Régime et tactique alimentaires de la loutre (Lutra lutra) dans le Massif Central

Otter spaints were collected in 1991 on a seasonal basis in the river Chavanon catchment, a tributary of the river Dordogne, in central France. Small sized species (bullhead, three-spined stickleback, gudgeon and minnow) are the most numerous items in the diet: they account for more than 50% of the 3,148 identified preys. However, when expressed in relative biomass, their importance falls down (8 %). In fact, the brown trout, large cyprinid fish, birds and mammals make up the bulk of the diet. We found strong differences linked to the general habitat types and also seasonal ones. Frogs are mainly preyed upon during the spring whereas the snakes are exclusively taken in the summer and autumn months. Gudgeon and insects are also mainly summer and autumn preys. Perch and large cyprinid fish remais are more frequent during winter and even spring. The present results confirm the opportunistic way of predation of the otter and the fact that its hunting takes place more on the bottom and along the river banks than in the open water.