rice seeds (Oryza sativa). However, the profitability of these food items for flamingos remains unknown. We determined the functional responses of flamingos feeding on Artemias, Chironomids, or rice. Experiments were conducted on 11 captive flamingos. For each food item, we offered different ranges of food densities, up to 13 times natural abundance. Video footage allowed estimating intake rates. Contrary to theoretical predictions for filter feeders, intake rates did not increase linearly with increasing food density (type I). Intake rates rather increased asymptotically with increasing food density (type II) or followed a sigmoid shape (type III). Hence, flamingos were not able to ingest food in direct proportion to their abundance, possibly because of unique bill structure resulting in limited filtering capabilities. Overall, flamingos foraged more efficiently on Artemias. When feeding on Chironomids, birds had lower instantaneous rates of food discovery and required more time to extract food from the sediment and ingest it, than when filtering Artemias from the water column. However, feeding on rice was energetically more profitable for flamingos than feeding on Artemias or Chironomids, explaining their attraction for rice fields. Crucially, we found that food densities required for flamingos to reach asymptotic intake rates are rarely met under natural conditions. This allows us to predict an immediate negative effect of any decrease in prey density upon flamingo foraging performance.
Biological Reviews, 2014
Only a few studies have shown positive impacts of ecological compensation on species dynamics aff... more Only a few studies have shown positive impacts of ecological compensation on species dynamics affected by human activities. We argue that this is due to inappropriate methods used to forecast required compensation in environmental impact assessments. These assessments are mostly descriptive and only valid at limited spatial and temporal scales. However, habitat suitability models developed to predict the impacts of environmental changes on potential species' distributions should provide rigorous science-based tools for compensation planning. Here we describe the two main classes of predictive models: correlative models and individual-based mechanistic models. We show how these models can be used alone or synoptically to improve compensation planning. While correlative models are easier to implement, they tend to ignore underlying ecological processes and lack accuracy. On the contrary, individual-based mechanistic models can integrate biological interactions, dispersal ability and adaptation. Moreover, among mechanistic models, those considering animal energy balance are particularly efficient at predicting the impact of foraging habitat loss. However, mechanistic models require more field data compared to correlative models. Hence we present two approaches which combine both methods for compensation planning, especially in relation to the spatial scale considered. We show how the availability of biological databases and software enabling fast and accurate population projections could be advantageously used to assess ecological compensation requirement efficiently in environmental impact assessments.
Journal of Experimental Biology, 2014
Most studies analyzing the effects of global warming on wild populations focus on gradual tempera... more Most studies analyzing the effects of global warming on wild populations focus on gradual temperature changes, yet it is also important to understand the impact of extreme climatic events. Here we studied the effect of two cold spells (January 1985 and February 2012) on the energetics of greater flamingos (Phoenicopterus roseus) in the Camargue (southern France). To understand the cause of observed flamingo mass mortalities, we first assessed the energy stores of flamingos found dead in February 2012, and compared them with those found in other bird species exposed to cold spells and/or fasting. Second, we evaluated the monthly energy requirements of flamingos across 1980-2012 using the mechanistic model Niche Mapper TM . Our results show that the body lipids of flamingos found dead in 2012 corresponded to 2.6±0.3% of total body mass, which is close to results found in woodcocks (Scolopax rusticola) that died from starvation during a cold spell (1.7±0.1%), and much lower than in woodcocks which were fed throughout this same cold spell (13.0±2%). Further, Niche Mapper TM predicted that flamingo energy requirements were highest (+6-7%) during the 1985 and 2012 cold spells compared with 'normal' winters. This increase was primarily driven by cold air temperatures. Overall, our findings strongly suggest that flamingos starved to death during both cold spells. This study demonstrates the relevance of using mechanistic energetics modelling and body condition analyses to understand and predict the impact of extreme climatic events on animal energy balance and winter survival probabilities.
