Thursday, 9 December 2010

More adult Common Gull variation

Here are a few more pictures of adult, or near adult, Common Gulls taken in the garden over the last few days.

First off, here is a bird with unusual white and black markings in the outer greater coverts of the right upperwing (I didn't see the left). Could this be a sign that it is in its third calendar year?

Next some birds with extended black leading and trailing edges on P8–6. On the first bird the black leading edge of P7 is very clear on the left upper wing.

On this bird the extended black trailing edge is clear on the right underwing.

The first two following pair of images show the difference to the overall look of the under wing tip pattern with and without these black extensions on the trailing edge of the primaries. The white tongues on the second bird end abruptly rather than in points. Note also the strong bill ring on the first bird.

Finally, here is an unfortunate variation – a completely tail-less individual which flew past in a weirdly buoyant manner during my morning coffee break. Maybe the victim of a predation attempt or possibly lost its tail feathers after freezing to some ice, I'm going to keep an eye out for this one over the next few days.

No comments: