|Les articles de Jocelyn Champagnon||https://tourduvalat.centredoc.fr/rss.php?id=32|
Les articles de Jocelyn Champagnon
de Simone Santoro, Jocelyn Champagnon, Sergey P Kharitonov, Leo Zwarts, H Dieter, Manuel Manez, Boudjema Samraoui, Riad Nedjah, Stefano Volponi, Santiago Cano-Alonso
In SIS Conservation, 1 (December, 2019), 139-146
En ligne : storkibisspoonbill.org[...]
The Glossy Ibis is among the most widespread bird species in the world. However, the Glossy Ibis erratic occurrence and distribution makes it a difficult species to study, and we know little about its dispersal and metapopulation dynamics. This study summarises previously-scattered and unpublished information by collating, in a single database, the largest number of longdistance recoveries ever reached for this species (190 individuals). Our findings suggest that (i) according to old records (about 1910 - 1995) the dispersal from the breeding grounds in East Europe was directed towards the Sahelian floodplains, North-East Africa, the Middle East and India; (ii) West and East Europe populations are probably connected; (iii) the recently (about 1995 onwards) increasing and spreading populations in West Europe do not tend to migrate south and overwinter in Sub-Saharan Africa; and, (iv) the genetic distance between geographically distant populations might be low considering the records of long-distance flights with the most impressive, and unpublished, one being that of an individual moving from Spain to the Virgin Islands (> 6,000 Km). Overall, these findings highlight the need for a research network capable of dealing with the frequent changes in the distribution and dispersal dynamics of the Glossy Ibis and its fast responses to environmental changes.
de Jocelyn Champagnon, Yves Kayser, Jérémiah Petit, Loïc Marion, Sebastien Reeber, Thomas Blanchon, Samuel Hilaire, Irene Badone, Pierre Crouzier, Regis Purenne, et al.
In SIS Conservation, 1 (December, 2019), 50-55
En ligne : storkibisspoonbill.org[...]
The Glossy Ibis Plegadis falcinellus was very rarely breeding in France until its settlement in Camargue in 2006, in a colony of ardeids. From then, the number of breeding pairs increased exponentially to reach 2,087 breeding pairs in 2017 distributed over ten colonies mainly in Camargue but also in others sites over the French Mediterranean coast. In parallel, breeding attempts occurred regularly in other regions, with some successes in Loire Atlantic on the Atlantic coast. Here we present some preliminary results on the ringing programme of chicks conducted in Camargue since 2006 and on the diet of the breeding birds. Finally, we discuss factors that influence the settlement of new colonies.
de Jocelyn Champagnon, Hugo Carré, Lisa Gili
In PeerJ, 7 (October, 2019), e7844
En ligne : peerj.com[...]
Background Long-term research is crucial for the conservation and development of knowledge in ecology; however, it is essential to quantify and minimize any negative effects associated with research to gather reliable and representative long-term monitoring data. In colonial bird species, chicks are often marked with coded bands in order to assess demographic parameters of the population. Banding chicks in multi-species colonies is challenging because it involves disturbances to species that are at different stages of progress in their reproduction. Methods We took advantage of a long term banding program launched on Glossy Ibis (Plegadis falcinellus) breeding in a major mixed colony of herons in Camargue, southern France, to assess the effect of banding operation disturbance on the reproductive success of the three most numerous waterbirds species in the colony. Over two breeding seasons (2015 and 2016), 336 nests of Glossy Ibis, Little Egrets (Egretta garzetta) and Cattle Egrets (Bubulcus ibis) were monitored from a floating blind in two zones of the colony: one zone disturbed twice a year by the banding activities and another not disturbed (control zone). We applied a logistic-exposure analysis method to estimate the daily survival rate (DSR) of nests and chicks aged up to three weeks. Results Daily survival rate of Glossy Ibis was reduced in the disturbed zone while DSR increased for Little and Cattle Egrets in the disturbed zone. Nevertheless, DSR was not reduced on the week following the banding, thus discarding a direct effect of handling on breeding success of Glossy Ibis. The protocol and statistical analysis presented here are robust and can be applied to any bird species to test for the effect of a research disturbance or other short and repeated temporal events that may affect reproductive success over one or more breeding seasons.
de Luis Zambrano, Jocelyn Champagnon
In Zones Humides Infos, 97-98 (Eté 2019), 7
de Benjamin Folliot, Matthieu Guillemain, Jocelyn Champagnon, Alain Caizergues
In Faune sauvage, 322 (2019), 19-24
En ligne : www.researchgate.net[...]