La conservation des espèces d'oiseaux d'eau coloniaux nécessite de connaître à la fois leur struc... more La conservation des espèces d'oiseaux d'eau coloniaux nécessite de connaître à la fois leur structure métapopulationnelle et les facteurs qui conditionnent leur succès reproducteur. Le Flamant rose, Phoenicopterus roseus, espèce emblématique de la conservation des zones humides, possède une large distribution géographique mais n'exploite qu'un nombre très limité de sites pour sa reproduction. Une meilleure connaissance du fonctionnement métapopulationnel de l'espèce et des causes de variation de son succès reproducteur représentent donc deux enjeu majeurs pour la conservation de l'espèce. L'objet de cette thèse est de contribuer efficacement aux mesures de gestion, d'une part en établissant le degré de connectivité existant entre les différents sous-ensembles populationnels décrits jusqu'à présent, et d'autre part en évaluant quantitativement la contribution de différents facteurs endogènes et exogènes au succès reproducteur.
Waterbirds, 2007
Adult Greater Flamingos ( Phoenicopterus roseus ) are sexually dimorphic, with males being on ave... more Adult Greater Flamingos ( Phoenicopterus roseus ) are sexually dimorphic, with males being on average larger and heavier than females. However, there is no practical way to sex the chicks by their morphology. Here we describe a method relying on quick and easy DNA extraction from feathers. A PCR test employing primers to amplify introns whose lengths usually differ between the CHD-W and the CHD-Z genes allow sex discrimination. This method is thus a fast, accurate and inexpensive protocol to sex flamingo chicks from feathers bulbs sampled in the field.
Schweizer Archiv für Tierheilkunde, 2013
Pododermatitis is a worldwide problem in captive flamingos. We performed an evaluation of differe... more Pododermatitis is a worldwide problem in captive flamingos. We performed an evaluation of different influence factors (age, sex, weight, origin, breeding status) and a comparison of foot lesions between several zoological institutions and the feet of free-ranging Greater flamingos (Phoenicopterus roseus). A scoring system was used to determine the prevalence and types of lesions and severity. Cracks and nodules developed as early as 3 months of age and papillomatous growths as early as 6 to 7 months of age in captivity. Nodules with ulceration occurred significantly more often in birds older than 31 years and heavier than 4 kg. The comparison of different institutions revealed that birds kept in enclosures with natural-floored water ponds had significantly less severe lesions than birds kept in concrete water ponds. None of the free-ranging flamingos, which live on a muddy underground, showed any lesion. This study demonstrates that flooring, weight and age are important in the onset and progression of pododermatitis in flamingos.
by Frank Hailer, Abel Bernadou, Arnaud Béchet, Giorgio Bernardi, Tomaso Patarnello, Kuldeep K. Lal, Marcelo Oliva, Jonathan Sandoval-Castillo, Peter Teske, Carol A . Stepien, and Carol Stepien
Molecular ecology resources, 2009
This article documents the addition of 512 microsatellite marker loci and nine pairs of Single Nu... more This article documents the addition of 512 microsatellite marker loci and nine pairs of Single Nucleotide Polymorphism (SNP) sequencing primers to the Molecular Ecology Resources Database. Loci were developed for the following species: Alcippe morrisonia morrisonia, Bashania fangiana, Bashania fargesii, Chaetodon vagabundus, Colletes floralis, Coluber constrictor flaviventris, Coptotermes gestroi, Crotophaga major, Cyprinella lutrensis, Danaus plexippus, Fagus grandifolia, Falco tinnunculus, Fletcherimyia fletcheri, Hydrilla verticillata, Laterallus jamaicensis coturniculus, Leavenworthia alabamica, Marmosops incanus, Miichthys miiuy, Nasua nasua, Noturus exilis, Odontesthes bonariensis, Quadrula fragosa, Pinctada maxima, Pseudaletia separata, Pseudoperonospora cubensis, Podocarpus elatus, Portunus trituberculatus, Rhagoletis cerasi, Rhinella schneideri, Sarracenia alata, Skeletonema marinoi, Sminthurus viridis, Syngnathus abaster, Uroteuthis (Photololigo) chinensis, Verticillium da...
