Saturday, 18 May 2013

More Gull Action at Topsham Rec

17th May 2013 - Topsham

The Bonaparte's Gull hasn't been seen since Wednesday and frankly I'm hoping it might have moved on. I have sympathy for the few people still turning up to see it but I admit it'll be nice to have the place to myself again.

Perhaps as consolation, a first summer Little Gull has dropped in a couple of times, surprisingly an addition to my list for the site and the first one I've seen for a few years. The local Black-headed Gulls, delighted to have found something below even them in the gull pecking order, gave it a bit of a hard time and it didn't stay long. I wish they'd gang up and clear out the 'plastic' waterfowl as well - the 'farmyard' ducks and Mute Swans (sorry, I just don't care for them) and there were even a pair of Bar-headed Geese a couple of weeks back...don't get me started.

Meanwhile, some proper birds - further up the river, where the big gulls bathe and preen at low tide, things got interesting. I found this bird with the usual Herring Gulls.

I've become suspicious of apparent Yellow-legged Gulls and here's why.

Out of the water the bird showed a nice pair of pink legs; there was a hint of yellowish I think but nowhere near the bright yellow of a michahellis. So how about an argentatus Herring Gull? Maybe the grey is a little too dark but the wing pattern settles it.

There are two big white mirrors on P9 and P10, a lot of black on P8-10, black bar on P5 and obvious white 'moons' behind the black on P5-7. So, no pale tongues on outer primaries, no solid white tip to P10 and the black on P5 together fairly comprehensively rule out argentatus.  It also doesn't look like a michahellis with abnormally coloured legs since the large mirror on P9 and the white moons are also wrong. Reluctantly, because it's something of a cop-out, I've got to say It's almost certainly a hybrid, presumably with the genes of argenteus Herring and graellsii Lesser Black-backed. Looking closely at the primary pattern I'm pretty sure this bird is one I saw here on the 28th April. This is the second apparent hybrid at this spot this year - and I've only seen two 'safe' Yellow-legged Gulls in that time.

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