Melanitta nigra nigra
In Mathew's day a not rare winter visitor; now to be seen at all times of the year. Rafts (up to 400) summer in St Bride's Bay and Carmarthen Bay, also off Strumble Head and St David's Head. It may thus be more numerous in summer than in winter.
R.M.Lockley, G.C.S.Ingram, H.M.Salmon, 1949, The Birds of Pembrokeshire, The West Wales Field Society