Black-headed Gull, Qatar, Feb-Mar 2013 (1 Viewer)

I've seen big size difference between UK BHGs - though in that case it was an unusually small one


http://www.birdforum.net/attachment.php?attachmentid=16684&d=1108375672

Does optical size illusion not render the bird at the rear of a photo bigger than the one in the foreground? Same situation with Jane's link

on mine, the front bird was tiny.... I had to knock my little gull count back by one when I saw the the photo!

Greatly appreciate all the comments (and good humour).

Small gull species do of course tend to show less apparent size differentiation than large gulls. By definition they are smaller, hence the variance is always likely to be smaller empirically.

But this bird was certainly a stand-out individual, hence my posting. I tried to post photos which represented the size comparison against other gulls as was perceived in the field.

Perhaps there is an overall tendency (is 'cline' too strong a word?) for BH Gulls to become larger farther east. And at what point do they become sibiricus? Much farther east of the Arabian Gulf of course.

So I guess we put down the strangely blackish head patterning (yet to develop into a fully summer plumaged hood), robust bill and overall size, plus that exagerrated wing pattern as simply variation within L. ridibundus. And with L. r. sibiricus being so contentious, I guess it's hardly likely there is any racially-based variation acceptable west of China.

Thanks again. Always enlightening!

KenM said:

Well Neil...after 250 views!...we don't seem to have advanced much...with no other contributions forthcoming?..We could name it Chroicocephalus ridibundus orientalis large-us.

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Thanks for your persistence Ken B

KenM said:

Jane..perhaps some parties feel "uncomfortable" commenting on that..
which they have no prior reference of...for fear of appearing "less than?"

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I am not quite sure what you are talking about here and if you are referring to me, but anyway, I can assure you that I have seen many sibiricus in the field, and that I have carefully looked at them and photographed them. They did not impress me much in the field - they basically looked like any Black-headed Gull. Even now, when I check my photographs, I do not see any clear differences.

KenM said:

If nothing else, the size disparity (quite evident) should be prompting more questions, than are being currently asked, and the comment that this bird might be representative of the race sibericus..might be worth more discussion...after all..isn't that the "functioning" purpose of a forum?

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Just because one bird is slightly bigger than the other, does not mean that it has to be a mega rarity from the other side of the planet.