Ok everyone, time to put the kettle on for a cup of tea and calm down.
Nobody should be embarrassed by how this bird is eventually identified because
it is a very difficult individual, so let's take stock of the awkward bits.
1- the bird has a somewhat hefty bill and that doesn't scream out fuscus.
2- it's a genuinely dark bird, this wasn't easy to work out from the earliest
photos, but Rohan's images clinch this, probably too dark even for typical nom
heuglini.
3- the wing is dark but black features on Ps5 and 6 are easily discerned
against greyer rest of feather, not really what you would expect on a fully
adult fuscus, but might not be impossible.
4- Rohan's dorsal shot shows the remnants of a small white mirror on inside web
of P9, apparently 5% to 16%(KM Olsen) of fuscus can have this especially males,
this sort of works with the bill size. White mirror on P9 is more common for
ssp intermedius which I have to say this bird looks a hell of a lot like
according to all of these awkward features and ignoring the extremely reduced
likelihood of that form ever reaching Australia.
5- this bird has dark tips to under-primary coverts and a mid-tone eye, both
features of immaturity in conflict with everything else shown by this bird.
Could the less than black inner webs of Ps 5 and 6 contrasting with black outer
feature consequently also indicate a younger adult fuscus, just throwing ideas
up in the air here. Would seem odd for a younger adult to show mirror on P9 but
that may be irrelevant. Fuscus is known to mature a year ahead of the other
Lesser Black Backed forms.
6- The bill is very bright yellow, this probably works better for fuscus than
heuglini.
So we are sort of left with an "intermedius-like" younger adult? fuscus. This
bird is definitely not easy and will probably be solved in Europe rather than
Australia.
Cheers Jeff.
-----Original Message-----
From:
On Behalf Of Nikolas Haass
Sent: Tuesday, 22 January 2013 10:27 PM
To: Mike Carter; Tony Palliser;
Cc: 'George Swann of Kimberley Birdwatching'; 'Jim Allen'; 'Danny Rogers';
'Tony Palliser'; 'Rohan Clarke'
Subject: Re: [Birding-Aus] Lesser Black-backed Gull at Broome tip
Hi Mike,
No, this is not an incredible way to argue because it wasn't intended to be an
experiment using the Broome gull as a 'control'. I was just wondering if the NW
India birds, in turn, can be used as a valid 'control' for the Broome bird.
There has been a long discussion about these birds in India and apparently it
still has not been resolved which taxa winter in NW India. So, yes, the Indian
birds could be heuglini OR taimyrensis.
To the Broome bird: It still doesn't look like a perfect L. f. fuscus to me for
the reasons I discussed in previous mails. I know that some people favour L. f.
fuscus, but to my knowledge a number of people besides me have made the case
for L. f./h. heuglini, too. I agree that the bird is too dark for taimyrensis,
which I suggested based on iris colour and bill shape. I am interested in the
identification of this bird and contributed to it to my best knowledge.
BTW in case the bird will be proven to be a L. f. fuscus, I won't be
embarrassed at all.
Nikolas
----------------
Nikolas Haass
Sydney, NSW
________________________________
From: Mike Carter <>
To: Nikolas Haass <>; Tony Palliser <>;
Cc: 'George Swann of Kimberley Birdwatching'
<>; 'Rohan Clarke'
<>; 'Danny Rogers' <>; 'Tony
Palliser' <>; 'Jim Allen' <>
Sent: Tuesday, January 22, 2013 9:59 PM
Subject: Re: [Birding-Aus] Lesser Black-backed Gull at Broome tip
Nikolas, what an incredible way to argue? It seems that you are saying that
because you say that the Broome bird is heuglini that is what it is and any
evidence leading to a contrary conclusion must be false. Surely the logical
conclusion is that the Indian birds are paler than the Broome bird because they
are heuglini as would be expected at that site whereas the Broome bird is
fuscus as the colour and other factors suggest.
Mike Carter
30 Canadian Bay Road
Mount Eliza VIC
3930
Tel (03) 9787 7136
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