The preservation of the boreal lynx (Lynx lynx carpathicus) represents a major stake for the preservation of biodiversity in France. The survey - by correspondents of the Wolf-Lynx network like here Gilles Moyne from the ATHENAS center - of the presence of the species at the national level localizes individuals in an extensive and continuous manner. Compiled with the reports of attacks on domestic herds and deaths by collision or poaching, it makes it possible to establish a detection map of the presence of the species.