Afin de comprendre l'origine du déclin des populations de Fuligule milouin constaté en Europe de l'Ouest, l'Office national de la chasse et de la faune sauvage réalise des recherches sur cette espèce depuis le début des années 2000. Le présent article, qui s'inscrit dans cette problèmatique, résume les travaux d'une thèse soutenue en décembre 2018 dont les principaux objectifs ont été d'appréhender le fonctionnement des populations de cet anatidé afin de cerner les causes possibles de son déclin.
de David Vallecillo, Pierre Defos du Rau, Anthony Olivier, Jocelyn Champagnon, Matthieu Guillemain, Nicolas Croce, Gregoire Massez, Jérémiah Petit, Nicolas Beck, Jean-Yves Mondain-monval
In Faune sauvage, 323 (Avril-Juin, 2019), 33-39
En Camargue, plusieurs groupes de chasseurs ont expérimenté des changements dans leurs modalités de gestion des habitats et des prélèvements, dans l'objectif de pratiquer une activité cynégétique à la fois plus durable et plus favorable à la biodiversité. Quelques exemples de ces différentes pratiques mises en oeuvre sur cinq territoires sont présentés dans cet article.
de Julien Renet, Lisa Leprêtre, Jocelyn Champagnon, Philippe Lambret
In Herpetological Journal (The), 29(1) (January, 2019), 13-22
En ligne : www.thebhs.org[...]
The estimation of demographic parameters in wild populations is strengthened by individual identification. For amphibians, various techniques are used to either temporarily or permanently mark individuals for identification. Photo-identification of body patterns offers a non-invasive technique. However, the reliability of photo-recognition software is key to the reliable estimation of the true demographic parameters. In the current study, we assessed the effectiveness of fully-automated and semi-automated software: Wild-ID and APHIS. We used the cryptic salamander Hydromantes strinatii as our study species. We used the False Rejection Rate (FRR) of Top 1, Top 5 and Top 10 matches of chest and cloaca pictures. Finally, we assessed the bias induced by our FRR for the estimation of population size through simulation.
de Jocelyn Champagnon, Jérémiah Petit, Yves Kayser
In Journal of Heron Biology and Conservation, 3(5) (2018), 13-14
En ligne : www.heronconservation.org[...]
de Benjamin Folliot, Matthieu Guillemain, Jocelyn Champagnon, Alain Caizergues
In Wildlife Biology, 144 (10/2018), wlb.00427
En ligne : www.bioone.org[...]
We used ringed-recoveries to assess: 1) the connectivity (movements of individuals) between the three putative flyways (north–west Europe, central Europe, south–west Asia) of common pochards in the Western Palearctic, 2) possible spatio-temporal variations in the distribution of the species, and, 3) temporal evolution in spring and autumn migration dates. Based on winter counts of common pochards in the north–west European flyway, we distinguished three periods in the analyses (1960–1990, 1991–2000 and 2001–2016), which correspond to successive periods of population increase, peak and decline, respectively. Whatever the season (wintering or breeding) and period of ringing, large probabilities of ring-recoveries outside the flyway of origin (ringing) were recorded, suggesting a high connectivity between the three putative flyways. There was a significant trend towards an earlier departure from the wintering area, and an eastward shift of spring recoveries over periods. In contrast, neither autumn/winter recovery locations, nor departure dates from the breeding area in Latvia and Russia changed over periods. The latter results do not support the hypothesis that short-stopping (i.e. a reduction of fall migration distances/delaying of departure dates from the breeding area) could explain the observed decline of wintering common pochards in the north–west European flyway. Indirect recoveries support that large proportions of individuals wintering in western Europe may originate from the south–west Asia flyway and more particularly from a region in Siberia located in the Ob river catchment area. Considering trends in numbers for the three flyways together confirmed the “vulnerable” IUCN status of common pochard in the Western Palearctic as a whole, with a 35% decline over the last decade. The important connectivity between the northwest, central European and southwest Asian flyways call for considering such conservation problems at a much broader scale than the regional flyway. /
Le fuligule milouin, canard plongeur qualifié de migrateur partiel, accuse depuis les années 2000 un déclin préoccupant des population hivernantes européennes ayant mené à la réévaluation de son statut de protection. Depuis 2015, cette espèce est dorénavant considérée comme vulnérable selon l’IUCN. Une diminution de son succès de reproduction en Europe de l’Est a été évoquée, selon les dires d’expert européens, comme responsable de ce déclin. Dans cet article nous avons cherché à déterminer si la diminution récente (observée principalement grâce aux comptages en hiver en Europe de l’Ouest) n’est pas la conséquence de changements qui ont lieu au-delà de la voie de migration d’Europe de l’Ouest. Pour cela, nous avons utilisé les données de baguage-reprise depuis 1960.
