French birds lag behind climate warming

Biodiversity responses to climate warming have been documented through the study of changes in distributions, abundances or phenologies of individual species or in more integrated measures such as species community richness and composition. However, whether these observed population and community changes are occurring fast enough to cope with new climatic conditions remain uncertain and hardly quantifiable. Here, using spatial and temporal trends from the French breeding bird survey, we show that although bird assemblages are strongly responding to climate warming, this response is slower than expected for catching up with the current temperature increase. During the last two decades, French birds have only achieved 54% of the response required to follow temperature increase, and have accumulated, in 18 years, a 97 km delay in their northward shift. We thus developed a framework to measure both the observed and predicted response of species assemblage to climate change, an approach which is flexible enough to be applicable to any taxa with large-scale survey data, using either abundance or distribution data. For example, it can be further used to test if different delays are found across groups or if, for a given group, the delay depends on the land-use contexts

Estimation of species relative abundances and habitat preferences using opportunistic data

We develop a new statistical procedure to monitor, with opportunist data, relative species abundances and their respective preferences for dierent habitat types. Following Giraud et al. (2015), we combine the opportunistic data with some standardized data in order to correct the bias inherent to the opportunistic data collection. Our main contributions are (i) to tackle the bias induced by habitat selection behaviors, (ii) to handle data where the habitat type associated to each observation is unknown, (iii) to estimate probabilities of selection of habitat for the species. As an illustration, we estimate common bird species habitat preferences and abundances in the region of Aquitaine (France)

Vigie-Nature, un réseau de citoyens qui fait avancer la science

Recueillir des données sur la biodiversité afin d’appréhender sa complexité et de mesurer et comprendre son érosion, en associant cette collecte d’informations par les citoyens à un projet de recherche : tels sont les objectifs de Vigie-Nature, un dispositif de science participative basé sur un partenariat original entre les scientifiques et le public

Metacommunity Dynamics: Decline of Functional Relationship along a Habitat Fragmentation Gradient

Background: The metacommunity framework is crucial to the study of functional relations along environmental gradients. Changes in resource grain associated with increasing habitat fragmentation should generate uncoupled responses of interacting species with contrasted dispersal abilities. Methodology/Principal Findings: Here we tested whether the intensity of parasitism was modified by increasing habitat fragmentation in the well know predator-prey system linking the parasitoid Cotesia glomerata (Hymenoptera: Braconidae) to its main host Pieris brassicae (Lepidoptera: Pieridae). We collected information on herbivorous abundance and parasitism rate along an urbanization gradient from the periphery to the centre of Paris. We showed that butterfly densities were not influenced by habitat fragmentation, whereas parasitism rate sharply decreased along this gradient. Conclusions/Significance: Our results provide novel insights into the mechanisms underlying the persistence of species in highly fragmented areas. They suggest that differential dispersal abilities could alter functional relationships between prey and predator, notably by a lack of natural predators

Measuring epistemic success of a biodiversity citizen science program: A citation study

This paper offers a comparative evaluation of the scientific impact of a citizen science program in ecology, ‘‘Vigie-Nature”, managed by the French National Museum of Natural History. Vigie-Nature consists of a national network of amateur observatories dedicated to a participative study of biodiversity in France that has been running for the last twenty years. We collected 123 articles published by Vigie-Nature in international peer-reviewed journals between 2007 and 2019, and computed the yearly amount of citations of these articles between 0–12 years post-publication. We then compared this body of citations with the number of yearly citations relative to the ensemble of the articles published in ecology and indexed in the ‘‘Web of Science” data-base. Using a longitudinal data analysis, we could observe that the yearly number of citations of the Vigie-Nature articles is significantly higher than that of the other publications in the same domain. Furthermore, this excess of citations tends to steadily grow over time: Vigie-Nature publications are about 1.5 times more cited 3 years after publication, and 3 times more cited 11 years post-publication. These results suggest that large-scale biodiversity citizen science projects are susceptible to reach a high epistemic impact, when managed in specific ways which need to be clarified through further investigations

Les dynamiques spatio-temporelles de l'occupation du sol en Seine-et-Marne et leurs conséquences sur la biodiversité

