Biodiversité

La géophonie rassemble les sons issus des quatre éléments d’Empédocle : la terre, l’eau, le feu et le vent.

Species distribution models (SDMs) are statistical tools that relate species observations to environmental conditions to retrieve ecological niches and predict species' potential geographic distributions. The quality and robustness of SDMs clearly depend on good modelling practices including ascertaining the ecological relevance of predictors for the studied species and choosing an appropriate spatial resolution (or ‘grain size').

Au sommaire notamment :

.A bird in the hand: Global-scale morphological trait datasets open new frontiers of ecology, evolution and ecosystem science. Joseph A. Tobias

Les indicateurs sont organisés selon les 6 critères de gestion durable des forêts européennes, dits critères d'Helsinki - du nom de la conférence où ces critères ont été adoptés.

The recent recovery of large carnivores in Europe has been explained as resulting from a decrease in human persecution driven by widespread rural land abandonment, paralleled by forest cover increase and the consequent increase in availability of shelter and prey. We investigated whether land cover and human population density changes are related to the relative probability of occurrence of three European large carnivores: the grey wolf (Canis lupus), the Eurasian lynx (Lynx lynx) and the brown bear (Ursus arctos).

The ongoing recovery of terrestrial large carnivores in North America and Europe is accompanied by intense controversy. On the one hand, reestablishment of large carnivores entails a recovery of their most important ecological role, predation. On the other hand, societies are struggling to relearn how to live with apex predators that kill livestock, compete for game species, and occasionally injure or kill people. Those responsible for managing these species and mitigating conflict often lack fundamental information due to a long-standing challenge in ecology: How do we draw robust population-level inferences for elusive animals spread over immense areas? Here we showcase the application of an effective tool for spatially explicit tracking and forecasting of wildlife population dynamics at scales that are relevant to management and conservation.

Il a longtemps été supposé que les espèces rares contribuaient faiblement au fonctionnement des écosystèmes. Des études récentes ont cependant remis en cause cette hypothèse, la notion de rareté ne recouvrant pas seulement l’abondance ou l'étendue géographique des espèces, mais aussi l’originalité de leurs rôles écologiques. Ces espèces aux fonctions uniques étant irremplaçables, il est désormais fondamental de comprendre leurs caractéristiques écologiques, de cartographier leur distribution et d’évaluer leur vulnérabilité aux menaces actuelles et futures.

Approaches to understanding change in plant function due to climate change often assume a fixed response: a given amount of climate forcing will cause a given amount of change in the measure of interest. Our study shows that this will not be the case for phenology. Effects of warming will be context dependent and vary with natural climate variability. Experimental warming in early, warm springs led to a greater advance of leafing, but more variation among species.

Assessing the pathways by which alien species are introduced is essential if we are to identify potential risks and evaluate management decisions. Intentional introductions are responsible for the introductions of millions of animals throughout Latin America. We explore: (1) the relative role of several intentional introduction pathways (hunting, feeding, fur, biological control, the pet trade and others) in the general context of introductions of alien species; (2) the relative importance of the intentional pathways across the different taxa; (3) similar patterns as regards the composition of alien species across countries, (4) the underlying factors that drive the richness of alien species in Latin America, and (5) the potential impacts of alien species on the region. According to our results, 69 species of mammals and 62 species of birds were introduced into Latin America by means of intentional pathways...

To understand how functional traits and evolutionary history shape the geographic distribution of plant life on Earth, we need to integrate high‐quality and global‐scale distribution data with functional and phylogenetic information. Large‐scale distribution data for plants are, however, often restricted to either certain taxonomic groups or geographic regions.

Durant des millions d'années, les poissons d'eau douce évoluaient de manière isolée dans leurs continents respectifs. Jusqu'à ce que le déplacement massif des espèces par les sociétés humaines rebattent les cartes, selon une étude parue vendredi 17 novembre.

Area of Habitat (AOH) is “the habitat available to a species, that is, habitat within its range”. It complements a geographic range map for a species by showing potential occupancy and reducing commission errors. AOH maps are produced by subtracting areas considered unsuitable for the species from their range map, using information on each species’ associations with habitat and elevation.

Primary forests, defined here as forests where the signs of human impacts, if any, are strongly blurred due to decades without forest management, are scarce in Europe and continue to disappear. Despite these losses, we know little about where these forests occur. Here, we present a comprehensive geodatabase and map of Europe’s known primary forests. Our geodatabase harmonizes 48 different, mostly field-based datasets of primary forests, and contains 18,411 individual patches (41.1 Mha) spread across 33 countries. When available, we provide information on each patch (name, location, naturalness, extent and dominant tree species) and the surrounding landscape (biogeographical regions, protection status, potential natural vegetation, current forest extent).

Recent declines of many European bird species have been linked with various environmental changes, especially land-use change and climate change. Since the intensity of these environmental changes varies among different countries, we can expect geographic variation in bird population trends. Here, we compared the population trends of bird species among neighbouring countries within central Europe (Czech Republic, Denmark, Germany, Switzerland) between 1990 and 2016 and examined trait-associations with population trends at both national and international scales. We found that Denmark had the highest proportion of declining species while Switzerland had the lowest.

Il y a cent trente-deux espèces de plantes qui ne poussent qu’en Corse. L’Atlas qui est vient de sortir aux éditions Albiana propose une présentation détaillée de 500 des 2300 espèces présentes en corse et notamment de celles qui sont endémiques.

Identifying species that are both geographically restricted and functionally distinct, i.e. supporting rare traits and functions, is of prime importance given their risk of extinction and their potential contribution to ecosystem functioning. We use global species distributions and functional traits for birds and mammals to identify the ecologically rare species, understand their characteristics, and identify hotspots.

Il semble que certains animaux voient leur taille diminuer dans les zones où la température augmente. Stratégie d’adaptation ou conséquence du changement climatique  ?

De nombreuses espèces sont aujourd’hui en déclin, même si parfois, la vie semble s’adapter : certaines espèces sont capables de décaler leur domaine vital vers les pôles pour y chercher la fraîcheur, d’autres modifient leurs habitudes, et certaines deviennent même… plus petites ! Serait-ce une stratégie pour moins souffrir de la chaleur ou simplement une conséquence subie du changement climatique ?

Au cours de ma thèse sur ce sujet, je me suis appuyé sur les théories développées en biogéographie...

According to the competitive exclusion principle, species with low competitive abilities should be excluded by more efficient competitors; yet, they generally remain as rare species. Here, we describe the positive and negative spatial association networks of 326 disparate assemblages, showing a general organization pattern that simultaneously supports the primacy of competition and the persistence of rare species. Abundant species monopolize negative associations in about 90% of the assemblages. On the other hand, rare species are mostly involved in positive associations, forming small network modules.

Le parc national de la Vanoise a entrepris un suivi par localisation GPS de la population des bouquetins des Alpes sur son territoire. Cette année des opérations de capture ont donc été réalisées par les équipes du Parc pour équiper des bouquetins de collier GPS. Ceux-ci vont permettre de mieux connaître les déplacements des animaux et de réaliser un point sanitaire sur les populations du parc national. Cette étude s’inscrit dans le cadre du programme de coopération transfrontalière « ALCOTRA LEMED (du Leman jusqu’à la Méditerranée) IBEX ».