Monday, December 5, 2011

juv THAYER'S GULL, Windsor Landfill

My first landfill visit of the season was highlighted by a crisp juvenile THAYER'S GULL among 1000+ LWHGs working the trash piles. Interestingly it was the only uncommon gull present...not a single Iceland, Glauc or LBBG. It's a small landfill that can be very hit or miss, but has a track record in recent years of pulling in some nice birds (two Slaty-backs and a few Thayer's). Let's hope this is the start of a productive season.

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

3 comments:

  1. I see you're making good use of that camera. Nice flight shots of a nice find.

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  2. This is a nice blog Nick .

    André Boven Holland Eu

    http://birdingoldambt.blogspot.com/

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