Identification of Siberian and other forms of Lesser Whitethroat

Reports of the central Asian (Siberian) race of Lesser Whitethroat Sylvia curruca blythi have increased in Britain and Ireland over the past decade or so. The reasons for this are unclear, but the trend follows the increased westward vagrancy of other Siberian passerines, which have now become a regular feature of late autumn (Baker 1977; Elkins 1983; Howey & Bell 1985). It

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