Fédération Nationale des Centres d'Initiatives pour Valoriser l’Agriculture et le Milieu Rural

The western capercaillie Tetrao urogallus , hereafter capercaillie, is the largest galliform bird present in the boreal and montane forests of the Western Palearctic. Precise and accurate methods for estimating the number of individuals and/or their densities are crucial for the proper management of its free‐ranging populations. However, obtaining reliable estimates of the abundance of populations of wild species and, particularly, of birds is not a simple task. In the case of lek‐mating birds such as capercaillie, surveys are traditionally based on lek counts, that is, counts of calling males present in their mating areas: the leks. This study was carried out on the Pyrenees at six capercaillie leks where two different lek counting approaches were performed: hide‐based and walk‐based. The results were compared with those obtained from an estimate of minimum population size (MPE) derived from genotyping all faeces samples found in the lek area, and with a population size estimate derived from a genetic mark‐recapture model () of each capercaillie lek. The results of were used to estimate the detection rate ( D ) of both lek count approaches. Our results show that traditional lek counts do not detect all male capercaillies since the detection rate was 0.34 (95% CI: 0.26–0.43) for hide‐ and 0.56 (95% CI: 0.43–0.68) for walk‐based lek counts. Our results suggest that the walk‐based lek counts were more efficient than the hide‐based ones, providing more accurate results compared to the estimate. The combination of non‐invasive sampling with genetic mark‐recapture model was found to be the most reliable method for obtaining the of leks given that traditional lek counts underestimate the number of capercaillie and, furthermore, can cause disturbance to the species at these sites.

Understanding colonization of new habitats and ecological successions is key to ecosystem conservation. However, studies on primary successions are scarce for reef-building corals, due to the rarity of newly formed substratum and the long-term monitoring efforts required for their long life cycle and slow growth rate. We analysed data describing the diversity, structure and demography of coral assemblages on lava flows of different ages and coral reefs at Reunion Island, to evaluate the strength and mechanisms of succession, and its agreement to the theoretical models. No significant differences were observed between the two habitats for most structure and demographic descriptors. In contrast, species richness and composition differentiated coral reefs from lava flows, but were not related to the age of the lava flow. We observed a strong dominance of Pocillopora colonies, which underline the opportunistic nature of this taxa, with life-history traits advantageous to dominance on primary and secondary successional stages. Although some results argue in favor of the tolerance model of succession, the sequences of primary successions as theorized in other ecosystems were difficult to observe, which is likely due to the high frequency and intensity of disturbances at Reunion, that likely distort or set back the expected successional sequences.

Changes in agricultural practices have reshaped agricultural landscapes and triggered a drastic decline in spatial and temporal heterogeneity leading to changes in habitat quality and food resources for birds. However, the precise relationships between landscape changes, spatial and temporal heterogeneity, and habitat preferences in response to those changes remain poorly known.We investigated patterns of habitat selection and causes for changes over the years 1997–2017 for the gray partridge Perdix perdix, an iconic farmland species which has experienced a severe decline since the 1950s. Using a long‐term (1997–2017) dataset collected over 435 km2, we modeled relationships between annual land‐cover maps and partridge sightings over 17 5‐year moving windows, assessing the effects of landscape metrics, the strength of the relationships, and the dynamics of habitat suitability.We detected a shift in gray partridge habitat preferences over time, toward more risky habitats. Avoidance of predator reservoirs (woodlands and buildings) has weakened, and selection of human infrastructure, such as roads and tracks, has increased. Since 1997, the mean size of suitable patches has also decreased by about 26%.We have interpreted these changes in habitat selection as being the result of decreasing habitat quality and the increasing prevalence of captive‐reared birds, currently released in their thousands in the study site.Synthesis and applications. The gray partridge has not adjusted well to changes in farming practices, and the low, still decreasing, population density suggests that it is not sustainable, despite local initiatives and the investment in captive‐bird releases. We emphasize that efforts must be redirected toward habitat improvement to restore the density of refuge cover, insects, and seeds in the landscape, hunting management to ensure self‐sustainable populations and massive releases of high‐quality birds. Only integrated local management, involving hunters, farmers, gamekeepers, and scientists can ensure the recovery of this species.

Studies of animal ecology can benefit from a quantified understanding of eco‐physiological processes and, in particular, of the physiological responses in free‐ranging animals to potential stressors. The determination of fecal cortisol metabolites as a noninvasive method for monitoring stress has proved to be a powerful tool. High‐performance liquid chromatography coupled with tandem mass spectrometry (HPLC‐MS/MS) has emerged as the most accurate method for avoiding problems related to the nonspecificity of immunoassays. In this study, we optimize and validate a reliable method using HPLC‐MS/MS for quantifying 11‐ketoetiocholanolone (11‐k), a representative fecal cortisol metabolite in ruminants. An appropriate extraction and purification procedure was developed taking into account the complex nature of feces. The final extract obtained was then analyzed with HPLC‐MS/MS using a quadrupole‐time‐of‐fly (QTOF) tandem mass spectrometer with an electrospray ionization interface operating in positive mode, which allowed an unequivocal determination of the metabolite due to its accurate mass capabilities. After rigorous optimization of both sample extraction and the HPLC‐QTOF parameters, making use of feces from free‐ranging Iberian ibex, ideal conditions were established. Matrix‐matched standards were used to calibrate the method. The limit of detection and quantification was 13‐ and 40‐ ng/g, respectively. The validation of the method was performed with recoveries in the range of 85–110%, a figure much higher than the 60% obtained with the previous extraction methods used in our laboratory, and with relative standard deviations (RSDs) no higher than 15% for the complete analytical procedure, including extraction and analysis. The time required for the fecal 11‐k analysis was greatly reduced in comparison with the previous work carried out in our laboratory. This is the first time that QTOF mass detection coupled with HPLC has been validated for 11‐k quantification in feces from free‐ranging ruminants such as Iberian ibex. Given the high selectivity and sensitivity attained, our method could become a useful tool for noninvasive stress quantification in ruminants.

Les avis en ligne sont devenus l’une des plus importantes sources d’information des consommateurs quoique leur crédibilité soit sujette à caution en raison de l’anonymat de l’Internet. Cet article se fonde sur une revue de la littérature pour préciser l’impact de deux variables antécédentes de la crédibilité d’un avis en ligne : le profil de l’auteur et la qualité des arguments. Il s’intéresse ensuite à une variable modératrice des relations respectives entre ces deux variables et la crédibilité d’un avis en ligne : l’implication. Il propose ensuite trois modérateurs alternatifs : l’expertise, le scepticisme et le besoin de cognition du consommateur. L’intérêt théorique de cet article réside dans la proposition d’un modèle intégrateur. L’intérêt managérial de ce papier est pour les sites hébergeurs : il leur permet de mieux comprendre leurs lecteurs.

Les bourses et les subventions accordées par trois fondations distinctes en faveur de la recherche sur l’art des États-Unis représentent chaque année un soutien de quinze à vingt millions de dollars. Ces financements privés ont contribué pour une large part à l’évolution et à la maturation de cette discipline. Les trois organisations qui distribuent cet argent – essentiellement les Luce, Terra et Wyeth Foundations – sont très différentes en ce qui concerne leurs fondateurs, leurs priorités, leurs dimensions, leur organisation administrative et leur impact. Quelles sont les répercussions de ces investissements privés massifs dans le domaine de l’histoire de l’art aux États-Unis ? Les priorités de ces fondations sont-elles devenues les priorités de cette discipline ?

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