Identification of environmental risk factors for the presence of Echinococcus multilocularis

International audience; The tapeworm Echinococcus multilocularis is dependent upon foxes and microtine rodents to complete its life cycle and is a parasite of public health importance causing the fatal zoonotic disease alveolar echinococcosis (AE). Concerns that AE could be in emergence in Europe have arisen from recent studies. In France, a monitoring survey led to the collection of 2813 georeferenced faecal samples of which 82 have been diagnosed positive for the presence of the parasite. A geographically weighted logistic regression was used to assess potential spatial variation in the effect of putative environmental risk variables. Landscape and climatic variables were expected to play…

Graphab

L’objectif du projet Graphab est de proposer et tester un ensemble de méthodes permettant d’estimer l’impact des grandes infrastructures de transport sur la distribution des espèces. Cette démarche part du constat que les études d’impact classiques sont limitées à une zone proche du tracé des infrastructures alors qu’un effet de barrière peut se produire à plus longue portée, si les espèces sont fortement dépendantes de leur réseau écologique. L’approche choisie pour modéliser les réseaux écologiques est celle des graphes paysagers, qui ont été couplés à des modèles de distribution d’espèces. En comparant les résultats de modèles de distribution de façon diachronique, avant et après la mise…

Editorial: Bourgogne Franche-Comté Nature est une revue scientifique

National audience; Face aux divers discours sur la crise environnementale et ses enjeux, l’actualité nous rappelle régulièrement comment le constat scientifique est mis au défi de la désinformation. Celle-ci s’exprime en pervertissant auprès du grand public l'espace offert par le doute critique (par exemple par les soi-disant climatosceptiques, les industriels de la chimie, etc.), ou par l'agora sans filtre d'internet où tous les avis apparaissent se valoir et entretiennent la confusion entre opinion et savoir. Les naturalistes, dans ce contexte, ont un rôle premier à jouer, en produisant des faits vérifiés, et donc en défendant publiquement la démarche et les connaissances scientifiques. L…

Caractérisation de la structure génétique des colonies de reproduction du petit rhinolophe en Franche-Comté

Accumulation and effects of Cd, Pb and Zn in blackbirds (Turdus merula) along a heavy metal pollution gradient.

Estimer l'impact des grandes infrastructures de transport sur la distribution des espèces : proposition et test d'un protocole méthodologique

Biodisponibilité et transfert d'éléments traces métalliques dans les réseaux trophiques terrestres.

National audience

Practices in research, surveillance and control of neglected tropical diseases by One Health approaches: A survey targeting scientists from French-speaking countries

One health (OH) approaches have increasingly been used in the last decade in the fight against zoonotic neglected tropical diseases (NTDs). However, descriptions of such collaborations between the human, animal and environmental health sectors are still limited for French-speaking tropical countries. The objective of the current survey was to explore the diversity of OH experiences applied to research, surveillance and control of NTDs by scientists from French-speaking countries, and discuss their constraints and benefits. Six zoonotic NTDs were targeted: echinococcoses, trypanosomiases, leishmaniases, rabies, Taenia solium cysticercosis and leptospiroses. Invitations to fill in an online q…

Assessing habitat connectivity of the lesser horseshoe bat using graph theory to explain its distribution

The lesser horseshoe bat, Rhinolophus hipposideros was formerly widespread and quite common in north-western Europe, but has undergone a dramatic decline from the 1960s. The main hypothesis for this decline is a change of habitat quality. Recent works have stressed the importance of good connection between roosts and foraging areas by tree lines and well-structured hedgerows. Thus, landscape connectivity is assumed to be a key-factor for population sustainability. The present study is based on a case study in Franche-Comté (France). Its purpose is to model the distribution of the lesser horseshoe bat and to characterize the functional connectivity of its habitat. Graph theory is used effici…

Caractérisation de la connectivité des habitats du petit rhinolophe en Franche-Comté

National audience

Estimation of water vole abundance by using surface indices

A method to estimate the abundance of the fossorial form of the water vole Arvicola terrestris scherman (Shaw, 1801) has been developed, by using surface indicies. Results are compared to the standard method of estimation using trap lines.