Nos résultats montrent qu’effectivement de nombreux échanges ont lieu entre les voies de migration classiquement délimitées, et en particulier avec la voie de migration sud-ouest asiatique. Nous avons ainsi déterminé une très forte connectivité des milouins bagués en Europe de l’Ouest avec une importante aire de reproduction (~ 500 000 km²) située à l’Est de l’Oural, à la frontière entre la Russie et le Kazakhstan. La littérature récente atteste que cette aire de reproduction a subi une forte dégradation de son habitat notamment par l'assèchement des zones humides pour la culture de coton et l’intensification de l’exploitation de gaz et de pétrole entraînant une pollution des eaux et des habitats. Ainsi, le déclin des populations hivernantes observé en Europe pourrait provenir d’une diminution du succès de reproduction à la fois en Europe de l’Est mais également en Russie, ce qui n’était pas envisagée auparavant. L’état de la population hivernante dans la voie de migration sud-ouest asiatique reste inconnu (trop forte incertitude autour de la tendance moyenne des effectifs hivernants). Nous suggérons ainsi la nécessité de prendre sérieusement en compte cette voie de migration dans les objectifs de gestion du fuligule milouin, ce qui passe par l’amélioration de nos connaissances en Russie.
de Jocelyn Champagnon, Lebreton Jean‐Dominique, Drummond Hugh, Anderson David J.
In Ecology, 99(5) (May 1, 2018), 1063-1072
En ligne : esajournals.onlinelibrary.wiley.com[...]
Understanding and modeling population change is urgently needed to predict effects of climate change on biodiversity. High trophic?level organisms are influenced by fluctuations of prey quality and abundance, which themselves may depend on climate oscillations. Modeling effects of such fluctuations is challenging because prey populations may vary with multiple climate oscillations occurring at different time scales. The analysis of a 28 yr time series of capture-recapture data of a tropical seabird, the Nazca Booby (Sula granti), in the Galápagos, Ecuador, allowed us to test for demographic effects of two major ocean oscillations occurring at distinct time-scales: the inter-annual El Niño Southern Oscillation (ENSO) and inter-decadal oscillations. As expected for a tropical seabird, survival of fledgling birds was highly affected by extreme ENSO events; by contrast, neither recruitment nor breeding participation were affected by either ENSO or decadal oscillations. More interesting, adult survival, a demographic trait that canalizes response to environmental variations, was unaffected by inter-annual ENSO oscillations yet was shaped by the Pacific Decadal Oscillation and small pelagic fish regime. Adult survival decreased during oceanic conditions associated with higher breeding success, an association probably mediated in this species by costs of reproduction that reduce survival when breeding attempts end later. To our knowledge, this is the first study suggesting that survival of a vertebrate can be vulnerable to a natural multidecadal oscillation. / Dans cette étude, des chercheurs ont évalué l'effet d'El Niño et de l'ODP sur la survie d'un oiseau marin tropical, le Fou de Nazca, qui niche aux îles Galapagos et dont l'espérance de vie est d'environ 15 ans. Cet oiseau est un bon modèle d'étude de l'impact du changement climatique sur les oiseaux car il consomme des ressources directement affectées (les sardines notamment) par les variations du climat. A partir du suivi à long terme des baguages de cette espèce (1984-2012), les scientifiques ont mis en évidence que la survie des jeunes Fous de Nazca est très faible lors d'événements El Niño car ces périodes sont marquées par une faible quantité de poissons (en particulier les sardines, l'aliment de prédilection de ces oiseaux). La survie des spécimens adultes est quant à elle affectée par l'ODP. Les chercheurs ont observé une mortalité plus importante lors des phases chaudes de ce cycle qui sont pourtant propices à la prolifération de sardines et offrent donc un accès privilégié à la nourriture. Cette surprenante corrélation pourrait s'expliquer par un coût de reproduction plus important : les adultes perdraient plus d'énergie dans la reproduction (moins d'abandon du nid) au détriment de leur propre survie. À l'inverse, lors de phases froides telles que celle en place depuis 2008, la survie des adultes est meilleure car la mortalité des petits et l'abandon du nid leur permettent de récupérer plus rapidement.
