© A. R. Dean

A 2W Yellow-legged Gull with a similarly-aged Lesser Black-backed Gull (and an adult Black-headed Gull to the rear). The YLG appears more advanced than the LBBG and would appear even more so in comparison with a 2W Herring Gull in late October. Note the relatively clean and predominantly white head, foreneck and breast, with evident streaking confined to the lower hindneck. The uniformly grey shade of the mantle and scapulars creates a 'saddle' and this colour extends to a number of newly replaced median coverts and a few lesser coverts. The shade of grey is paler than the (smaller number) of replaced mantle and scapular feathers of the LBBG but is darker than would be shown by a British argenteus Herring Gull, though nominate Scandinavian argentatus Herring Gulls may show a comparable shade. The latter in particular would show few uniformly grey feathers in its upperparts in late October. The inner greater coverts of the YLG are strongly barred (if visible the outer greater coverts would be plain in comparison). The median and lesser coverts remaining to be replaced are largely hidden here but it can be seen that they have a rather coarsely 'spotted' appearance. The second-generation tertials still have extensively black centres (as in 1W) but show a broader white tip bearing a narrow anchor-mark. This pattern converges with the 2W LBBG but is distinct from the more variegated, notched pattern in a similarly-aged Herring Gull.