SWAAB J, MARLE JG VAN & MEETHP (1971) Short announcements: Observation of a Black Guillemot Cepphus grylle. LIMOSA 44 (3): 191-191.

From February 7th till 15th, 1971 a Black Guillemot Cepphus grylle has been observed by several persons on the island of Texel and on February 20th 1971 on Terschelling; according to the description probably the same bird. This is the 12th confirmed observation for the Netherlands. Black Guillemot Cepphus grylle

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