Ce travail constitue une avancée majeure pour la compréhension des effets du climat sur les oiseaux marins. Il démontre pour la première fois l'impact d'une variation climatique à long cycle (ODP) sur la survie d'une espèce et pourrait par la suite s'étendre à d'autres espèces d'oiseaux marins afin de prédire les effets du changement climatique sur ces espèces.
de Yves Kayser, Michel Gauthier-Clerc, Thomas Blanchon, Philippe Vandewalle, Silke Befeld, Jérémiah Petit, Rémi Tiné, Amine Flitti, Jocelyn Champagnon
In Ornithos, 25(1) (2018), 4-13
The Common Crane was a rare wintering bird in The Camargue until the late 1990s and early 2000s. From the winter of 2003- 2004, wintering numbers have steadily increased to more than 14,000 individuals by January 2017, spread over a dozen roosts. The frequented roosts are large open areas, usually made up of freshwater marshes. During the winter season, cranes mainly feed on rice stubble. Other food resources such as winter wheat are used to a lesser extent. Some birds do not hesitate to fly further up to 30 km to fetch food. Fifty ringed birds were controlled between 2013 and 2017, the majority (89 %) of them originated from Finland. It seems that the cranes use two migration routes to The Camargue : one central European routeway and another one possibly passing through western France, which could indicate a loop migration.
de P. Söderquist, J. Elmberg, G. Gunnarsson, C.-G. Thulin, Jocelyn Champagnon, Matthieu Guillemain, J. Kreisinger, H. H. T. Prins, R. P. M. A. Crooijmans, R. H. S. Kraus
In European Journal of Wildlife Research, 63(6) (12/2017), 1-13
En ligne : link.springer.com[...]
Disruption of naturally evolved spatial patterns of genetic variation and local adaptations is a growing concern in wildlife management and conservation. During the last decade, releases of native taxa with potentially non-native genotypes have received increased attention. This has mostly concerned conservation programs, but releases are also widely carried out to boost harvest opportunities. The mallard, Anas platyrhynchos, is one of few terrestrial migratory vertebrates subjected to large-scale releases for hunting purposes. It is the most numerous and widespread duck in the world, yet each year more than three million farmed mallard ducklings are released into the wild in the European Union alone to increase the harvestable population. This study aimed to determine the genetic effects of such large-scale releases of a native species, specifically if wild and released farmed mallards differ genetically among subpopulations in Europe, if there are signs of admixture between the two groups, if the genetic structure of the wild mallard population has changed since large-scale releases began in the 1970s, and if the current data matches global patterns across the Northern hemisphere. We used Bayesian clustering (Structure software) and Discriminant Analysis of Principal Components (DAPC) to analyze the genetic structure of historical and present-day wild (n = 171 and n = 209, respectively) as well as farmed (n = 211) mallards from six European countries as inferred by 360 single-nucleotide polymorphisms (SNPs). Both methods showed a clear genetic differentiation between wild and farmed mallards. Admixed individuals were found in the present-day wild population, implicating introgression of farmed genotypes into wild mallards despite low survival among released farmed mallards. Such cryptic introgression would alter the genetic composition of wild populations and may have unknown long-term consequences for conservation.
de Matthieu Guillemain, Clément Calenge, Jocelyn Champagnon, Richard Hearn
In Journal of Avian Biology, 48(10) (10/2017), 1331-1341
En ligne : doi.wiley.com[...]
