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The Interplay of Climate Change, Urbanisation, and Species Traits Shapes European Butterfly Population Trends
No full textInternational audienceABSTRACT Aim To examine how butterfly population trends respond to climate change and urbanisation at a continental scale, and whether responses differ between urban and rural environments. Location 869 sites across 12 European countries, spanning six bioclimatic zones. Time Period 1976–2021. Major Taxa Studied Butterflies (Lepidoptera). Methods We analysed long‐term monitoring data from > 8400 populations of 145 species representing a wide range of ecological and life‐history traits. Population trends were modelled in relation to climate variables (temperature, precipitation and aridity), urbanisation (built‐up surface), and their interactions with urban context (urban vs. rural) and species traits (trophic specialisation, body size, reproductive rate and thermal adaptation). Results Climate warming and aridification were consistently linked to population declines in both rural and urban contexts, while precipitation effects varied by location and species. Urbanisation alone did not predict trends, but the urban–rural context strongly modulated species' responses to warming, indicating potential synergies between climate change and urbanisation. The stronger impact of warming in urban populations likely reflects elevated baseline temperatures and reduced habitat suitability and connectivity in urban landscapes, limiting thermal buffering. Species with colder thermal niches and lower reproductive rates were most vulnerable to warming, as warming exceeds the thermal optima of cold‐adapted species and lower reproductive rates limit their capacity to buffer climate‐driven population declines. Under aridification, which can reduce host‐plant availability, trophic specialists declined more in urban areas, whereas generalists unexpectedly declined more in rural sites, suggesting context‐dependent constraints under increasing water limitation. Main Conclusions Our findings highlight the complex interplay between climate change, urban context, and species traits in driving population dynamics. Importantly, our results suggest that urbanisation generally amplifies the negative impact of climate change on insect population trends
Different temperature responses of mountain rockwalls, soils, and lakes to summer heat waves
No full textInternational audienceMountain ecosystems are highly sensitive to climate variations. At fine spatial scales, high-elevation microclimates play a critical role in shaping biodiversity, hydrological processes, and ecosystem services, while also influencing the occurrence of natural hazards such as landslides, avalanches, and floods. Heat waves, which have been increasing in frequency and intensity due to global climate change, present significant challenges to these vulnerable environments. This study examines the impacts of summer heat waves on mountain microthermal conditions in three compartments: rockwalls, soils, and lakes. We assembled data across a latitudinal and elevational gradient in the French Alps including years of two recent heat wave events (2015 and 2022). We calculated thermal indicators to evaluate the buffering or amplifying effects of the atmospheric signal on the investigated compartments. The average summer temperature and the growing/thawing degree days were more responsive to heat waves than the phenological indicator (e.g., spring mixing date in lakes) and maximum temperature. We found significant anomalies for both the 2015 and 2022 heat waves across almost all compartments and indicators. Lakes tended to amplify atmospheric temperatures (especially in 2022) whereas rockwalls and soils tended to buffer them. However, residues from the relationship between compartment and atmospheric temperatures were large during heat waves, suggesting that these events may reduce the compartments’ buffering capacity. Our study underscores the importance of long-term monitoring of microthermal conditions to provide a more integrative assessment of mountain ecosystem response to extreme meteorological events
Rapport sur les prélèvements de tourterelles des bois et le respect du quota cynégétique durant la saison de chasse 2025-26
No full textEtat des lieux de la restauration écologique des milieux marins et littoraux en France : analyse des données issues de la plateforme LITTOREX
No full textNational audienceLa restauration écologique des milieux marins s'impose désormais comme une démarche incontournable pour la préservation de leur fonctionnement et des services qu'ils rendent aux sociétés. Elle s'inscrit notamment dans le cadre de la Décennie des Nations Unies pour la Restauration des Ecosystèmes (2021-2030) et le Règlement européen sur la Restauration de la Nature adopté en 2024. Afin de structurer les connaissances existantes, de partager les retours d'expérience et ainsi favoriser l'efficacité des opérations de restauration au niveau national, l'OFB et le BRGM développent depuis plusieurs années la plateforme LITTOREX dédiée au recensement des projets de restauration. L'analyse des 72 premiers retours d'expérience intégrés à cette plateforme constitue, à ce jour, l'un des états des lieux les plus complets sur les pratiques de restauration écologique en milieux marins et littoraux en France. Les actions recensées concernent majoritairement des écosystèmes de transition intertidaux (marais, herbiers, dunes) reflétant