Hello all again,
Just for completeness sake, wouldn't it be prudent to ensure that this bird
isn't a Kelp Gull? Whatever it is it is certainly on the male bulky side of
intermedius and fuscus if it is one.
I have posted a link to the images of the birds on birdforum.net which several
larophiles visit frequently. This is the tread:
http://www.birdforum.net/showthread.php?p=2644996#post2644996
All the best,
D.
> From:
> To: ;
> Date: Wed, 23 Jan 2013 01:19:57 +1100
> CC: ; ; ;
> ; ;
>
> Subject: Re: [Birding-Aus] Lesser Black-backed Gull at Broome tip
>
> Visa states " All in all, this individual seems to have so many "minor
> faults" that I would like to familiarize myself with the arguments that
> state this cannot be a dominicanus."
>
>
> I would suggest the bill is way too narrow for a kelp Gull, also the white
> trailing edge is equally too narrow especially at the inner primaries, and
> the degree of primaries extending beyond the tail tip compared to length of
> tail beyond tertials is too long allowing for this bird having lost its
> longest tertial. Olsen describes ssp melisandrae of Kelp Gull from
> Madagascar as having a smaller and slimmer bill than Cape Gull, but this
> Broome bird's bill would represent an extremely slimmer Kelp Gull indeed.
> However I admit to not having ever seen an image of melisandrae, can't find
> one anywhere.
>
> Cheers Jeff.
>
>
>
>
>
>
> -----Original Message-----
> From:
> On Behalf Of Harry Nyström
> Sent: Wednesday, 23 January 2013 12:29 AM
> To: Nikolas Haass
> Cc: Jim Allen; Danny Rogers; ; George Swann of
> Kimberley Birdwatching; Tony Palliser; Rohan Clarke
> Subject: Re: [Birding-Aus] Lesser Black-backed Gull at Broome tip
>
> Hello,
>
> Here are the first comments from Finland after my rough translation. The
> comments are provided by Mr. Visa Rauste, who has studied gulls for several
> years (decades?) and has been on the national rarities committee for almost
> 20 years of which 11 as the chairman (until 2011, when he left the seat).
> Another person is also quoted, and the person is clearly stated. I will
> still try to forward the photos to some other laridists for further review,
> but to my knowledge the comments by Mr. Rauste are practically as competent
> as can be.
>
> I'll keep you posted if other comments emerge.
>
> Visa's comments:
>
> *"First of all, the identification is very dependent on the accuracy of the
> white balance and correctness of the exposure of the images. If we go with
> the assumption that they are correct, the bird is definitely not a "normal
> heuglini". The upperparts of a heuglini should never be that dark and they
> should show a clearer bluish tinge. On the other hand, it should be noted
> that the line between a heuglini and a fuscus is not as clear as sometimes
> is suggested. And because of that, there has not been much support in Europe
> and especially in Finland to draw a line between these two taxons to split
> them into two different species.
>
> *
> *When it comes to the structure of the bird, it is to my opinion fuscus
> enough, but the structural difference between a fuscus and a heuglini is so
> small and more or less on the average that I wouldn't give it much weight
> when identifying an individual as a distant rarity on the other side of the
> globe.
>
> *
> *The moult is also better in line with fuscus, although I don't have my own
> data collected of wintering birds. The interruption of the moult in the
> primaries at this time of the year in that way is not typical for either
> taxons but is the "personal solution" of the individual that is probably
> related to the otherwise extraordinary life phases of the bird.
>
> *
> *A little disturbing feature comes to my mind regarding the photos: the iris
> of the bird is untypically dark for a fuscus, which almost always
> (especially during Summer) has a clear light yeallow iris. The iris should
> not show any or only slight spotting, when this individual shows it quite a
> lot: http://www.pbase.com/wildlifeimages/image/148413423
> *
> *
> *
> *I also have to say that I don't know anything about the gulls of the
> southern hemisphere, but I have to rely that the locals can identify and
> exclude them."*
>
> ------
>
> Visa's comments after having a good night's sleep in between when asked
> about the possibility of an intermedius:
>
> *"Yesterday I wasn't keen on trying to open the whole Lesser Black-backed
> Gull -dilemma, and I'm still not. But I'll open it just a little, anyway.
> The difference between an intermedius and a fuscus is a "line drawn in
> water" when examined on an individual level, although they are different
> enough as populations to deserve their subspecies status.
>
> In other words, a "dark intermedius" is identical to a "light fuscus". And I
> literally mean "IS identical", not "looks identical". ;-)
>
> *
> *Of course, an individual that is lighter than a typical fuscus and darker
> than a graellsii (or heuglini) can be called an intermedius. Note that such
> a bird might still be from the phasing region of fuscus and heuglini and not
> from the phasing region of fuscus and graellsii, which would be the
> "genuine" intermedius. Of course, even in Finland we have all kinds of
> LBBGs, for example like this - what would you call this:
> http://www.helsinki.fi/~rauste/gulls/hannu34.html
>
> *
> *Having said that, I still got the feeling yesterday that the individual is
> more "dark as a fuscus" than "dark as a typical intermedius". This concerns
> of course only the impression on the darkness (which is affected by many
> things, starting from the display one uses when viewing the photos). The
> darkness cannot be estimated accurately enough from photos, not even as good
> as these. If the bird was captured, one could use the Kodak-scale to assess
> the darkness of it; a typical graellsii is about 9-11, intermedius
> 11-13 and fuscus 13-17.
>
> *
> *But now all I can give is a "no can do", in addition to throwing out some
> impressions. Nevertheless: I have no reason to think this individual is a
> heuglini. No reason at all.
>
> *
> *But... Something still doesn't add up.
>
> *
> *The bird e.g. looks a bit long-legged, but it may not be essential.
>
> *
> *What could be essential is the pattern of the innermost primaries: if I am
> calculating the primaries correctly (differentiating the outermost secondary
> and the innermost primary is not as straightforward as one would think),
> this bird has black patterns only in the 6 outermost primaries (P4 might
> have a very small dot on the edge of the outer web, but can be seen only in
> some very close photos).
>
> *
> *Finnish birders, Antero Lindholm and Annika Forsten, have studied the wing
> tip patterns on Baltic Gulls (LBBG fuscus) of a known age, and in a data
> consisting of 138 +3cy individuals only 1 (one) bird had black in just the
> 6 outermost primaries: http://www.caluta.liitin.net/Caluta/Caluta1_l.pdf
>
> *
> *All in all, this individual seems to have so many "minor faults" that I
> would like to familiarize myself with the arguments that state this cannot
> be a dominicanus. Unfortunately I won't have the time to do this in the next
> few days."*
>
> -------
>
> Some other comments have also been given, this one from Petri Lampila, also
> a member of the national rarities committee:
> *
> *
> *"In addition to the minor faults already stated, the individual seems to
> lack all winter plumage features (streaking on the head). One would expect
> such winter plumage features from a northern hemisphere gull. I don't have
> experience from the fuscus in winter plumage, but for example the heuglinis,
> which I just recently saw in Goa (ca. 50 individuals), were all very clearly
> in their winter plumage. Of course there are exceptions to the rule, but the
> list of untypical features is starting to be a little long for a
> vagrant."*
>
> Additionally, the possibility of a hybrid should be taken into consideration
> somehow - at least according to some.
>
> Cheers,
> -Harry
>
>
>
>
>
>
>
>
>
>
> 2013/1/22 Nikolas Haass <>
>
> > 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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