eric sourp

The ecological assessment of freshwater ecosystems necessitates to consider (i) the operational biological classification for defining a range of ecosystem alterations, (ii) operational biomonitoring tools fulfilling the requirements of the classification, (iii) ecological quality objectives to be preserved or restored. The development of this biomonitoring approach was illustrated by the study of the River Dore. Four biological qualities were defined

Over millennia, human intervention has transformed European habitats mainly through extensive livestock grazing. “Dehesas/Montados” are an Iberian savannah-like ecosystem dominated by oak-trees, bushes and grass species that are subject to agricultural and extensive livestock uses. They are a good example of how large-scale, low intensive transformations can maintain high biodiversity levels as well as socio-economic and cultural values. However, the role that these human-modified habitats can play for individuals or species living beyond their borders is unknown. Here, using a dataset of 106 adult GPS-tagged Eurasian griffon vultures (Gyps fulvus) monitored over seven years, we show how individuals breeding in western European populations from Northern, Central, and Southern Spain, and Southern France made long-range forays (LRFs) of up to 800 km to converge in the threatened Iberian “dehesas” to forage. There, extensive livestock and wild ungulates provide large amounts of carcass...

La montagne est un milieu vulnerable vis-a-vis du changement climatique comme l’indiquent deja les evolutions paleoclimatiques. Inedite a l’echelle des Pyrenees-Atlantiques, l’analyse de longues series homogeneisees de donnees sur la periode 1950-2013 indique une augmentation des temperatures de +0,2 °C a + 0,3 °C par decennie. Les projections climatiques etablissent la poursuite du rechauffement : a l'horizon 2071-2100, selon le scenario RCP 8.5, le rechauffement pourrait atteindre 4°C. En matiere d’enneigement, en depit d’une forte variabilite inter-annuelle et d’une tendance plus marquee a basse altitude, une perte de 2 a 3 jours d'enneigement par decennie est observee depuis le debut des annees 1980 ; les projections futures presagent d’une acceleration sensible a partir des annees 2050. Ces changements physiques ont des consequences sur la biodiversite et le fonctionnement des ecosystemes ainsi qu’un impact economique et social majeur. Les aspects operationnels de l’app...

The Pyrenees National Park is located in the western portion of the Pyrenees. It includes the majority of the peaks of height greater than 3000 m a.s.l. on the French side of the ridge. One region within this area (Cirque of Gavarnie) has been a listed as a UNESCO World Heritage site since 1997. Its geomorphological heritage is exceptional and the National Park would like to promote it. The aim of this paper is thus to propose an example of the assessment and promotion of geomorphosites at a regional scale. The assessment only concerns glacial and periglacial landforms and is based on three criteria: scientific, cultural, and use values. Potential geomorphosite assessment results are divided into two rankings: one is based on a “management score” and the other on a “tourism score”. The highest-priority geomorphosites for management and tourism use are objectively defined, by making use of a hierarchical ascendant classification method which reveals three main groups of homogenous ge...

The Pyrenean desman is a vulnerable mammal species endemic to Pyrenees and the northern Iberian Peninsula. The presence of this elusive species can be most easily detected by sampling its faeces. However, these faecal samples can be confused with those of other vertebrate species living in the same habitats. This study provides two easy and reliable methods for the identification of the Pyrenean desman faeces based on genetic analyses. The first one consists of a nested PCR and sequencing of a mitochondrial cytochrome

Un suivi de la population de Lézard de Bonnal Iberolacerta bonnali du Val d'Arrious (Vallée d'Ossau) a été mis en place dans le Parc National des Pyrénées. Ce suivi a permis de cartographier la distribution des Lézards pyrénéens de Bonnal et la zone de contact avec le Lézard des murailles Podarcis muralis, à partir de 2 010 m d'altitude. L'habitat du Lézard de Bonnal est localisé aux expositions les plus thermophiles comprenant les pelouses en gradin à Fétuque gispet, les zones d'éboulis, les dalles et falaises siliceuses ainsi que les blocs des éboulis frais et humides où persiste la neige, bordant le ruisseau d'Arrious. L'étude par capture-marquage-recapture a permis d'estimer la population de Lézards de Bonnal à 69 individus (54-99 individus à 95 %) pour 2 458 m², soit 281 lézards par hectare. L'étude du Lézard de Bonnal à Arrious a permis de réaliser un premier état des lieux de cette espèce et de valider une méthode de suivi de la population. D'autres stations seront suivies sur le même modèle afin d'établir un réseau de sites suivis sur le long terme. Summary-Monitoring of the population of the Pyrenean rock lizard Iberolacerta bonnali (Lantz, 1927) in the "Val d'Arrious" (Ossau Valley). A monitoring of the population of the Pyrenean rock lizard Iberolacerta bonnali in the Val d'Arrious (Ossau Valley) was established in the Pyrenees National Park. This monitoring allowed mapping the distribution of the Pyrenean rock lizard's as well as the contact zone with the common wall lizard Podarcis muralis, from the altitude of 2.010 m a.s.l upwards. The habitat of the Pyrenean rock lizard is restricted to the most thermophilous exposures, including Festuca eskia meadows, screes areas, siliceous slabs, and outcrops along with damp boulders and screes where the snow remains, along the stream of Arrious. A capture-mark-recapture study estimated the population size of the Pyrenean Rock Lizard's population size at 69 individuals (54-99 individuals at 95 %), for 2.458 m², i.e. a density of 281 lizards per hectare. The study of the Pyrenean rock lizard of Arrious allowed to make a first inventory of this species and to validate a monitoring method. Other sites will be studied following this protocol to establish a network of sites for long-term monitoring.