Ongoing stormy weather and leaden skies with frequent wintry showers saw us birding from the car with the obvious highlight being reacquainting ourselves with flight views of the returning Kumlien's/Thayer's Gull at Uyeasound. Hopefully we will see it both on the deck and on a brighter day soon... No adjustments apart from cropping to the following images:
3rd cycle Kumlien's/Thayer's Gull at Uyeasound
Pro-Thayer's features as I see them include the tail pattern (similar to that of a 2nd cycle), the darkness of the outer webs and narrow paler inner webs of the outer primaries, dark-centred tertials, small mirror on p9 restricted to the inner web, its small white primary tips and heavily-blotched hindneck. Furthermore, the slight contrast between adult-like (blacker) p5 & p6 and slightly greyer p7 - p10 are a close match to the individual 32A.28 (Ayyash 2024).
3rd cycle Kumlien's/Thayer's Gull at Uyeasound
Ideally for Thayer's, perhaps the dark grey outer web of p7 shouldn't fall short of the primary coverts and the outer web of p10 shouldn't become paler distally?
3rd cycle Kumlien's/Thayer's Gull at Uyeasound
For 3rd cycle Thayer's Gull Ayyash (2024) describes 'head markings sometimes extend well below the neck and onto the lower breast, upper belly, and flanks.' But, for Thayer's, perhaps ideally it should be showing a darker underside to p10 (Adriaens et al. 2022)?
