Snowdonia hawkweed  (Hieracium snowdoniense)

The decline of this species may have been the result of a prolonged period of overgrazing, particularly the massive increase in sheep grazing in the Welsh mountains during the last 50 years. Sheep find many species of hawkweed extremely palatable, and in accessible areas they may have grazed Snowdonia hawkweed to extinction. An alternative explanation has been proposed for the extremely precarious status of this plant, namely the increase in acid rain, which is likely to have caused soil acidification (3). As this hawkweed is now so exceptionally rare, collection by botanists may be a new and potentially disastrous problem. Chance events such as rock-falls may also pose a risk to this hawkweed; as there is just one known remaining plant, the species is inherently more vulnerable to such unpredictable occurrences (3).

The current location and all historic sites for this hawkweed are afforded a high degree of protection as they are Sites of Special Scientific Interest (SSSIs), and occur in the Snowdonia National Park and the Yryri Special Area of Conservation (3). Encouragingly, sheep grazing has recently been eliminated from Cwm Idwal National Nature Reserve in order to aid the local wildlife; hopes are that this move will help the Snowdonia hawkweed to recover (2). Furthermore, seed has been collected in order to start an ex-situ population at the National Botanic Garden of Wales; seedlings are being cultivated at present. Further survey work has been proposed, which will aim to discover further wild plants, and, if establishment of a strong ex-situ population is successful, a re-stocking programme may be feasible (3). These urgent conservation measures aim to reclaim this acutely endangered and unique plant from the very brink of extinction.