Vega Gull photos from Japan

[Brian S]

Chris Gibbins is just back from Japan and has finished posting a reasonable sample of some great flight photos for reference. Also there are hints on how to separate from Mongolian.

http://chrisgibbins-gullsbirds.blogspot.com/

Brian S

[Brian S]

Here's a link to Chris's Vega Gull article on Surfbirds.

http://surfbirds.com/ID%20Articles/JapanGulls/index.html

Brian S

[JanJ]

Yes, as usual a fine set of images from Chris! Interesting wintip pattern in some of the vegae! Also further down some nice images of a classic first cycle mongolicus.

JanJ

[adriaens]

I have become a big fan of Mr. Gibbins!
Just a tiny detail (I love to nitpick...):
this supposed "2cy Vega" (http://1.bp.blogspot.com/_JXeDixaPw40/Sznp3BiJrZI/AAAAAAAABEg/6Q-JjSQU-uk/s1600-h/webIMG_1684.jpg) should be a 3cy (3rd cycle).

[JanJ]

Some more stuff from Gambell regarding vegae here:

http://larusology.blogspot.com/

JanJ

[Brian S]

I have become a big fan of Mr. Gibbins!
Just a tiny detail (I love to nitpick...):
this supposed "2cy Vega" (http://1.bp.blogspot.com/_JXeDixaPw40/Sznp3BiJrZI/AAAAAAAABEg/6Q-JjSQU-uk/s1600-h/webIMG_1684.jpg) should be a 3cy (3rd cycle).

Hi Peter

Chris has labelled this as '2cy' (2nd calendar-year or 2nd winter in old money) which as you say in December is 2nd cycle, but you age it as 3rd cycle (3rd winter). But what makes you age it as that?

In Howell and Dunn, image 25C.9 (p.177) there is a very similar image of a 2nd cycle with a 3rd cycle below (25C.11). The 3rd cycle seems very different, having a much more advanced plumage than Chris's, with almost wholly grey mantle and coverts, white tips on primaries, yellow bill. Based on H&D I would have aged this as 2nd cycle.

Brian S

[JanJ]

My initial impression of the vegae in question was a 2nd winter/2cy/2nd cycle type.
However, there´s considerable variation - as in argentatus/argenteus - to mention just these, some are more advanced than others and you will find some vegae labeled 3cy which lack white tips to primaries and have no visible mirror on p10 but with a full set of 3cy type plumage - adult like on scapulars and covert region, and little dark markings on the tertials and so on. If I know Peter the way I think I do, he has something up his sleeve. :wink:

JanJ

[adriaens]

I suspect it is a retarded 3rd-cycle bird. The trailing edge to the secondaries, e.g., looks very broad and white for 2nd-cycle. I have indicated a few things on a smaller version of the photograph; I hope it is allowed to post this here:

http://img442.imageshack.us/img442/942/vegagull3cjapandec09.jpg
Photo: Chris Gibbins (http://chrisgibbins-gullsbirds.blogspot.com/)

[Brian S]

Peter

What do you think of the '2nd-winters' from Japan listed here? http://larus.hp.infoseek.co.jp/vega.html

Brian S

[JanJ]

I wish I had payed more attention to those greater coverts, because the secondaries sticks out just underneath, and as Peter say´s well broad for a 2cy. It might also be correct that the size of the white primary tips are to prominent for a 2cy, although I wouldn´t put all my money on that one.

http://starling.dyndns.org/~birdkitahiro/hokkaido/gulls/gullindex/vegae/index.htm

http://starling.dyndns.org/~birdkitahiro/05gurep/top.htm

JanJ

[JanJ]

Some more examples of 2cy vegae or presumed 2cy mentioned by Chris:

http://chrisgibbins-gullsbirds.blogspot.com/2010/01/some-examples-of-presumed-second-winter.html

JanJ

[geo399]

Hi Peter et al

First, it is great that people are looking close enough at the pictures on by web site to recognize possible errors and misinterpretations - this leads to interesting discussions and debate for us all. Peter’s query made me question my rather instinctive ageing of this bird as a second winter (second cycle) and sent me off looking at other images from the trip; and of course Peter knows his stuff so I went off thinking that I must have made a mistake somehow. But actually, having looked at lots of other pictures, I still think it is a second winter.

