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Le Touquet – Paris-Plage, France

Bech N.,CNRS Host-Pathogen-Environment Interactions Laboratory | Barbu C.M.,CNRS Host-Pathogen-Environment Interactions Laboratory | Quemere E.,French National Institute for Agricultural Research | Novoa C.,Center National Detudes Et Of Recherches Appliquees | And 2 more authors.

In Europe, the Quaternary is characterized by climatic fluctuations known to have led to many cycles of contraction and expansion of species geographical ranges. In addition, during the Holocene, historical changes in human occupation such as colonization or abandonment of traditional land uses can also affect habitats. These climatically or anthropically induced geographic range changes are expected to produce considerable effective population size change, measurable in terms of genetic diversity and organization. The rock ptarmigan (Lagopus muta) is a small-bodied grouse occurring throughout Northern hemispheric arctic and alpine tundra. This species is not considered threatened at a continental scale, but the populations in the Pyrenees are of concern because of their small population size, geographical isolation and low genetic diversity. Here, we used 11 microsatellites to investigate genetic variations and differentiations and infer the overall demographic history of Pyrenean rock ptarmigan populations. The low genetic variability found in these populations has been previously thought to be the result of a bottleneck that occurred following the last glacial maximum (i.e., 10 000 years ago) or more recently (i.e., during the last 200 years). Our results clearly indicate a major bottleneck affecting the populations in the last tenth of the Holocene. We discuss how this decline can be explained by a combination of unfavorable and successive events that increased the degree of habitat fragmentation. © 2013 Macmillan Publishers Limited. Source

Gaudry W.,Center National Detudes Et Of Recherches Appliquees | Gaudry W.,CNRS Biometry and Evolutionary Biology Laboratory | Said S.,Center National Detudes Et Of Recherches Appliquees | Gaillard J.-M.,CNRS Biometry and Evolutionary Biology Laboratory | And 4 more authors.
Journal of Mammalogy

The European roe deer (Capreolus capreolus) responds to environmental conditions that vary in time and space across its distributional range, generating many different space use patterns. To test the expectation that variation in movement patterns should track changes in environmental conditions, we used the net squared displacement metric to identify the factors shaping observed movement patterns of roe deer in the French Alps. Based on 5 years of data from 25 radiomonitored roe deer (54 individual-years), we found that movements were longest in spring and summer when the normalized difference vegetation index (NDVI) was higher and shortest in autumn and winter when NDVI was lower and snow cover was present. Roe deer displayed long displacements toward high elevations with gentle slope when the NDVI was higher. The higher quality food resources at higher elevations may have compensated for the energy costs of those movements. Contrary to previous studies on roe deer in mountain ranges, we showed that roe deer movements in the northern French Alps should be interpreted as within home range habitat selection (48 cases; 89%) rather than as partial migration because very few deer (6 cases; 11%) stabilized their activity in distinct home ranges across seasons. © 2015 American Society of Mammalogists. Source

Richard E.,University Claude Bernard Lyon 1 | Gaillard J.-M.,University Claude Bernard Lyon 1 | Said S.,Center National Detudes Et Of Recherches Appliquees | Hamann J.-L.,Center National Detudes Et Of Recherches Appliquees | Klein F.,Center National Detudes Et Of Recherches Appliquees

Many previous studies have pointed out that, when resources are limited, the potential for competition should be high among sympatric species that display overlaps in habitat and nutritional niches. However, reliable evidence of competition between red deer (Cervus elaphus) and roe deer (Capreolus capreolus) has not been yet reported for life history traits directly measuring performance such as body mass, reproduction, or survival. From long-term monitoring of deer populations in the reserve of La Petite Pierre (France), we measured the sex-specific responses of roe deer fawn body mass to changes in red deer density after accounting for possible confounding effects of date of shooting, climatic conditions, and roe deer density. As expected under the hypothesis of competition, red deer density in a given year had a marked negative influence on body mass of roe deer fawns born the same year and the following year. Fawn mass of roe deer males and females responded in similar ways to changes in red deer density. Our study provides the first evidence of a negative response of roe deer performance to high red deer density. © 2009 Springer-Verlag. Source

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