notamment la dynamique internationale de politiques publiques promouvant l'adaptation face au changement climatique. Les projets sur les milieux subtidaux sont aujourd'hui moins documentés soulignant l'importance de compléter le recensement. Par ailleurs, cette analyse montre que les dispositifs de suivi appliqués demeurent hétérogènes, de courte durée et rarement fondés sur des indicateurs traduisant la complexité structurelle, fonctionnelle et sociale de milieux restaurés. Cela a pour effet de limiter l'évaluation de l'efficacité des mesures employées ainsi que la comparabilité inter-sites. Ainsi, si la restauration écologique apparait comme un levier prometteur pour améliorer l'état de conservation des écosystèmes marins et littoraux, les résultats de cette étude révèlent la nécessité de renforcer les suivis à long terme, de mieux documenter les échecs et d'harmoniser les méthodes en définissant un cadre national d'évaluation scientifique. Elle met aussi en avant l'importance d'impliquer les acteurs afin d'enrichir LITTOREX et de capitaliser les retours d'expérience pour diffuser les bonnes pratiques
Waterfowl Move Less in Heterogeneous and Human‐Populated Landscapes, With Implications for Spread of Avian Influenza Viruses
No full textInternational audienceABSTRACT Animal movements contribute to the spread of infectious diseases and are driven in part by environmental conditions. We investigated the links among the environment, animal movement, and infectious disease dynamics in waterfowl, which are among the primary wildlife hosts of avian influenza viruses. By combining telemetry data on 4606 individuals from 26 waterfowl species with data on land cover, weather, and vegetation, we found that waterfowl moved less in areas of higher land cover heterogeneity and higher human population density. Moreover, predicted waterfowl movement distances were weakly but positively correlated with distances between detections of H5N1 highly pathogenic avian influenza in wild waterfowl, suggesting that environmental conditions might contribute to the spread of this disease via their effects on bird movements. By considering wildlife movements alongside other drivers of infectious disease dynamics, such as livestock production and human mobility, we move closer to predicting outbreaks and informing interventions
Understory plant indicator values poorly perform at monitoring temporal changes in French forest soil chemical properties
No full textInternational audienceUnderstory plant communities are widely used to infer soil conditions through species indicator values (IVs), scores reflecting species’ ecological preferences for factors such as soil acidity, moisture, or nutrient levels. While their reliability to describe soil conditions along spatial gradients is well established, their ability to capture temporal changes in soil chemistry remains largely untested at both temporal and geographical scales. We combined 26 years of vegetation monitoring with two French national soil surveys (1993–1997; 2007–2012) across 102 permanent forest plots to assess the reliability of community soil indices (CSIs) as bioindicators of soil pH, carbon-to-nitrogen ratio (C/N), and extractable phosphorus. CSIs were computed by averaging species IVs for each plot and survey. Temporal dynamics of measured soil properties and CSIs were analyzed using mixed-effects models at the national scale, while local trends were estimated separately for each plot to directly compare measured and vegetation-inferred changes. CSIs showed strong spatial correlations with measured pH and C/N, but weaker relationships for phosphorus. In contrast, no significant coupling was found between temporal changes in CSIs and measured soil parameters, with frequent mismatches in both direction and magnitude at the plot level. Measured soil dynamics were mainly driven by initial edaphic conditions and stand age, whereas CSI dynamics responded primarily to canopy openness and anthropogenic disturbances such tree harvesting. These findings confirm the value of IVs for spatial bioindication but highlight their limited sensitivity for detecting long-term soil changes, especially where soil changes remain modest
Notice CarHab - Programme de cartographie nationale des habitats naturels et semi-naturels
No full textLaunched as part of the 2011–2020 National Biodiversity Strategy, this program, led by the Ministry of Ecology, aims to address the challenges of biodiversity conservation, land-use planning, and the sustainable management of natural resources. Its objective is to produce a national map by modeling natural and semi-natural terrestrial habitats in mainland France and overseas territories at a scale of 1:25,000.The results enable the preliminary identification of habitats and support national and regional public policies related to land use planning and biodiversity knowledge. This report describes the methodology used to produce the maps, the key concepts for defining habitats, as well as the various maps produced and recommendations for their use.Initié dans le cadre de la stratégie nationale pour la biodiversité 2011-2020, ce programme porté par le Ministère en charge de l'écologie vise à répondre aux enjeux de conservation de la biodiversité, d'aménagement du territoire et de gestion durable des ressources naturelles. Il a pour objectif de réaliser une cartographie nationale par modélisation des habitats naturels et semi-naturels terrestres de métropole et d'outre-mer, à l'échelle du 1/25000e.Les résultats permettent de pré-localiser les habitats et viennent en appui aux politiques publiques nationales et territoriales en lien avec l'aménagement du territoire et la connaissance de la biodiversité. Ce rapport décrit la méthodologie de production des cartographies, les concepts clés régissant la définition des habitats, ainsi que les différentes cartes produites et leurs recommandations d'utilisation
