We (Rohan Clarke, Richard Baxter, Frank O’Connor and I) are back from Broome where the Lesser Black-backed Gull was easily found and viewed. Before we got there George & Jim had taken more photos from better angles, fuller profile shots, which confirmed our judgements from the earlier images. While we were there ca. 1,000 photos were taken notably by Rohan Clarke, photographer extraordinaire, and nine of those are already in circulation and will no doubt, soon be posted on his web site http://www.pbase.com/wildlifeimages but I did not find them when I looked this morning. Virtually all aspects are depicted. Firstly for those interested in twitching this bird, the rubbish tip is in the ominously named Buckley’s Street (or Road), a ten minute drive from China Town, Broome. Probably because we there on a Saturday morning when no heavy vehicles were operating, there was no hesitation from gate control in allowing us in. Note that we arrived at different times in 4WD vehicles and were allowed to drive anywhere but wandering about on foot was not permitted. Entry on week days and after rain may be more difficult and due to the undulating nature of the site, the bird is unlikely to be easily visible from outside the fence. The site was muddy with pools of water and torrential rain that afternoon after we had left may have made it impassable. The bird was present throughout our stay, often associating with Silver Gulls. As previously stated, anyone experiencing difficulty should contact George Swann. And don’t forget that the Semi-palmated Plover should still be around Broome. Whilst this bird could easily be mistaken for a Kelp Gull, there are several characters, some more subjective than others, that proclaim that this is not a Kelp Gull. These include structural features such as general shape being more gracile, smaller head, slighter bill as well as plumage features such as more greyish tones to upperparts. The most convincing, measurable features are the obviously longer wings projecting much further beyond the tail and the moult stage. The bird is one of two similar taxa, which according to the latest IOC classification as adopted by BARC, are both subspecies of Lesser Black-backed Gull Larus fuscus. These are the nominate fuscus (Baltic Gull) favoured by some, me included although I oscillate, and the race heuglini (AKA Heuglin’s Gull) favoured by others. Most consider it too dark for the race taimyrensis. Expressing the moult situation in the manner set out by Nikolas in the email below obscures important details. There are clearly two feather generations in the primaries. Whilst slightly worn indicating that they are not fresh feathers, p1 to p6 are much newer than p7 to p10, which are very old and worn. Whilst this moult pattern does fit heuglini, it also fits fuscus so is of little or no value in determining subspecies. Using the wing tip diagrams in the Olsen & Larsson Gull book pages 26-32, the darkness of the primaries is a better fit for fuscus, whilst the size of the remnant mirror on p10 is a better fit for heuglini. I also feel that the total lack of dark streaking on the head or neck that is supposedly a feature of winter plumage in both contending taxa favours fuscus as that race has the least amount of streaking.
Mike Carter 30 Canadian Bay Road Mount Eliza VIC 3930 Tel (03) 9787 7136
Klaus is in Thailand and won’t get home till February, cheers Jeff.
Sent: Tuesday, 22 January 2013 8:04 AM Richard Baxter; Jeff Davies
Hi Dimitris et al.,
To my knowledge intermedius, graellsii and heuglini are very similar to each other regarding upperpart coloration. As I said earlier: Whilst I agree that the upperpart coloration is too dark for taimyrensis, it also doesn’t look good for fuscus. A fresh fuscus is almost black with almost no contrast to the primary tips. A worn/bleached fuscus develops a brownish tinge to the upperparts. This is in contrast to the cold dark grey upperparts of the Broome bird.
The jizz fits best heuglini. To me the bird looks too heavy, too long-legged, too short-winged, too big-headed and too large-billed for fuscus.
I agree with Jeff Davies that the primaries (p1-6 versus p7-10) as well as the secondaries are of two generations (initially I thought that all primaries were old). This interrupted moult is according to Martin Gottschling and Axel Mueller typical of three taxa: fuscus, heuglini and taimyrensis (apparently not for graellsii and intermedius – I need to check the literature).
So, taken everything together I would still say: L. h. heuglini, 3rd or 4th winter.
What is Klaus Malling Olsen’s opinion on this bird?
Cheers,
Nikolas
Hi Dimitris et al.,
To my knowledge intermedius, graellsii and heuglini are very similar to each other regarding upperpart coloration. As I said earlier: Whilst I agree that the upperpart coloration is too dark for taimyrensis, it also doesn’t look good for fuscus. A fresh fuscus is almost black with almost no contrast to the primary tips. A worn/bleached fuscus develops a brownish tinge to the upperparts. This is in contrast to the cold dark grey upperparts of the Broome bird. The jizz fits best heuglini. To me the bird looks too heavy, too long-legged, too short-winged, too big-headed and too large-billed for fuscus. I agree with Jeff Davies that the primaries (p1-6 versus p7-10) as well as the secondaries are of two generations (initially I thought that all primaries were old). This interrupted moult is according to Martin Gottschling and Axel Mueller typical of three taxa: fuscus, heuglini and taimyrensis (apparently not for graellsii and intermedius – I need to check the literature).
So, taken everything together I would still say: L. h. heuglini, 3rd or 4th winter.
What is Klaus Malling Olsen’s opinion on this bird?
Cheers,
Nikolas
Brillian Pictures Rohan.
For me this bird is too dark to be Heuglins, with perhaps more fitting candidates being fuscus or intermedius…
And then of course you have all the wonderful north hemisphere gull hybrid combinations…
All the best,
D.
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Hi all,
Congratulations to these great shots, Rohan! Whilst I agree that this guy is too dark for a Larus (heuglini) taimyrensis, I still don’t like the idea of it being a Larus fuscus fuscus. I still think that the bird is too bulky and that its upperparts are too cold dark grey for a L. f. fuscus. My ID would still be Larus heuglini. Contra my initial comment, more likely L. h. heuglini than L. h. taimyrensis.
Cheers,
Nikolas
Hi,
As we have the nominate race of the Lesser Black-backed Gull (Larus fuscus fuscus) breeding here in Finland and several Heuglin’s Gulls (Larus fuscus heuglini) passing by each year, I would be happy to forward some images to some Finnish “laridists” for assessment if you want to. Just let me know when the photos are available and if you would like to hear another opinion, and I’ll handle the rest.
Cheers, -Harry
2013/1/21 Mike Carter
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