More Lesser-black Backed

Saturday, 27th July 2013

I was sitting around at the Obs this morning, as one is inclined to do here when things are quiet, my main sightings being a juvenile Cuckoo, a juv. Yellow-legged Gull and Manx and Balearic Shearwater. Caught off guard I'll admit by this '1st summer' L.b.b that by its generally dark appearance, contrasting rump and tail I took for another juv. michahellis (Yl)... until that it is, on inspection of photos on the camera screen, it was tactfully pointed out to me that this is (of course) a 2CY Lesser bb. 'Dooh', I hadn't even noticed the primary moult. Let's put it down to tiredness... although sheer sloppiness maybe the more plausible explanation.

OK so here we go then with Larus fuscus graellsii, 2 CY, '1st summer', briefly overhead at a distance. The bird show typical wing moult for the month / time of year (re. gull-research.org).


2nd CY Lesser black-Backed Gull (L.f.graellsii), Portland, 27th July 2013

2nd CY Lesser black-Backed Gull (L.f.graellsii), Portland, 27th July 2013

the innermost primaries 1-5 are new, 6 is growing, 7 missing, 8-10 old and worn / first generation

2nd CY Lesser black-Backed Gull (L.f.graellsii), Portland, 27th July 2013

2nd CY Lesser black-Backed Gull (L.f.graellsii), Portland, 27th July 2013

2nd CY Lesser black-Backed Gull (L.f.graellsii), Portland, 27th July 2013

It looks like innermost primaries 1-5 have been renewed, 6 is growing and 7 missing, whilst the old, worn juvenile primaries 8-10 remain. Secondary moult has also begun with the loss of at least one feather.

A similar aged Yellow-legged Gull would be in a more advanced stage of moult, having replaced most except primaries 1-2 which will be shed at around this time. More secondaries will have been lost too. The wings will therefore look somewhat shorter / stunted and ragged along the inner trailing edge. Please see this page of gull-research.org for a flight photo that nicely illustrates this.

Thanks Joe for your help and prompting this series of pictures. 'July, 2Y L.f.graellsii' is a new set for my files!

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