Motacilla alba yarrellii

Numerous breeder, and nesting on most islands (Ramsey, Skomer, Skokholm, Caldey, not Grassholm).  Roost of 600-1000 in gorse at Martletwy, Jan-March 1935.  Also regular and numerous autumn passage migrant.

R.M.Lockley, G.C.S.Ingram, H.M.Salmon, 1949, The Birds of Pembrokeshire, The West Wales Field Society

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