Crayfish Plague is recognised as an existential threat to the survival of the globally threatened white-clawed crayfish, Austropotamobius pallipes, which is the only crayfish species native to Ireland. Crayfish plague is a highly infectious lethal disease caused by a fungal-like organism, Aphanomyces astaci, which infects white-clawed crayfish and can cause up to 100% mortality. The latest information on the presence of crayfish plague in Ireland can be found here.