My brother (the white hot one) who now lives in Australia had this to say about the Sea Eagle.
'Nice pics. Seems like the bird is a first immature( 2nd calendar year) - still retaining the breast band, dark subterminal band (unusually blackish undertail), dark stripe from behind the eye. They should attain this plumage at about 1 year of age. The post-juvenile moult of the primaries (occurs outward) starting apparently when about 1 year. Some individuals may start body moult well before moult of the remiges.
The individual still has the juvenile outer primaries and most of the secondaries (except the very inner ones) as they are very pointed at the tip.At a guess, the bird is between 1 and 2 years old. They may take 4-5 years to attain full adult colours.
Second immatures ( at the beginning of their 3rd calendar year of age) should have white tails with at most some brown speckling on the outer webs of t5. They should also have generally more blackish mottling on the basal half of the undertail than first immatures (the picture seem to show a bird with whitish basal undertail).
All information gleaned from our HANZAB; thanks for making me look it up. Saw one this morning on a wet wader count. No pics unfortunately.
Chris'
In addition you might find the section pages 50-53 in Ferguson-Lees& Christie on raptor moult really interesting and helpful to a degree.
eRic