Only 15 cases of breeding of Ross's gull Rhodostethia rosea are known outside of Siberia. Whi... more Only 15 cases of breeding of Ross's gull Rhodostethia rosea are known outside of Siberia. While numerous birds are regularly seen in the fall at Point Barrow, Alaska, until now only one breeding locality has been known for Nunavut, Canada. We found a second breeding locality in Nunavut in the northwestern corner of Prince Charles Island (Foxe Basin). We observed
Ecology and Evolution, 2014
2008 IEEE International Conference on Acoustics, Speech and Signal Processing, 2008
Here we present a new approach to automatically detect and count breeding greater flamingos (Phoe... more Here we present a new approach to automatically detect and count breeding greater flamingos (Phoenicopterus Roseus) on aerial photographs of their colonies. We consider a stochastic approach based on object processes also called marked point processes. The objects represent flamingos which are defined as ellipses. We formulate a Gibbs density, associated with the marked point process of ellipses, which is
Ecology and Evolution, 2013
Accurate knowledge of the functional response of predators to prey density is essential for under... more Accurate knowledge of the functional response of predators to prey density is essential for understanding food web dynamics, to parameterize mechanistic models of animal responses to environmental change, and for designing appropriate conservation measures. Greater flamingos (Phoenicopterus roseus), a flagship species of Mediterranean wetlands, primarily feed on Artemias (Artemia spp.) in commercial salt pans, an industry which may collapse for economic reasons. Flamingos also feed on alternative prey such as Chironomid larvae (e.g., Chironomid spp.) and rice seeds (Oryza sativa). However, the profitability of these food items for flamingos remains unknown. We determined the functional responses of flamingos feeding on Artemias, Chironomids, or rice. Experiments were conducted on 11 captive flamingos. For each food item, we offered different ranges of food densities, up to 13 times natural abundance. Video footage allowed estimating intake rates. Contrary to theoretical predictions for filter feeders, intake rates did not increase linearly with increasing food density (type I). Intake rates rather increased asymptotically with increasing food density (type II) or followed a sigmoid shape (type III). Hence, flamingos were not able to ingest food in direct proportion to their abundance, possibly because of unique bill structure resulting in limited filtering capabilities. Overall, flamingos foraged more efficiently on Artemias. When feeding on Chironomids, birds had lower instantaneous rates of food discovery and required more time to extract food from the sediment and ingest it, than when filtering Artemias from the water column. However, feeding on rice was energetically more profitable for flamingos than feeding on Artemias or Chironomids, explaining their attraction for rice fields. Crucially, we found that food densities required for flamingos to reach asymptotic intake rates are rarely met under natural conditions. This allows us to predict an immediate negative effect of any decrease in prey density upon flamingo foraging performance.
Biological Reviews, 2014
Only a few studies have shown positive impacts of ecological compensation on species dynamics aff... more Only a few studies have shown positive impacts of ecological compensation on species dynamics affected by human activities. We argue that this is due to inappropriate methods used to forecast required compensation in environmental impact assessments. These assessments are mostly descriptive and only valid at limited spatial and temporal scales. However, habitat suitability models developed to predict the impacts of environmental changes on potential species' distributions should provide rigorous science-based tools for compensation planning. Here we describe the two main classes of predictive models: correlative models and individual-based mechanistic models. We show how these models can be used alone or synoptically to improve compensation planning. While correlative models are easier to implement, they tend to ignore underlying ecological processes and lack accuracy. On the contrary, individual-based mechanistic models can integrate biological interactions, dispersal ability and adaptation. Moreover, among mechanistic models, those considering animal energy balance are particularly efficient at predicting the impact of foraging habitat loss. However, mechanistic models require more field data compared to correlative models. Hence we present two approaches which combine both methods for compensation planning, especially in relation to the spatial scale considered. We show how the availability of biological databases and software enabling fast and accurate population projections could be advantageously used to assess ecological compensation requirement efficiently in environmental impact assessments.