Accurate flyway delineation is a prerequisite for effective conservation and management of migratory bird populations, yet such limits have so far mostly been set subjectively. We present a statistical method to infer population boundaries from the analysis of ring recoveries, using a Bayesian framework. The approach was applied to Eurasian teal Anas crecca ringed in Camargue, southern France, and Abberton Reservoir, Essex, eastern England. The results presented show the boundaries of the two teal flyways in western Europe, with a zone of overlap, broadly matching those previously defined. The percentage of teal switching flyways (abmigration rate) was 2.4-2.6%, greater in birds ringed as juveniles than as adults. Abmigrants ended up at sites within the other flyway where the density of local birds was lower than expected by chance, suggesting abmigration resulted from exploratory or aberrant behaviour. The methodology presented here can be used to infer flyway boundaries of any bird with an adequate ring-re-encounter dataset, which has crucial consequences for the evaluation of their trends in abundance and hence conservation status, and the management of sustainable harvests.
de Thomas Blanchon, Jocelyn Champagnon, Yves Kayser, Lina López-Ricaurte, Paul Isenmann
In Alauda, 85(3) (oct 2017), 231-233
de Matthieu Guillemain, Jocelyn Champagnon, Marie-Lucile Gourlay-Larour, Francois Cavallo, Anne-Laure Brochet, Jean Hars, Gregoire Massez, Thierry George, Pierre-Yves Perroi, Veronique Jestin, et al.
In Ibis, 158(4) (October 2016), 743-753
En ligne : onlinelibrary.wiley.com[...]
Concerns about the spread of avian influenza viruses (AIVs) have led to cloacal swab sampling of hundreds of thousands of birds worldwide as part of AIV surveillance schemes, but the effects of cloacal swabbing have not been adequately evaluated. We tested for differences between swabbed, swabbed and bled, and non-sampled wild ducks in terms of live re-encounter and dead recoveries for Common Pochard Aythya ferina and Tufted Duck Aythya fuligula, and also determined re-encounter and recovery rates for Mallard Anas platyrhynchos and Common Teal Anas crecca. No effects of sampling methods were detected, except in Teal. Re-encounter rates were lower in sampled Teal than in controls, with annual re-encounter probabilities being 25% and 35% lower in males and females, respectively. Teal possibly left or avoided sampling sites, or sought sites where they were less detectable after sampling. In general, no deleterious effects were found, suggesting that cloacal swabbing and blood sampling are suitable methods for conducting AIV surveillance in ducks.
de Jocelyn Champagnon, Pierre Legagneux, Guillaume Souchay, Pablo Inchausti, Vincent Bretagnolle, François Bourguemestre, Laura Van Ingen, Matthieu Guillemain
In Ibis, 158(2) (April 2016), 1-10
En ligne : doi.wiley.com[...]
The survival of captive-bred individuals from release into the wild to their first breeding season is crucial to assess the success of reintroduction or translocation programmes, and to assess their potential impact of wild populations. However, assessing the survival of captive-bred individuals following their release is often complicated by immediate dispersal once in the wild. Here, we apply Lindberg's robust design model, a method that incorporates emigration from the study site, to obtain true estimates of survival of captive-bred Mallards Anas platyrhynchos, a common duck species released on a large scale in Europe since the 1970s. Overall survival rate from release in July until the onset of the next breeding season in April was low (0.18 ± 0.07 se) and equivalent to half the first-year survival of local wild Mallards. Higher overall detectability and temporary emigration during the hunting period revealed movements in response to hunting pressure. Such low survival of released Mallards during their first year may help prevent large-scale genetic mixing with the wild population. Nevertheless, by combining our results with regional waterfowl counts, we estimated that a minimum of 34% of the Mallards in the region were of captive origin at the onset of the breeding season. Although most released birds quickly die, restocking for hunting may be of sufficient magnitude to affect the wild population through genetic homogenization or loss of local adaptation. Robust design protocols allow for the estimation of true survival estimates by controlling for permanent and temporary emigration and may require only a moderate increase in fieldwork effort.
de Jocelyn Champagnon, Matthieu Guillemain, Jean-Yves Mondain-monval, Guillaume Souchay, Pierre Legagneux, Vincent Bretagnolle, Laura Van Ingen, François Bourguemestre, Jean-Dominique Lebreton
In Ornis Fennica, 93(1) (March 2016), 3-11
En ligne : www.ornisfennica.org
The consequences of releasing captive-bred game animals into the wild have received little attention, despite their potential demographic impact, as well as costs and/or benefits for recipient populations.If restockin gaims at increasing harvest opportunities,increased hunting pressure is expected,which would then be supported by either wild or released individuals.On the otherhand,the wild recipient population may benefit from there lease of captive-bred conspecifics if this reduces hunting pressure on the former through dilution of risk or selective harvesting of captive-bred individuals. Here, we modelled a Mallard (Anasplatyrhynchos)population consisting of wild individuals supplemented by captive-bred conspecifics,a very common practice in Europe over the last 40years.The objective was to test the effect of an increase of harvest rate on released and wild individuals, respectively. Our results show that, due to the low reproductive value of the released Mallards,the population was hardly affected by a change in harvest of these low performance individuals.