Numerical response of predators to large variations of grassland vole abundance and long‐term community changes

Abstract Voles can reach high densities with multiannual population fluctuations of large amplitude, and they are at the base of predator communities in Northern Eurasia and Northern America. This status places them at the heart of management conflicts wherein crop protection and health concerns are often raised against conservation issues. Here, a 20‐year survey describes the effects of large variations in grassland vole populations on the densities and the daily theoretical food intakes (TFI) of vole predators based on roadside counts. Our results show how the predator community responded to prey variations of large amplitude and how it reorganized with the increase in a dominant predator…

Spatial variability of biological and chemical contaminants in nurseries of lesser horseshoe bat : preliminary results in Franche-Comté (Eastern France)

Les "vagues voyageuses" du campagnol terrestre en Franche-Comté

Dans les prairies d'altitude, les dégâts provoqués par le campagnol terrestre posent un problème économique et agricole récurrent depuis le début des années 70. Dans la lutte contre cette peste agricole, l'utilisation croissante d'un anticoagulant rodenticide, la bromadiolone, a en plus considérablement augmenté la mortalité de nombreuses espèces animales, notamment de rapaces (légalement protégés), de renards et de sangliers. Dès le début du siècle, les recherches sur les variations de populations de rongeurs ont montré que la densité de certaines espèces de petits mammifères (lemmings, campagnols, etc.) fluctue de manière plus ou moins cyclique.

An agent-based model of a cutaneous leishmaniasis reservoir host, Meriones shawi

International audience; Meriones shawi (M.shawi) is the main reservoir host for zoonotic cutaneous leishmaniasis (ZCL) in Central Tunisia. The incorporation of environmental and climatic effects on the spread of ZCL in M. shawi remains difficult. This study presents an agent-based model (ABM) to overcome these difficulties and examine the impact of environment (i.e. vegetation cover) and climate (i.e. temperature) on M. shawi movement and prevalence. The model simulation considers two agent types: rodent agent and field unit agent. We tested the model according to two types of rodent movement: random and thoughtful. We integrated time dependent normalized difference vegetation index (NDVI) …

Lead concentrations in feathers and blood of common blackbirds (Turdus merula) and in earthworms inhabiting unpolluted and moderately polluted urban areas

9 pages; International audience; Despite the dramatic decrease of atmospheric lead (Pb) concentrations in urban areas of most industrialised countries, we hypothesised that urban common blackbirds (Turdus merula) may still be contaminated by Pb concentrations of toxicological concern due to transfer from soil through the food chain. We sampled blackbirds and earthworms, one of their main preys, in Besan?, a middle-size city of Eastern France (where atmospheric Pb concentrations decreased from 0.5 microg/m(3) in 1987 to nearly 0 in 2002) and in a rural reference site. Lead concentrations were determined in the tissues of the different functional groups of earthworms (anecic, epigeous and end…

Caractérisation de la structure génétique spatiale des populations de petits rhinolophes en Franche-Comté

Alveolar echinococcosis: characteristics of a possible emergence and new perspectives in epidemiosurveillance

International audience; The aim of this review is to discuss the situation of alveolar echinococcosis in France, in the light of the current knowledge on its transmission patterns in the world, especially Europe. An important risk of higher contamination of the rural environment may be suspected from newly reported cases of infected foxes or voles in several countries where the disease was not found before. Furthermore, the increase of prevalence rate in foxes in Bade-Würtemberg (Germany) and Franche-Comté (France), traditionally endemic, is also in support of this new trend. Urban foxes and the spreading of infected foxes to cities may also be the cause of the extension to urban and suburb…

Coupling agent-based with equation-based models to study spatially explicit megapopulation dynamics

International audience; The incorporation of the spatial heterogeneity of real landscapes into population dynamics remains extremely difficult. We propose combining equation-based modelling (EBM) and agent-based modelling (ABM) to overcome the difficulties classically encountered. ABM facilitates the description of entities that act according to specific rules evolving on various scales. However, a large number of entities may lead to computational difficulties (e.g., for populations of small mammals, such as voles, that can exceed millions of individuals). Here, EBM handles age-structured population growth, and ABM represents the spreading of voles on large scales. Simulations applied to t…

