Hi Mick,
Your description of the spurs was very thorough and, no doubt, the spurs do
play a role in the ID of Frigates. However, they can be very confusing, too.
What I was trying to say is that this field mark is quite often used too
superficially by some observers (obviously not by you, Mick!) to draw a
conclusion of the ID. Of importance, as discussed by you, is to age the bird
prior to attempting a species ID.
Cheers,
Nikolas
----------------
Nikolas Haass
Sydney, NSW
________________________________
From: Mick Roderick <>
To: Nikolas Haass <>; Mike Carter <>;
Steve Clark <>; ""
<>
Cc: 'David James' <>
Sent: Wednesday, January 16, 2013 10:06 AM
Subject: Tanzanians need help with Frigatebird id
Nikolas,
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?).
Mick
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.
Cheers,
Nikolas
----------------
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?? ;-)
Mick
________________________________
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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