Phylum: Chordata - Class: Actinopterygii - Order: Salmoniformes - Family: Salmonidae
The gwyniad is a whitefish - a kind of land-locked herring. In Wales the only known population lives in the depths of Llyn Tegid (Bala Lake) in the Welsh Dee catchment. In recent years there have been concerns that eutrophication (over-enrichment by nitrates and phosphates running off the farmland around the lake) might threaten the survival of the gwyniad in this the largest natural lake in Wales.
Environment Agency Wales, Countryside Council for Wales - both now within Natural Resources Wales - together with Gwynedd County Council and others have been developing a plan to reduce the input of these damaging chemicals to the lake.
Another threat to this rare species is the ruffe (another freshwater fish species) that have been introduced to the lake recently; these bottom-dwelling perch-like fish are quite likely to be eating some of the gwyniad eggs. The rare vendace (Coregonus alba) of Bassenthwaite Lake, in Cumbria, are similarly threatened now that ruffe have been illegally introduced also to that upland lake.
The Environment Agency Wales hatchery at Maerdy has been rearing gwyniad from Llyn Tegid stock; the idea is to help maintain the natural population until the waters of Llyn Tegid can be restored to a satisfactory standard.