Campagraphe

Les moyennes montagnes du Jura et de l'Auvergne sont régulièrement envahies par un rongeur prairial, le campagnol terrestre. La connectivité des surfaces de prairies étant un des facteurs favorisant cette propagation, le projet vise à utiliser une modélisation du réseau prairial fondée sur les graphes paysagers comme un guide pour expérimenter des actions de lutte sur le terrain. A partir de ces modèles, il s'agira tout d'abord de délimiter des entités fonctionnelles reposant sur la notion de synchronie, pour proposer des zonages adaptés au suivi des populations, tel qu'il est effectué par les partenaires professionnels impliqués dans la lutte contre les pullulations. Les graphes paysagers …

Numerical response of predators to large variations of grassland vole abundance, long-term community change and prey switches

AbstractVoles can reach high densities with multi-annual population fluctuations of large amplitude, and they are at the base of large and rich communities of predators in temperate and arctic food webs. This status places them at the heart of management conflicts wherein crop protection and health concerns are often raised against conservation issues. Here, a 20-year survey describes the effects of large variations in grassland vole populations on the densities and the daily theoretical food intakes (TFI) of vole predators based on roadside counts. Our results show how the predator community responds to prey variations of large amplitude and how it reorganized with the increase in a domina…

Consequences of organ choice in describing bacterial pathogen assemblages in a rodent population

SUMMARYHigh-throughput sequencing technologies now allow for rapid cost-effective surveys of multiple pathogens in many host species including rodents, but it is currently unclear if the organ chosen for screening influences the number and identity of bacteria detected. We used 16S rRNA amplicon sequencing to identify bacterial pathogens in the heart, liver, lungs, kidneys and spleen of 13 water voles (Arvicola terrestris) collected in Franche-Comté, France. We asked if bacterial pathogen assemblages within organs are similar and if all five organs are necessary to detect all of the bacteria present in an individual animal. We identified 24 bacteria representing 17 genera; average bacterial…

Population dynamics of fossorial water vole (Arvicola terrestris scherman): a land use and landscape perspective

Abstract This study investigates the effect of land use, and landscape composition and structure on the population dynamics of fossorial water vole (Arvicola terrestris scherman Shaw). Water vole populations were monitored from 1989 to 1994 in the Doubs department, France, by using index methods. Land use patterns were studied based on agriculture and forestry data from the French Ministry of Agriculture collected in 1956, 1970, 1979 and 1988. Grassland quality and landscape structure were studied based on field transects, combined with the assessment of landscape structure from maps at 1:25,000 scale. Outbreaks of water vole populations occurred as a wave, spreading from epicentres over mo…

Effect of landscape structure on common vole (Microtus arvalis) distribution and abundance at several space scales

This paper aims to answer the following question: are the fluctuations of abundance of Common Vole (Microtus arvalis) specific to different types of landscapes? The research was carried out in landscapes where grassland was dominant. The sampling method was based upon a partition in both landscape types and landscape units. Tracking of vole indices was used to evaluate their relative abundance. Six landscape transects were sampled during two successive years. Results show that population variation and diffusion of demographic states are closely related to landscape types. The possible causes of this are discussed. The landscape units can be used as global variables to assess outbreak risk a…

Influence of landscape composition and diversity on contaminant flux in terrestrial food webs: a case study of trace metal transfer to European blackbirds Turdus merula.

13 pages; International audience; Although understanding the influence of the spatial arrangement of habitats and interacting communities on the processes of pollutant flux and impacts is critical for exposure and risk assessment, to date few studies have been devoted to this emergent topic. We tested the hypothesis that landscape composition and diversity affect the transfer of trace metals to vertebrates. Bioaccumulation of Cd and Pb in blood and feathers of European blackbirds Turdus merula (n=138) was studied over a smelter-impacted area (Northern France). Landscape composition (type and occurrence of the different habitats) and diversity (number of different habitat types and the propo…

Representing Echinococcus multilocularis gradients in space and time: fox data, models, and scale dependence

