Urban Stress
Galloping urbanization is a major cause of the disappearance and homogenization of natural landscapes. We study the impacts of urban life through sentinel species of this environment (house sparrows, blackbirds, chickadees). These different species have to cope with multiple disturbances such as noise, light and atmospheric pollution. They also have to cope with a shortage of nesting cavities and modified diets (fewer insects, junk food, etc.). We show that these animals can cope with these constraints and adapt to the urban environment. Nevertheless, this adaptive capacity remains limited and these animals present higher levels of stress and accelerated ageing compared to rural bird populations. Our results partly explain the current collapse of common bird populations, as in the case of the house sparrow.
Degradation of agricultural landscapes
The current intensification of agricultural practices is a major cause of habitat degradation and biodiversity loss. These effects are particularly strong in Reptiles and Amphibians, which are characterized by low mobility and dependence on specific environments. We have launched a “Bocage & biodiversity” programme in the Deux Sèvres in collaboration with the ONCFS and a network of farmers. Our work highlights the positive relationship between a preserved bocage landscape (networks of hedges, ponds and small woodlands) and the specific richness of reptiles and amphibians. The presence of species obtained by modelling is modelled on the bocage landscape of the Deux Sèvres. We have also demonstrated the importance of the quality of the microhabitats: hedge structure and breeding ponds. Maintaining landscapes that are compatible with biodiversity requires action at the farm level.
Stress and migration
In the space of a century, the Greater Snow Goose has gone from being an endangered species to a superabundant one. The population dynamics of the snow goose are closely dependent on the environment encountered along the flyway. The quantity and quality of available food resources will affect the body condition of the geese upon arrival in the high Arctic, a key factor governing reproduction. The drastic change in population size is mainly due to human activities: limitation of hunting and changes in agricultural practices: arrival of maize in the 1970s. From now on, the conservation objective is to limit this population in order to avoid overgrazing of the tundra. Our team is interested in stress physiology and fattening modulation in this species in order to assess how this type of constraint, encountered on migratory stopovers, can affect breeding decisions in the Arctic.