Crayfish plague (Aphanomyces astaci) is a devastating fungal-like pathogen that has severely impacted native crayfish populations in the UK, particularly the endangered white-clawed crayfish (Austropotamobius pallipes). Introduced via invasive signal crayfish (Pacifastacus leniusculus), which are carriers of the disease, the pathogen spreads rapidly in freshwater systems, causing mass mortalities among native crayfish. The pathogen disrupts ecosystems by decimating populations of a keystone species, making its detection and management a critical conservation priority.