International audience

Mortality and demographic recovery in early post-black death epidemics: Role of recent emigrants in medieval Dijon

International audience; Objective and methodsWe analyze the influence of population movement on susceptibility to death and resilience during two epidemics occurring in Dijon soon after the Black Death. Using a specific program designed to propose links between entries in annual tax registers, we define tentative heads of household, the elapsed time since their first registration and their ties with other persons within the city.ResultsDuring the 1400 epidemic heads of household who were registered for 1–3 years die in large numbers, whereas during years without epidemics, their death rate is lower than that of heads of household who were registered longer. Recent registration is an epidemi…

Trophic transfer of pesticides: The fine line between predator–prey regulation and pesticide–pest regulation

International audience; Understanding pesticide impacts on populations of target/non-target species and communities is a challenge to applied ecology. When predators that otherwise regulate pest densities ingest prey contaminated with pesticides, this can suppress predator populations by secondary poisoning. It is, however, unknown how species relationships and protocols of treatments (e.g. anticoagulant rodenticide [AR]) interact to affect pest regulation.To tackle this issue, we modelled a heuristic non-spatialized system including montane water voles, specialist vole predators (stoats, weasels) and a generalist predator (red fox) which consumes voles, mustelids and other prey. By carryin…

Karyological and dental identification of Microtus limnophilus in a large focus of alveolar echinococcosis (Gansu, China).

International audience; A study of voles (Arvicolidae, Rodentia) from Gansu (China) designed to identify a potential host of Echinococcus multilocularis, responsible for human alveolar echinococcosis, leads to a general analysis of Microtus limnophilus population karyotypes, M1 of M. oeconomus populations from all of Eurasia and of M. limnophilus of Mongolia. The Microtus of Gansu belonging to the nominal subspecies M. limnophilus limnophilus (2n = 38; NF = 58) differs markedly in size and shape of M1 from the M. limnophilus of Mongolia, which must therefore be considered as a new subspecies M. limnophilus of malygini nov. ssp. (2n = 38; NF = 60) and the M. oeconomus of Mongolia should be r…

Les graphes paysagers pour la modélisation et la gestion des pullulations de campagnols terrestres.

International audience; Les prairies d’Auvergne et de Franche-Comté sont régulièrement envahies par un rongeur, le campagnol terrestre. Le projet CAMPAGRAPHE vise à fournir un appui pour la mise en place d’un dispositif agro-écologique limitant sa diffusion grâce à une modélisation des réseaux de prairies.Le graphe obtenu permet de localiser des actions de terrain et orienter le suivi des populations.

La génétique au service de l'étude des espèces : y a-t'il des échanges entre les colonies de petits rhinolophes en Franche-Comté ?

Graphab 2

For some ten years, landscape graphs have been widely used for modeling ecological networks and measuring landscape connectivity from an operational perspective. A landscape graph is a set of nodes (habitat patches for a given species or group species) potentially connected by links representing the functional connectivity between each pair of nodes. With their simple design and their ecological relevance, graph-based methods can serve as a guide for planning decision-making, especially for the conservation of ecological networks. In this perspective, Graphab 2 project aims to use landscape graphs to assess the impact of transport infrastructures on the functionality of ecological networks,…

Effet du contexte paysager sur la cinétique de population du campagnol terrestre (Arvicola terrestris scherman)

Environmental risk factors for transmission and representing Echinococcus multilocularis gradients in space and time: fox data, models and scale dependence

International audience

Data from: Investigating hybridization between the two sibling bat species Myotis myotis and M. blythii from guano in a natural mixed maternity colony

Because they can form seasonal mixed-species groups during mating and maternal care, bats are exciting models for studying interspecific hybridization. Myotis myotis and M. blythii are genetically close and morphologically almost identical, but they differ in some aspects of their ecology and life-history traits. When they occur in sympatry, they often form large mixed maternity colonies, in which their relative abundance can vary across time due to a shift in the timing of parturition. For the first time, we used non-invasive genetic methods to assess the hybridization rate and colony composition in a maternity colony of M. myotis and M. blythii located in the French Alps. Bat guano was co…