de Matthieu Guillemain, Jocelyn Champagnon, Gregoire Massez, Claire Agnès Pernollet, Thierry George, Andre Momerency, Géraldine Simon
In Wildfowl, 65 (2015), 51-63
Earlier studies from central and northern Europe have found a shortening of the ring recovery distance in Mallard Anas platyrhynchos, which was generally attributed to climate change leading to a northwards shift of the wintering range. Here we show that recovery distances for Mallard ringed during winter in the Camargue (southern France), at the southern end of their range, have also shortened over the last 50 years, from a mean of 417 km (se. +/- 17.4) for birds ringed between 1950-1978 to 74 km (+/- 28.9) for birds ringed between 2002-2013. In contrast to the studies in other areas, however, the more recent recoveries of Mallard ringed in the Camargue were made to the south and west of where they were previously, and changes in ring recoveries were likely caused by a greater proportion of sedentary birds among the Camargue wintering population. Discarding unlikely methodological biases that may explain the pattern observed, we suggest three non-mutually exclusive hypotheses to explain such a change: a) increased attractiveness of Camargue habitats as a winter quarter, with migrant birds now staying for longer periods and allowing more local recoveries, b) hybridization between resident captive-bred and wild Mallards, and 0 former migrants from northern Europe now foregoing long migration to this distant winter quarter due to climate change. Future studies combining genetic and isotope analyses may help in teasing these hypotheses apart, to provide a better understanding of the factors leading to such increased sedentarity.
de Matthieu Guillemain, Francois Cavallo, Gregoire Massez, Thierry George, Jean-Pierre Baudet, Pierre Gonzalez, Valerie Ducasse, Emmanuel Caillot, Benoit Lecaplain, Luc Tison, et al.
In Wildfowl, 65 (2015), 64-74
En ligne : wildfowl.wwt.org.uk[...]
Studies of waterbirds rely to a large extent on ringing and resighting or recapture data, whilst assuming that ringed birds are broadly representative of the population as a whole. This may not be the case if the capture process may in itself have an influence on the birds. The analyses presented here showed that the body mass of ringed ducks often decreases between capture and recapture if the latter occurs within a few days or weeks. This could possibly reflect stress caused by handling, which would be problematic if it causes ringed birds to behave in a way that differs from the population as a whole. Alternatively, body mass measurements could also be biased by the general use of bait to attract birds to the trap. Initial and subsequent body mass data recorded for Eurasian Teal Anas crecca caught then recaptured within three weeks were compared between sites where the birds were attracted to traps with bait or with live decoys. When bait was used individuals had a greater body mass at ringing but were lighter at recapture at all but one site, where only a marginal difference was found. Conversely, when using live decoys, body mass remained constant at the next capture event. This suggests that mass loss commonly observed between capture and recapture is not caused by handling, but is potentially an artefact linked to duck hyperphagia in the presence of abundant food at ringing. It also implies that most available duck body mass data, which are usually obtained from birds ringed at baited traps, may be artificially inflated. The present results are based on one single unbaited site, however, and experimental manipulative studies (alternating the use of bait and live decoys to trap birds) are needed to confirm the findings.
de Matthieu Guillemain, Claire Agnès Pernollet, Gregoire Massez, F. Cavallo, G. Simon, Jocelyn Champagnon
A large body of research has accumulated on the impact of climate change on wildlife movements and distributions, especially for migratory birds. We used large ringing datasets for the Common Teal (Anas crecca) from the Camargue, southern France, to compare historic (from 1956-1975) spatiotemporal patterns of teal recovery with those seen in modern (2002-2012) years and assess whether the migration phenology of these ringed birds and their use of the Camargue as winter quarters has changed. Because teal are short-distance migrants (i.e., they breed in northern Europe and winter north of the Sahara), they would be predicted to delay their autumn migration in response to climate change. Conversely, ring recoveries showed that teal are now arriving much earlier: a stable 80 % of the recoveries were made locally in the Camargue each week between mid-November and late January in the modern dataset, whereas this percentage was only 53 % on average in the older data, and the proportion of recoveries made locally in the Camargue gradually increased through the autumn and winter until late January. This suggests that Camargue habitats have changed markedly and become more attractive to teal compared to other potential wintering areas, consistent with known changes in local habitat management practices and improvements in the body condition of the birds. Despite the fact that global climate change will likely be one of the main drivers of wildlife distribution over the long term and at large spatial scales, local habitat management should not be overlooked, as it can increase habitat attractivity to migratory birds.
