Saturday, 21 January 2012

Immigrants from the NW and Poland

Nope, this isn't a Daily Mail style rant about London's growing population. After checking the river by our flat and then the lake at Burgess Park early doors with again no Med Gull, I headed to school for a few hours and the gulling had to be interrupted. While I was ramming the usefulness of different flood defence methods down my GCSE students' necks for their exam early next week, Kev J and Mick S had pulled a winger out of the bag at Crayford. A nice 2nd-winter Iceland Gull and, believe it or not, the first I'd seen this winter.

A couple of my shots showed a fairly obvious tail band but this really wasn't the case in the flesh, and highlights the danger of going off single images for some identifications. For some reason, this year's influx/wreck seem to have a disproportionate amount of this age.

So, having been able to enjoy a gull without a little bit of head scratching, it was back to Cross Ness where this bird was straight out from where I parked my car and on the Thames foreshore. What was immediately apparent was that it looked like a Caspian Gull and, a first for me, it was wearing a bit of bling.
Note the green ring with white writing on the right tarsus

Dobry wieczor!
Pretty confident that the green ring this bird was wearing meant that it'd be from Poland (yeah, home to mixed colonies of cachinnans, michahellis and argentatus!), I vaguely recalled that Dom had a ringed Casp from that neck of the woods a short while back at Rainham. So I texted him whilst Kev J, Mick S and I watched this eastern block of a bird. I was struggling with the wind to read the ring, as well as the bird being on the tideline being meaning its feet were in the water. But I managed to get '3P' as the last couple of digits before Dom's text arrived saying '355P'. Bang... nice stuff and it is the same bird that was superbly photographed by Dom here (note the totally different stance/jizz as today the bird was facing into a fierce blow) and Mick S will have much better shots at some point here from today. Aged as a near adult due to the fact that it had retained dark markings on the primary-coverts, these match up too with those on Dom's images.
Nice pale outer web to P10 with large white subterminal mirrors to both P9 and P10; also note the retained feathering on the primary coverts ageing it as a near adult/4th winter
Typically long-winged feel to the bird with a small beady eye even obvious in this flight shot
The bird was ringed in 2008, apparently in a mixed colony and unidentified at the time(!) like all pullus ringed in such situations - so this just shows the events we're dealing with when it comes to birds over here. By probability, you've got to assume that a lot of our Caspian-type birds are from the west/northwest of the range and the gene pool is rather diluted. Makes a change though for field birders to be telling ringers what their birds are... or at least trying to.

And dobry wieczor is good afternoon in Polish.

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