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RE: What bird is this?

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Subject: RE: What bird is this?
From:
Date: Tue, 16 Mar 2004 09:44:16 +1100

I'd like to explore why people have suggested an "immature" drongo.  

The bird is clearly moulting it's tail feathers. You can see that the inside feathers are longer than the outside feathers - the typical manner in which tail feathers are moulted.  If the bird was immature (I suspect people are probably referring to juvenile rather than immature) then all the tail feathers would be growing at the same rate.  

Put another way, the fact that the feathers are staggered indicates that this bird is going through a moult rather than growing it's first set of feathers.  

There may be other reasons why an immature Drongo has been suggested (plumage, eye colour etc) but I didn't study the photo long enough to determine these (and I doubt these characters were able to be seen because of the light).  Many (most ?) passerines retain their juvenal tail feathers until the year after their birth so the pattern of moult seen in Bob's Drongo suggests that it is probably at least a year of age.

Cheers

David Geering
Regent Honeyeater Recovery Coordinator
Department of Environment & Conservation
P.O. Box 2111
Dubbo  NSW  2830
Ph: 02 6883 5335 or Freecall 1800 621 056
Fax: 02 6884 9382



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