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[Eagles] Imperial Eagle, Greater Spotted Eagle & While Bellied Sea Eagle

A juvenile bird?

It seems that the White-bellied sea-eagle photos shown here quite in agreement with the description
found in the book 'Raptors of the World' by J Ferguson-Lees & David A. Christie that the bird
is an juvenile. Here I have some questions hoping somebody reading my message would kindly answer.

a) Now the bird is well in March, so is it still proper to call it a juvenile, or a 1st winter bird,
   or a bird in its second year?
b) It can be seen that the inner primaries are growing out. Does it mean that the bird is undergoing
   a complete moult which is usual during 1st winter/spring time, or just partial flight feather moult?

Hope my wording proves not confusing.

Thanks for any illuminating comments?

S L Tai

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Dear eRic

Thanks for your answer. While satified with my basic enquiry, it also pushes me forward to further
enquiry which I will do so myself. While I was reading up 'Raptors of the World', I also noticed that Australia gets this bird around its whole coastal area.

By the way, I can't solve this little riddle H(handbook?)of A(Australia?) and NZ (New Zealand?)A(?)
B(book?)completely. Can you help with this too?

S L Tai

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Dear Gary

I personally think the term 'juvenile' is both safe and vague for a bird which has left its nest and is able to do independent feeding/hunting. 'Calender year' is, though coined in terms of human culture, gives us a good idea of the length of time after a bird is born. So if your knowledge that the young WBSE is over 14 months since born (presumbably you've been monitoring this individual since it has fledged somewhere in HK) is perfectly recorded, eRic's brother, who is in Australia, proves to have given us, particularly me, a sound judgement based on moulting pattern of WBSE in general.

I'm well convinced that the WBSE in question is in its 2nd calendar year.

Thank you here for eRic's answer for my 'riddle' and further information, for Gary and Beetle's
help with what can be found in the Society's bulletin.

S L Tai

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