Wednesday 21 March 2012

3cy Black-headed Gull

It's not uncommon to identify Med Gulls in their 2nd-winter in the field on the basis of their obvious dark primary markings. However, I've not exactly been calling every 2nd-winter Black-headed Gull that I see as such. But they're pretty doable so long as you get a good view. And when you've got one in the hand that's certainly the case. Photos from last Saturday at the tip.
slightly dark-tipped bill compared to adults in the same catch; less extensive summer plumage on head compared to most adults. However, this feature possibly more moult timing rather than age related? Though a recent Dutch Birding article on long-lived B-h Gulls suggested that lack of full summer plumage could also be a feature of senility.

Note the subtle black markings in the primary coverts as well as the obvious black mark on the alula

Very obvious dark markings in secondaries as well as the inner webs of the inner primaries
Probably nothing special here for you ringers, but for a field birder like me it's always good to see these things close up. Looking forward to the last catch of the season this coming Saturday!

1 comment:

  1. I am often overdressed when birding in mid-Summer perhaps it too is a sign of senility!

    Laurie -

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