SPAANS AL (1962) Observations of possible hybrids of Redpoll Carduelis flammea and Arctic or Hoary Redpoll Carduelis hornemanni on the island of VUeland. LIMOSA 35 (3): 272-274.

In the first week of January 1962 various observers reported the occurrence of at least six Redpolls on the island of Vlieland. These birds were conspicuous by their paleness of plumage and their remarkable tameness. They were at first cons:dered to be Hoary Redpolls, but as they had the rump not pure white, but greyish white instead, and as there was some variation in the extent of the broad white feather edges on the scapulars and the whiteness of the under parts, the birds could best be described as clear intermediates between Carduelis flammea flammea and Carduelis hornemanni exilipes. In view of the fact that apparent signs of hybridization of these forms of Redpolls are known from northern Scandinavia, these birds were considered to represent a flock of possible hybrids of flammea and exilipes. Unidentified Redpoll Carduelis cabaret/flammea Arctic Redpoll Carduelis hornemanni

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