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Understanding and predicting population response to anthropogenic disturbance: current approaches and novel opportunities
No full textInternational audienceEffective conservation of biodiversity depends on the successful management of wildlife populations and their habitats. Successful management, in turn, depends on our ability to understand and accurately forecast how populations and communities respond to human‐induced changes in their environments. However, quantifying how these stressors impact population dynamics remains challenging. Another significant hurdle at this interface is determining which quantitative approach(es) are most appropriate given data types, constraints and the intended purpose. Here, we provide a cross‐taxa overview of key methodological approaches (e.g., matrix population models) and model elements (e.g., energetics) that are currently used to model the effects of anthropogenic disturbance on wildlife populations. Specifically, we discuss how these modelling approaches differ in their key assumptions, in their structure and complexity, in the questions they are best poised to address and in their data requirements. Our intention is to help overcome some of the methodological biases that might persist across taxonomic specialisations, identify new opportunities to address existing modelling challenges and improve scientific understanding of the direct and indirect impacts of anthropogenic disturbance. We guide users through the identification of appropriate model configurations for different management purposes, while also suggesting key priorities for model development and integration
Découverte des deux espèces d’Aloina Kindb. à la Villa Baulieu (Rognes, 13840)
No full textInternational audienceThe Domaine de Baulieu is located in the commune of Rognes, a few kilometers north of Aix-en-Provence. At the request of the current occupant, FLC Group, and in collaboration with Mibelle Group Biochemistry, a study was carried out to investigate the presence of a moss species: Aloina aloides. After surveying the entire area, four distinct populations of A. aloides were potentially identified in the park. Genetic analyses were carried out to validate the identification. The species A aloides is indeed present on the site, but various sequences attributed to moss species have also been identified, including another Aloina species, A. rigida. The coexistence of the two Aloina species, which present morphological and ecological differences, is an unexpected result.Le domaine de Baulieu est situé sur la commune de Rognes à quelques kilomètres au nord d’Aix-en-Provence. A la demande de l’actuel occupant, FLC Group, et en collaboration avec Mibelle Group Biochemistry, une étude a été menée pour rechercher la présence d’une espèce de mousse sur le domaine : Aloina aloides. Après prospection de l’ensemble du domaine, quatre populations distinctes d’A. aloides ont été potentiellement identifiées dans le parc. Afin de valider l’identification, des analyses génétiques ont été réalisées. L’espèce A. aloides est bien présente sur le site mais différentes séquences attribuées à des espèces de mousses sont également relevées dont une autre espèce d’Aloina, A. rigida. La coexistence des deux espèces d’Aloina qui présentent des différences morphologiques et écologiques, est un résultat inattendu
Diagnostic des pressions sur la biodiversité sur le territoire de Nantes Métropole - Rapport de synthèse
No full textReprésentations des activités humaines dans le cadre de l'élaboration du DOCOB du site Natura 2000 de la Baie de Chingoudy: Apports méthodologiques et retours d'expériences
No full textCe webinaire du GIS HomMer #9 qui a lieu ce jeudi 16 janvier (11h00-12h00), durant lequel une équipe composée de membres du laboratoire Territoires, Villes, Environnement et Société (TVES - ULR 4477), de CAPENA (Centre pour l'Aquaculture, la Pêche et l'Environnement de Nouvelle-Aquitaine) et de l'OFB présentera à trois voix un travail sur les "Représentations des activités humaines dans le cadre de l'élaboration du DOCOB de la Baie de Chingoudy : apports méthodologiques et retours d'expériences". L'étude réalisée dans ce site Natura 2000 a permis de développer une méthode pour comprendre les jeux d'acteurs et leurs représentations, afin de renforcer leur implication. La présentation se poursuivra par des échanges.Ce webinaire du GIS HomMer #9 qui a lieu ce jeudi 16 janvier (11h00-12h00), durant lequel une équipe composée de membres du laboratoire Territoires, Villes, Environnement et Société (TVES - ULR 4477), de CAPENA (Centre pour l'Aquaculture, la Pêche et l'Environnement de Nouvelle-Aquitaine) et de l'OFB présentera à trois voix un travail sur les "Représentations des activités humaines dans le cadre de l'élaboration du DOCOB de la Baie de Chingoudy : apports méthodologiques et retours d'expériences". L'étude réalisée dans ce site Natura 2000 a permis de développer une méthode pour comprendre les jeux d'acteurs et leurs représentations, afin de renforcer leur implication. La présentation se poursuivra par des échanges
Alternative resource or opportunism? Use of oyster farms by Eurasian Oystercatcher Haematopus ostralegus in the Golfe du Morbihan.
No full textInternational audienceThe Eurasian Oystercatcher (Haematopus ostralegus) is considered endangered in Europe due to intertidal habitat loss and overexploitation of its prey. In contrast to the broader European decline, the breeding population in the Golfe du Morbihan has increased steadily since the first breeding record in 2010, reaching 62 pairs in 2024. The wintering population has also grown markedly, from fewer than 100 individuals in 2010 to around 300 in 2024.This positive local trend led to the launch of a tagging and color-ringing program in 2021 to better understand habitat use. GPS tracking showed that some individuals spend up to 32% of their time on oyster farms, with use strongly influenced by tidal cycles. Oyster farming, mainly of the Pacific oyster (Magallana gigas), covers about 13% of the Golfe and represents a significant anthropogenic habitat modification.Oystercatchers forage on mudflats, rocky shores, and oyster farming areas. Feeding directly on farmed oyster beds is a poorly documented behavior, prompting dedicated field monitoring in 2024. Preliminary results indicate a low feeding rate on farmed oysters (0.25 oysters/min/bird), much lower than published values for wild oysters (around 1.2 oysters/min/bird), with nearly twice as many failures as successful attempts. Ongoing research aims to assess the nutritional value of this foraging strategy and its contribution to supporting breeding and wintering populations in the Golfe du Morbihan
Seasonal variations in planktonic food web structure affect stability by shifting the distribution of energy fluxes
No full textInternational audienceSeasonality in temperate ecosystems shapes species phenology, influencing interactions and food web structure. Variations in species richness and biomass affect trophic interaction strength, a crucial factor for community stability, which can be assessed through energy fluxes – an essential indicator of ecosystem function. Yet, we still have limited understanding on how energy fluxes and food web structure vary overtime and how the seasonal dynamics influence stability. We examined how the structure, energy fluxes and stability of a highly resolved multitrophic lake food web change across seasons. Two estimates representing different facets of stability were considered: resilience and reactivity. We found a strong seasonal pattern in food web structure, with higher complexity observed in summer and autumn. In addition, we found that more complex food webs are more reactive to perturbations, and consequently, less stable than simpler ones over short time‐scale. This was influenced by a lower proportion of strong energy fluxes. Resilience was unaffected by seasonality, food web structure and energy fluxes, highlighting the need to account for multifaceted nature of stability. The seasonal variability of stability suggests that food webs may vary temporally in their vulnerability to environmental perturbations, which has important implications for ecosystem management
Pressured researchers in ecology and conservation demand support to guarantee fair interactions with stakeholders
No full textInternational audienceFacing the current decline of biodiversity, researchers in ecology and conservation interact with socioeconomic stakeholders to involve their research more closely with society. Yet previous research in other domains showed that these interactions sometimes affect the well-being of researchers and the balance between private and public interests in science.We conducted a survey aiming to assess the different outcomes of these interactions to highlight benefits and disadvantages depending on the types of stakeholders. We asked French researchers in ecology and conservation to describe their experiences with different stakeholders. We also asked them to identify the most relevant institutional organisations to supervise collaborations and to provide support to mitigate the potential impacts of negative interactions with socioeconomic stakeholders. (...)
SEMSOP. Sensibilité du Microbiome du Sol aux Produits phytopharmaceutiques : Implications pour la santé humaine et les écosystèmes à La Réunion. Webinaire de présentation du projet
No full textSource Agritrop Cirad (https://agritrop.cirad.fr/616085/) * Autres projets (id;sigle;titre): ;SEMSOP;(FRA) SEnsibilité du Microbiome du SOl aux Produits phytopharmaceutiques : Implications pour la santé humaine et les écosystèmes à La Réunion//International audienc
Overview and dynamics of benthic cyanobacteria in water bodies in mainland France
No full textInternational audienceAlthough less studied than their planktonic counterparts, benthic cyanobacteria in water bodies may represent a major health and ecological issue due to their ability to produce a broad spectrum of cyanotoxins. Apart from a few descriptive studies, often triggered by cases of animal poisoning, their spatial and temporal dynamics, as well as their taxonomic diversity, remain largely unknown in French freshwater ecosystems.In recent years, their presence has been mentioned with increasing frequency in surveys carried out to monitor the ecological status of water bodies, raising a central question: are we really witnessing an increase in their occurrence - under the effect of global change and anthropogenic pressures - or is this an old phenomenon that has simply been neglected until now?Against this backdrop, this study offers an initial overview of benthic cyanobacteria in lakes in mainland France. It is based on the analysis of data collected between 2006 and 2024, as part of the macrophyte sampling protocols used to assess the ecological status of lakes, as required by the Water Framework Directive. As colonies of benthic cyanobacteria are visible to the naked eye, they are counted during these campaigns and then identified in the laboratory.The aim of this work is to (1) characterize the geographical and temporal distribution of these organisms, (2) identify taxa which may produce cyanotoxin, (3) locate areas of high abundance, and (4) initiate the identification of environmental factors influencing the abundance of benthic cyanobacteria.The initial results, presented here in the form of maps and graphical analyses, have already enabled us to identify trends and gain a better understanding of the environments concerned. These initial findings show the presence of benthic cyanobacteria able to emit toxins in approximately 2/3rd of studied lakes