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        Discussion Area 討論區 >> Bird Identification 鳥類辨識 >>  Frigatebird sp
        
(Message started by: geoff_welch on May 5^th, 2006, 10:08pm)

Title: Frigatebird sp
Post by geoff_welch on May 5^th, 2006, 10:08pm

http://www.geocities.com/geoffwelch46/fr1http://www.geocities.com/geoffwelch46/fr3
Po Toi
3/5/2006

This frigatebird was around Po Toi for about 5 hours on Wednesday. I marked it as an immature Lesser because of the white spurs on the underwing and comparison of size with Black Kite. Is it?

Title: Re: Frigatebird sp
Post by miket on May 6^th, 2006, 11:49am

I think this is Lesser, apparently a fairly young one which has not yet lost its breastband and is thus juvenile or first stage immature (perhaps to be taken as the same thing), and certainly not yet second stage immature, to use the aging terminology employed by Robson in Birds of SE Asia.

Mike Turnbull

Title: Re: Frigatebird sp
Post by Mike Chalmers on May 20^th, 2006, 2:50pm

Dear Geoff,

Agree with Mike T that this is a first stage Lesser Frigatebird. The prominent white axillary spurs indicate it can only be either an immature Lesser or Christmas Island Frigatebird. The size comparison with Black Kite shows it be a Lesser, whereas Great and Christmas are significantly larger and heavier all round. Other pointers to Lesser are the shape of the white underparts with the spurs level with the rear of the breast band, the white on breast and belly forming a neat triangle with the point against the dark lower belly. The white on first stage Christamas usually appears larger and wider and extends lower down to vent.

For pics and comparison of all 3 frigatebirds in HK, see paper in 1998 HK Bird Report.

Mike Chalmers [= Mike C]