de Jocelyn Champagnon, P.-A. Crochet, J. Kreisinger, D. Cizkova, Michel Gauthier-Clerc, Gregoire Massez, P. Söderquist, T. Albrecht, Matthieu Guillemain
In Animal Conservation, 16(3) (JUN 2013), 295-305
Captive-bred mallards Anas platyrhynchos have been released for hunting purposes at a very large scale in Europe since the mid-1970s. In spite of a potential genetic impact, the actual contribution of restocked mallards to the genome of the target population has received little attention. The genetic structure of modern wild mallards in the Camargue, Southern France, was assessed from two samples: one originating from shot birds in hunting bags and one from presumed wild ducks captured alive in a hunting-free reserve. Reference samples originated from five mallard farms, as well as from museum samples collected before the mid-1970s (i.e. before massive mallard releases started). Our results revealed that the genetic signature of wild wintering mallards has not changed significantly because museum and presumed wild samples from the Camargue hunting-free nature reserve were genetically similar, and clearly differentiated from the farm mallards. This suggests that mallard releases in the Camargue or elsewhere in France, although massive, have not actually translated into complete admixture of wild and captive genomes, most likely due to low survival of released birds once in the wild. Nevertheless, although genetic introgression of the wild population by captive-bred was contained, we found significant rates of hybridization between wild and captive-bred mallards in modern samples. This result suggests that long-term releases of captive-bred mallards, if carried on at such large scale, could compromise irreversibly the genetic structure and composition of European mallards. This work contributes to fill in the gap on the monitoring of the genetic consequences of large-scale game releases for exploitation.
de Jocelyn Champagnon, Michel Gauthier-Clerc, J. D. Lebreton, Jean-Baptiste Mouronval, Matthieu Guillemain
In Faune sauvage, 298 (2013), 4-9
de Dagmar Cizkova, Veronika Javurkova, Jocelyn Champagnon, Jakub Kreisinger
In Biological Conservation, 152 (AUG 2012), 231-240
The genetic integrity of natural populations can be threatened through large-scale introduction of farmed stocks with different genetic or geographic origin. Huge numbers of farm-reared mallard (Anas platyrhynchos, Anatidae) have been introduced into the wild in many European countries since 1970. Czech breeding facilities currently produce around 200-300,000 ducks annually, exceeding wild numbers by around 10 times. Such facilities, however, were founded with hybrid ducks from outside the Czech Republic. Three types of DNA markers, two neutral (14 microsatellite DNA loci and the mitochondrial DNA control region) and one under selection (MHC class I locus), were used to genotype mallards from six Czech breeding facilities (n = 131) and seven wild nesting localities (n = 139). We found marked genetic divergence between wild and captive-bred populations, the latter having significantly lower genetic diversity. Released captive-bred mallards were integrated into breeding wild population through hybridization mediated by high frequency nesting. Overall, our data suggest that release of captive-bred individuals threatens the genetic integrity of wild population. Massive restocking may also be undesirable as regards public health. Waterfowl are known reservoirs of transmittable pathogens and large-scale restocking could alter immune defence gene frequencies in wild population. We propose the establishment of a national genetic monitoring programme for breeding facilities. (c) 2012 Published by Elsevier Ltd.
de Jocelyn Champagnon, J. Elmberg, Matthieu Guillemain, Michel Gauthier-Clerc, J.D. Lebreton
de Jocelyn Champagnon, Matthieu Guillemain, J. Elmberg, Gregoire Massez, F. Cavallo, Michel Gauthier-Clerc
de Marion Vittecoq, V. Grandhomme, Jocelyn Champagnon, Matthieu Guillemain, B. Crescenzo-chaigne, F. Renaud, F. Thomas, Michel Gauthier-Clerc, S. Van Der Werf
de Jocelyn Champagnon
En ligne : www.biu-montpellier.fr[...]
