sentences:  Not only does the invading species fight for food resources, but it also carries crayfish plague, to which the native species has no immunity.The Afon Lwyd Trail is shared-use path running from Blaenavon Ironworks in the north via Pontypool to Cwmbran in the south.The path initially follows the Monmouthshire and Brecon Canal followed by a section on the former Pontypool to Blaenavon railway.