Une population majeure de la très rare Grande Mulette Margaritifera auricularia (Spengler 1793) (Bivalvia : Margaritiferidae) dans le fleuve Charente (France)

During an environmental impact study concerning a scraping project on the Charente river, we discovered a major population of Giant Pearl Mussel Margaritifera auricularia (Spengler, 1793). We evaluate the population size to be over 20 000 individuals in the studied area from scuba diving counting, i.e. a lot more than the total number of Giant Pearl Mussels estimated worldwide. We discuss the characteristics of the Charente population, the methods used to estimate its size, the global conservation issues and the future management of the site.