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| Scaup x Tufted Duck 13/3/11 |
The above Scaup x Tufted hybrid was on Eglwys on Sunday. I've been reading a little bit about the various wing patterns, both upper and under, and thought it was a good opportunity to show comparison shots.
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| Scaup x Tufted Duck 13/3/11 |
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| Lesser Scaup 6/3/11 |
The upperwing pattern seems quite straightforward with the white of the Lesser Scaup confined to the secondaries, becoming grey in the primaries. The hybrid showing a Scaup like pattern with extensive white wing-bar almost reaching the outer primaries.
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| Lesser Scaup 16/2/11 |
An article I have read Garner, M. 2002 Identification extra: Lesser Scaup - the underwing. Birding World 15:506-508. looks at underwing features. I've included some shots above and below that seem to show that there are variations in this feature and/or they depend very much on the lighting conditions on the particular day.
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| Scaup x Tufted Duck 13/3/11 |
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| Lesser Scaup 6/3/11 |
The article suggests that the axillaries and the lesser and median underwing-coverts should appear white, on Lesser Scaup. This is accentuated by the greyer/darker border produced by the greater underwing-coverts and flight feathers. I'm guessing that the prominence of this feature depends a lot on the light at the time of viewing.
The underwing on the Lesser Scaup (6/3/11) appear mainly grey with the wing-bar showing through well in certain lights, in some cases showing the upperwing pattern as well as you would expect given a view from behind. The same article suggest that in a hybrid bird would probably show a pale underwing due to the fact that all the candidates ie Pochard, Scaup and Tufted Duck, show pallid underwing.
It would be interesting to see some shots, especially the underwing, of the drake Lesser Scaup in Cardiff to see how it compares with these birds.
