Tanzanians need help with Frigatebird id

To: Nikolas Haass <>, Mike Carter <>, Steve Clark <>, "" <>
Subject: Tanzanians need help with Frigatebird id
From: Mick Roderick <>
Date: Tue, 15 Jan 2013 15:06:25 -0800 (PST)
Would you mind expanding on the 'axillary spur business' as I'm now thoroughly 
confused and would have though that this ID could have ruled out Great on the 
basis of the spurs (hence my confusion). 
David comments that juvy Greats (when they actually have spurs) have "spurs 
that originate off the side of the belly patch and extend only onto the flanks, 
just like this bird." I am actually seeing the spurs originating from the front 
of the belly patch, and this combined with the prominence of the spurs and the 
possibility that they are also just reaching the underwing has me confused - 
maybe this is what you're referring to?
I'm very happy to concede the subject bird is not an Ascension (and I 
originally thought Lesser would be a better fit than Greater but I take on 
board David's comments there) - moreover I'm curious about your comment on the 
spurs (i.e. should we not be using them as a reliable character?).

From: Nikolas Haass <>
To: Mick Roderick <>; Mike Carter <>; 
Steve Clark <>; "" 
Cc: 'David James' <> 
Sent: Wednesday, 16 January 2013 9:19 AM
Subject: Tanzanians need help with Frigatebird id

Hi all,

I agree with Mike and David that the bird is most likely a Great Frigatebird. 
Re Mick's comment: I believe that the 'axillary spur business' has caused many 
Great Frigates on Michaelmas Cay to be misID'd as Lesser Frigates (yes, I know 
that there are Lesser Frigates, too).
Re David's comment on Magnificent Frigate on Cape Verde: Sadly, to my 
knowledge, there are only three to six birds left in that relict population.



Nikolas Haass

Sydney, NSW

From: Mick Roderick <>
To: Mike Carter <>; Steve Clark <>; 
"" <> 
Cc: 'David James' <> 
Sent: Tuesday, January 15, 2013 5:49 PM
Subject: Tanzanians need help with Frigatebird id
Mike, Steve et al,
I'm not sure if my other post reached the list (it hasn't hit my inbox), but 
wouldn't a sub-adult Great not have any axillary spurs at all? The ones that 
are on the subject bird are also set a long way forward on the belly patch and 
are quite prominent, which would rule out Great as well. They actually appear 
to reach the underwing in some of the images.
On plumage I think CI and Lesser the main potential confusion species, but as 
you say Mike the bill doesn't look long enough for CI. The belly patch looks 
the wrong shape for Lesser and it doesn't seem to "point backwards" on the 4th 
image, which shows the best view of the bird's underside...but as I said I 
think the spurs could actually reach the underwing of the bird.
I would be hesitant to use Pizzey as a guide for this (or other young frigates) 
and I also don't think we should identify on range either, rather what the bird 
actually is.
 Would it be impossible for a bird like that to round the Cape?? ;-)

From: Mike Carter <>
To: Steve Clark <>;  
Cc: 'David James' <> 
Sent: Tuesday, 15 January 2013 1:59 PM
Subject: Tanzanians need help with Frigatebird id
In case he missed this posting, I've forwarded this request to David James who 
knows this group well having lived for three years+ on Christmas Island where 
all three Australian
 species breed. David wrote a paper on their ID published in 2004 in 
BirdingASIA 1, 22-38.

However here are a few comments from me. It is a sub-adult bird but because it 
appears to have a wholly white head lacking any tawny colouration, it is not a 
fresh juvenile. The white spurs seem to me to be restricted to the sides of the 
breast not extending onto the underwing which suggests to me that it is not a 
Lesser Frigatebird. The bill doesn't look long enough for a Christmas 
Frigatebird so assuming that it is of Indian Ocean origin, (Ascension Island is 
in another ocean without a tropical waters link), my not very confident vote 
would be for Great Frigatebird.

Mike Carter
30 Canadian Bay Road
Mount Eliza  VIC 3930
Tel  (03) 9787 7136

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