For anyone looking for the bird, some ID features to note are:
- more delicate head/bill structure than HEGU, heavier-bodied than most Kumlien's Gulls
- all black bill with just the slightest hint of paling at the base of lower mandible
- faint mask through the auriculars, more visible at some angles than others
- apparently all juvenile scapulars
- dark-centered tertials with marbled edging
- dark brown primaries (but not blackish) with thin pale fringes as seen on the folded wing
- short pinkish legs
In flight:
- dark outer webs of outer primaries contrast with pale inner webs ("Venetian blind" appearance)
- contrasting dark secondary bar
- dark tail band with marbling at bases of rectrices
- brown underwing linings contrast with whitish underside of flight feathers, with thin dark tips to outer primaries
juv Thayer's Gull
- NB
I see you're making good use of that camera. Nice flight shots of a nice find.
ReplyDeleteThanks Ben
ReplyDeleteThis is a nice blog Nick .
ReplyDeleteAndré Boven Holland Eu
http://birdingoldambt.blogspot.com/