International audienceLes modifications de l'occupation du sol liées aux évolutions multidimensionnelles des territoires (démographie, infrastructures, urbanisation,…) constituent l'une des causes majeures de la perte globale de la biodiversité. Pour faire face aux enjeux associés, les acteurs de l'aménagement et de la gestion des territoires doivent pouvoir articuler la préservation de la biodiversité et leurs pratiques. La création d'outils d'aide à la décision basés sur des observations fiables apparaît nécessaire. L'Atlas dynamique de la biodiversité (co-construction CG Seine-et-Marne, UMR 7204 CERSP, UMR 7533 LADYSS) a pour objectif de fournir un tel outil, qui détaillera de façon spatiale et temporelle la biodiversité du département ainsi que les pressions anthropiques qui la menacent. Cette présentation fait une synthèse de l'approche et des résultats obtenus lors de travaux engagés dans le cadre d'une thèse inscrite dans le développement de cet outil. L'objectif est d'établir les conséquences des dynamiques spatio-temporelles de l'occupation du sol sur la biodiversité fonctionnelle de Seine-et-Marne depuis les années 80. A la croisée de la géographie et de l'écologie, ce travail présente la particularité d'une approche intégrative allant de la description des dynamiques spatiales de l'occupation du sol à la création de modèles permettant de comprendre et visualiser les modifications de la diversité fonctionnelle depuis les années 80

Capitalising on Opportunistic Data for Monitoring Species Relative Abundances

With the internet, a massive amount of information on species abundance can be collected under citizen science programs. However, these data are often difficult to use directly in statistical inference, as their collection is generally opportunistic, and the distribution of the sampling effort is often not known. In this paper, we develop a general statistical framework to combine such ``opportunistic data'' with data collected using schemes characterized by a known sampling effort. Under some structural assumptions regarding the sampling effort and detectability, our approach allows to estimate the relative abundance of several species in different sites. It can be implemented through a simple generalized linear model. We illustrate the framework with typical bird datasets from the Aquitaine region, south-western France. We show that, under some assumptions, our approach provides estimates that are more precise than the ones obtained from the dataset with a known sampling effort alone. When the opportunistic data are abundant, the gain in precision may be considerable, especially for the rare species. We also show that estimates can be obtained even for species recorded only in the opportunistic scheme. Opportunistic data combined with a relatively small amount of data collected with a known effort may thus provide access to accurate and precise estimates of quantitative changes in relative abundance over space and/or time

Dinard Herbarium: A Source of Information to Infer Temporal Changes in Seaweed Communities?

International audienc

Tourism in protected areas can threaten wild populations: from individual response to population viability of the chough Pyrrhocorax pyrrhocorax

International audienceMany protected areas are now faced with increasing pressure from visitors and tourism development. There is thus an urgent need for conservation biologists to evaluate the full impact of human disturbance not only on individual responses but also on the viability of protected populations so that relevant management measures can be proposed. We studied the impact of tourism on the rare and endangered chough Pyrrhocorax pyrrhocorax on a protected french island to assess the relationship between visitor pressure, bird individual behavior and fitness, and population viability. During 8 years, we monitored foraging behavior and estimated monthly juvenile survival using mark-recapture data. Population viability was examined under different tourism scenarios, using a stochastic individual-based model that incorporated the impact of visitor numbers on juvenile survival. In summer, the foraging probability of choughs was negatively correlated with the number of visitors. As a result, the time allocated to foraging during peak tourist season, adjusted to day length and prey availability, was 50% lower than expected. Juvenile survival rates were lowest in August, the peak tourist season, and varied significantly across years. August survival rate and therefore annual survival were negatively correlated with the number of visitors on the island in August and, except for a minor negative effect of rainfall, were not influenced by other environmental variables. Sthochastic simulations predicted a low probability of extinction of the protected population if the number of visitors remains constant in the future. However, short-term viability would be dramatically reduced if the current rate of increase in visitor numbers is maintained. We show that a relatively minor human-induced disturbance (e.g. scaring individuals away) has dramatic effects on population viability in a protected area, even when breeding individuals are not directly affected. This suggests that the full impact of tourism in protected areas may be overlooked, and has direct consequences for the assessment of sustainable levels of human distrurbance and the design of quantitative management options compatible with tourist activities in protected areas. We specifically emphasize the need for more integrative approaches combining research at individual and population levels