Recent acute crayfish mortality reveals Aphanomyces astaci presence in Bosnia and Herzegovina

Abstract Although the introduction of the crayfish plague pathogen Aphanomyces astaci to Europe is responsible for substantial declines in native crayfish populations throughout the whole continent, its presence has never been officially confirmed in many European regions, including most of the Balkan Peninsula. We demonstrate that the recent crayfish mortality observed in Bosnia and Herzegovina (Mostarsko blato karst field, Neretva river drainage) was caused by A. astaci . The causative strain is known only from European crayfish, indicating that A. astaci poses a threat to native species in this region, even in the absence of its main vectors, the North American crayfish.