Friday 25 November 2011

Olympic Gull: Glaucous-winged x Western Gull

Following on from the Western Gull pictures in the last post, here is a shot of an Olympic Gull taken along 17-mile drive in California. The Olympic Gull is a hybrid between Glaucous-winged and Western Gull, and according to this abstract has greater fitness than either parental form. I suppose F1 hybrids are well-known for their vigor in garden plant varieties. This individual matches those that are assumed to be a second generation hybrid, as the wing tips are only a shade darker than the upperparts but the bill is heavy and quite orange in colour. So, quite possibly, it is a Glaucous-winged x Olympic Gull hybrid...


As for this bird, photographed on Santa Monica beach, take your pick - but it definitely has a fair number of Glaucous-winged Gull genes in it. Whether it is a pure bird or not is beyond me... Any ideas?


http://onlinelibrary.wiley.com/doi/10.1111/j.0014-3820.2000.tb00721.x/abstract

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