Le renforcement des populations naturelles exploitées par des individus captifs est rarement évalué, bien qu'il puisse induire des modifications notables sur la population naturelle à de nombreux niveaux : démographie, comportement, morphologie, génétique, pathogènes. Ce travail de thèse concerne les introductions de canards colverts Anas platyrhynchos réalisées à des fins cynégétiques. Cette pratique est très répandue en Europe, depuis plus de trente ans. Du fait de leur domestication en élevage, les canards lâchés subissent une mortalité naturelle très forte comparée aux oiseaux sauvages, à laquelle s'ajoute une plus grande vulnérabilité à la chasse. Une différenciation génétique marquée permet de discriminer les oiseaux lâchés de leurs congénères sauvages. Des croisements entre les deux groupes sont détectés, mais l'introgression reste limitée. Globalement, la contribution démographique et génétique des individus d'élevage à la population sauvage est faible, même si une modification morphologique attribuable aux lâchers a été constatée dans la population sauvage en trente ans. Les conséquences écologiques pour la population réceptrice semblent donc limitées, mais une vigilance continue doit s'exercer concernant la diffusion de pathogènes (forte prévalence occasionnelle de virus Influenza A dans les élevages) et les risques génétiques associés au renforcement sur le long terme.
de Jocelyn Champagnon, Matthieu Guillemain, Johan Elmberg, Karin Folkesson, Michel Gauthier-Clerc
In Bird Study, 57(3) (2010), 344-351
Capsule Massive releases of captive-reared Mallard for hunting purposes have been practiced for 30 years. During this period the number of lamellae per centimetre of bill length in wild Mallard populations has decreased. Aims Every year since the 1970s, several million captive Mallard have been released in Europe. This may lead to a spread of unnatural phenotypes into the wild. Nevertheless, the consequences of such introductions have not been examined. Methods Two widespread and common migratory ducks were studied: Mallard Anas platyrhynchos and Teal A. crecca. Mallard is the only duck species for which stocking programmes occur, and Teal served as a control. In a 'before-after' design, we compared duck bill lamellar density over the last 30 years. Results Lamellar density in Mallard, but not Teal, decreased. The observed 10% decrease occurred in the first (proximate) centimetre of the bill, the most crucial in terms of food filtration. Conclusions We hypothesize that the change in bill morphology was because of the propagation of captive Mallard into the wild: captive Mallard eat mainly large items, relaxing the natural selection pressure maintaining high lamellar density for sieving small prey in wild ducks.
de Matthieu Guillemain, Johan Elmberg, Michel Gauthier-Clerc, Gregoire Massez, Richard Hearn, Jocelyn Champagnon, Géraldine Simon
In AMBIO, 39(2) (MAR 2010), 170-180
Animal populations are exposed to large-scale anthropogenic impact from e.g. climate change, habitat alteration and supplemental stocking. All of these may affect body condition in wintering dabbling ducks, which in turn may affect an individual's survival and reproductive success. The aim of this study was to assess whether there have been morphometric changes in Mallard (Anas platyrhynchos) and Teal (Anas crecca) over the last 30 years at a major wintering site. Body mass and condition increased from the 1950s-1960s to the 2000s in both species. The increase in body mass amounted to as much as 11.7%, with no corresponding change in body size. Improved body condition was maintained from early to mid-winter, but then converged with historical values for late winter. Our interpretation is that increasingly benign ambient winter conditions permit ducks to maintain better energetic "safety margins" throughout winter, and that converging spring departure values may be related to evolutionary flight energetic optima. The observed changes are consistent with large-scale climate amelioration and local/regional habitat improvement (both anthropogenic).
de Jocelyn Champagnon, Matthieu Guillemain, Michel Gauthier-Clerc, Jean-Dominique Lebreton, Johan Elmberg
In Wildfowl, 2 (2009), 184-191
En ligne : wildfowl.wwt.org.uk[...]
The release of captive-reared fish and game animals into the wild is a common management practice in Europe and North America. In Europe, millions of reared birds are released each year yet the consequences of these release programmes have received little attention. This paper describes the massive introduction of Mallard Anas platyrhynchos, a native migrant species released into the wild to increase the size of hunted populations. It provides the rationale for current and forthcoming experiments aimed at determining the effects of the augmentation of Mallard stocks on wild population genotype and survival rates.