Determinism of age and length at first return in sea trout (S. trutta)
No full textInternational audienc
Agroecological performances of low pesticide used grapevine systems adapted to six diverse regional contexts in France
No full textInternational audienceCONTEXT: Viticulture extensively employs pesticides to ensure its yield and quality targets. Vineyards are often characterised by low biodiversity and limited use of agroecological practices. The long-term sustainability of viticulture is dependent on the reduction of pesticide use. Designing and assessing innovative agroecologicalvineyards is a relevant approach to achieve this objective of french policies.OBJECTIVES: The objectives of the study are: i) to develop a participatory method of cropping system prototyping to meet the agroecological challenges and particularly the reduction in pesticide use, ii) implement this method on grapevine systems at the national scale and iii) assess the agronomical and economical performances of the prototypes.METHODS: This study presents an innovative methodology based on the prototyping of grapevine systems (GCS) with a participatory approach for knowledge-sharing. This approach was adapted to suit perennial crops and implemented through the EcoViti network of experimental sites located in six contrasted vineyards in France. The Efficiency-Substitution-Redesign (ESR) framework was used to categorise the 45 vineyard prototypes.Then, a multi-criteria assessment method encompassing agronomic, environmental, and socio-economic aspects was conducted to get a comprehensive analysis of the prototypes. From 2013 to 2018, data were collected to assess the 45 vineyard prototypes. To represent french vineyards, 93% of the vineyard prototypes wereimplemented on already planted vineyards, incorporating decision support tools, prophylactic practices, and biocontrol levers. And 7% of the vineyard prototypes were based on newly planted vineyards with innovative varieties (resistant to mildews).RESULTS AND CONCLUSION: 45 grapevine systems across 27 experimental sites were prototyped with combined agroecological practices. The multi-criteria performance assessment revealed that all agronomic, environmental and socio-economic goals of the ESR rating scale could be attained, ensuring sustainability. Forty-one of the 45prototypes exhibited a pesticide reduction exceeding 50% on average between 2013 and 2018. Moreover, 40 prototypes successfully met yield and harvest quality objectives, while 92% of the prototypes achieved the targeted workload goals.SIGNIFICANCE: This study produced relevant and regionally tailored grapevine systems fitted to reduce significantly pesticide use. Our findings underscore the significance of knowledge-sharing in facilitating the overall redesign process. The vineyard prototypes presented herein are not prescriptive solutions but rather indicative ofthe avenues through which winegrowers can customise and devise their unique pathways of agroecological transition for their vineyard
Recommendations for Improving the Modeling of Wintering Waterbird Population Sizes and Trends
No full textInternational audienceBiodiversity monitoring at large spatial and temporal scales is essential for informing conservation policies. The International Waterbird Census (IWC) is one of the longest‐running global citizen science monitoring schemes, providing critical information to several international agreements. However, analyzing IWC count data poses statistical challenges, including zero inflation, overdispersion, spatial autocorrelation, and missing data. While various modeling approaches have been used to estimate waterbird population size and trends, their ability to handle these issues and the implications for trend estimates remain unassessed. Using IWC count data from five species in the East Atlantic Flyway, we compared four modeling approaches: TRIM (TRends and Indices for Monitoring data), LORI (Low‐Rank Interactions), and two generalized linear mixed models (GLMMs) with simple or optimized parametrizations. We benchmarked their performance in addressing zero inflation, overdispersion, and spatial autocorrelation across different realistic sampling designs (i.e., alternative dataset configurations). Our results highlight significant limitations in commonly used methods. Simple GLMMs, TRIM, and LORI generally failed to mitigate both zero inflation and overdispersion. In contrast, optimized GLMMs improved model convergence and better addressed these issues by selecting appropriate probability distributions. However, no single distribution performed consistently well across species and sampling designs. Spatial structures were effective in reducing spatial autocorrelation in most cases. We recommend a careful species‐specific selection of statistical methods when analyzing count data, as inadequate models may misrepresent population trends and thus misguide conservation efforts. Future research should explore the integration of advanced hierarchical and spatio‐temporal models to improve inference from large‐scale citizen science datasets