Journal of Experimental Biology, 2014
Most studies analyzing the effects of global warming on wild populations focus on gradual tempera... more Most studies analyzing the effects of global warming on wild populations focus on gradual temperature changes, yet it is also important to understand the impact of extreme climatic events. Here we studied the effect of two cold spells (January 1985 and February 2012) on the energetics of greater flamingos (Phoenicopterus roseus) in the Camargue (southern France). To understand the cause of observed flamingo mass mortalities, we first assessed the energy stores of flamingos found dead in February 2012, and compared them with those found in other bird species exposed to cold spells and/or fasting. Second, we evaluated the monthly energy requirements of flamingos across 1980-2012 using the mechanistic model Niche Mapper TM . Our results show that the body lipids of flamingos found dead in 2012 corresponded to 2.6±0.3% of total body mass, which is close to results found in woodcocks (Scolopax rusticola) that died from starvation during a cold spell (1.7±0.1%), and much lower than in woodcocks which were fed throughout this same cold spell (13.0±2%). Further, Niche Mapper TM predicted that flamingo energy requirements were highest (+6-7%) during the 1985 and 2012 cold spells compared with 'normal' winters. This increase was primarily driven by cold air temperatures. Overall, our findings strongly suggest that flamingos starved to death during both cold spells. This study demonstrates the relevance of using mechanistic energetics modelling and body condition analyses to understand and predict the impact of extreme climatic events on animal energy balance and winter survival probabilities.
La conservation des espèces d'oiseaux d'eau coloniaux nécessite de connaître à la fois leur struc... more La conservation des espèces d'oiseaux d'eau coloniaux nécessite de connaître à la fois leur structure métapopulationnelle et les facteurs qui conditionnent leur succès reproducteur. Le Flamant rose, Phoenicopterus roseus, espèce emblématique de la conservation des zones humides, possède une large distribution géographique mais n'exploite qu'un nombre très limité de sites pour sa reproduction. Une meilleure connaissance du fonctionnement métapopulationnel de l'espèce et des causes de variation de son succès reproducteur représentent donc deux enjeu majeurs pour la conservation de l'espèce. L'objet de cette thèse est de contribuer efficacement aux mesures de gestion, d'une part en établissant le degré de connectivité existant entre les différents sous-ensembles populationnels décrits jusqu'à présent, et d'autre part en évaluant quantitativement la contribution de différents facteurs endogènes et exogènes au succès reproducteur.
Waterbirds, 2007
Adult Greater Flamingos ( Phoenicopterus roseus ) are sexually dimorphic, with males being on ave... more Adult Greater Flamingos ( Phoenicopterus roseus ) are sexually dimorphic, with males being on average larger and heavier than females. However, there is no practical way to sex the chicks by their morphology. Here we describe a method relying on quick and easy DNA extraction from feathers. A PCR test employing primers to amplify introns whose lengths usually differ between the CHD-W and the CHD-Z genes allow sex discrimination. This method is thus a fast, accurate and inexpensive protocol to sex flamingo chicks from feathers bulbs sampled in the field.
Schweizer Archiv für Tierheilkunde, 2013
Pododermatitis is a worldwide problem in captive flamingos. We performed an evaluation of differe... more Pododermatitis is a worldwide problem in captive flamingos. We performed an evaluation of different influence factors (age, sex, weight, origin, breeding status) and a comparison of foot lesions between several zoological institutions and the feet of free-ranging Greater flamingos (Phoenicopterus roseus). A scoring system was used to determine the prevalence and types of lesions and severity. Cracks and nodules developed as early as 3 months of age and papillomatous growths as early as 6 to 7 months of age in captivity. Nodules with ulceration occurred significantly more often in birds older than 31 years and heavier than 4 kg. The comparison of different institutions revealed that birds kept in enclosures with natural-floored water ponds had significantly less severe lesions than birds kept in concrete water ponds. None of the free-ranging flamingos, which live on a muddy underground, showed any lesion. This study demonstrates that flooring, weight and age are important in the onset and progression of pododermatitis in flamingos.