Wednesday, December 14, 2011

Hen Harrier

Female Hen Harrier, Fowlmere RSPB, 14th December 2011 © Brian Herdman
'Identification of ring-tail harriers can be a challenge, but this photo clearly shows five distinct primaries in the wing tip, identifying the bird as a hen harrier (four primaries are visible on Montagu's and pallid). Furthermore, this bird can be aged as an adult (i.e. at least one year old or more) because two ages of secondaries can be seen; a bird born this year should not have moulted any flight feathers, which would therefore all look the same age. See Forsman, D. (1999) The Raptors of Europe and the Middle East. Poyser, London.' Doug Radford who submitted the photo on Brian's behalf.

No comments: