Before we even try to id this bird we must agree on its age. My personal view is that it is in first winter plumage (advanced). If you click on the images and blow them up you can clearly see markings on the mantle. You can clearly see the markings on the tertials without blowing them up. If it was a first summer bird then I would have expected the bird to be much cleaner showing much less traces of juvenile feathers as Martins previous picture shows.
The bottom picture shows the bird preening, is it me or can I see a dark edge to the two outer feathers (would that not suggest Arctic) I believe Roseate doesnt show this feature, (I may be wrong). Any more suggestions!
2 comments:
could be advanced (ie going against the usual moult time) or is it retarded, don't think we'll ever know
Terns of Europe and North America suggests very little difference between 1st winter and 1st summer because of the variation, I've only ever seen three - shall we say 1st years, one in Iceland in June was showing very faint markings on the mantle and tertials
See an article on the Birdwatch web site about common and arctic terns, it states that by the time juvs start to move south they have already lost most of their juvenile features and therefore would be in 1st winter plumage.
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