Wednesday 17 February 2016

Yellow-legged Gull intergrades

possible Yellow-legged Gull intergrade, Hyde Park (London, UK), 16th December 2006 - copyright Dave Appleton
(photo ID: 1567)

The Azorean form of Yellow-legged Gull (atlantis) is sometimes considered to be a distinct species (sometimes known as Azorean Gull), and appears to be a rare vagrant to north-west Europe with several credible claims from the UK and Ireland in recent years.  The individual shown here showed many features consistent with this taxon but some observers felt that not everything was quite right.  Specifically they felt that the tone of the upperparts was a bit too much like michahellis Yellow-legged Gull and the structure was not as it should be.  It is possible that it was an odd atlantis, and it is possible that it was a Yellow-legged Gull originating from one of the other Atlantic island populations, but perhaps an intergrade or hybrid between the two might be the most satisfactory explanation.

possible Yellow-legged Gull intergrade (same bird as in photo ID 1567 above), Hyde Park (London, UK), 16th December 2006 - copyright Dave Appleton
(photo IDs: 1567-1570)

Yellow-legged Gull Larus michahellis  
Azorean Gull Larus (michahellis) atlantis

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