OLSTHOORN JCM (1986) Short contributions: Guillemot Uria aalge lacking part of webs between toes. LIMOSA 59 (2): 93-93.

Atlantic Murre Uria aalge On 22th May 1978, a presumably adult Guillemot was photographed on the Isle of May (Scotland) which lacked webs between the middle and outer toes of both feet (fig. 1). None of the contacted experts had seen this before. It is suggested to be a genetic aberration

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