Before accepting the more complicated explanation for its appearance (i.e., that it is a retarded third winter, as suggested by Peter), I think we should ask why the simpler solution (that it is a rather typical second winter Vega) is not the best one. Peter’s query focuses on the primary tips and the white trailing edge to the secondaries (the ‘skirt’), so I will try to discuss each of these features in turn.

I have now loaded up a number of images of perched Vega that I take to be in their second winter (http://chrisgibbins-gullsbirds.blogspot.com). I would say that the predominant pattern is for these birds to have a primary pattern which is extremely similar to the bird in question – a very narrow (barely discernable) pale fringe, with the fringe broadening and becoming paler to form a small but distinct white tip to each feather. So, while such clear pale tips may be rather unusual on the second generation primaries of Herring Gull, for example, I think they are rather typical (easily within the normal range of variability) for Vega.

For comparison, and just out of interest, I looked this morning at some images of American Herring Gulls published in well respected papers and aged as second winter (Lonergan and Mullarney, DB 26, No1, 2004). In fact Plates 42, 44, 45, 46, 47 and 48 of this paper show second winter smithsonianus with distinct white primary tips equal in size and distinctiveness to the Choshi Vega in question. So, this suggests that such tips are really not so unusual on second generation primaries.

I would also add that the primaries on all of these birds are distinctly brown, rather than the black or blackish of third generation ones. And, as pointed by Brian Small on his post on this thread, we would typically expect third generation primaries to have much larger white tips than the bird in question, and most likely also a P10 mirror. So again this leads me to believe that the primaries are second generation, and that it is a second winter.

Peter’s second point relates to the secondary skirt. The skirt on my bird does indeed look white and, on initial inspection, rather deep. As Peter indicates, this appears to be more in keeping with what we would expect of third generation feathers, and hence a third winter bird. But we cannot see the whole feather length, so are left interpreting what the pattern might look like on the open wing. I managed to find some other images of the same bird (actually with different light conditions) with its wing open (see the second and third images of the new post on the blog). What these images show is a soft diffuse pattern, with darker blotches on some feathers, rather than a deep, white and clear 'trailing edge'. So I think the problem of the apparent broad white trailing edge may simply be related to the fact that the feathers are not fully visible in the pose captured by my first photograph of this bird.

I looked at a few of my other Vega images and found a great variety of secondary patterns (see the last four images on the new blog post). If you look at these you will see that some birds certainly have narrow buffy brown fringes extending around the tip of each feather, forming a thin and somewhat diffuse trailing edge, quite unlike the bird in question and more like that which we expect of a second winter/cycle bird. Most interestingly, one bird actually has two and perhaps even three ‘types’ of feathers in its secondaries (see final bird). This opens up the possibility that they may be different generations, and hence that some second winter Vega may have (at least some) third generation secondaries. This is speculation, but the images do show a great variety of feather patterns and types in the secondaries of apparent second winter birds.

Well, I notice that this comment is getting rather long so I will stop. I hope I’ve helped rather than complicated the discussion, and that I have been able to explain how I have interpreted this bird.

I’m very happy to be proved wrong , but I suspect that it is a second winter (cycle), and that Vega and some other taxa show clear white tips to the primaries and a range of secondary patterns at this age. Again, glad that you are questioning these birds Peter.

[adriaens]

Great to see flight shots of the 'problematic' bird. I realise that the primary tips were indeed not a very good feature to use; I just thought I could add them up to the broad secondary tips.

The inner primaries, with their slight brown tinge, should safely age birds like this as 2nd cycle indeed.
I am puzzled by the pattern and colour of the secondaries though. The secondaries of the bird in question (http://2.bp.blogspot.com/_JXeDixaPw40/S1X5qgbEkVI/AAAAAAAABSQ/iOjVVx50TZc/s1600-h/web17.JPG) are not bluish grey, so I can agree that they are 2nd-generation feathers indeed, just with a pattern that I have yet to see in European Herring Gulls of the same age! However, a bird like this one (http://3.bp.blogspot.com/_JXeDixaPw40/S1X4rBA7G5I/AAAAAAAABQo/Qa4o_3vVykU/s1600-h/web1.JPG) definitely shows different generations of secondaries, and this seems to be the case in both wings. It looks like a 2nd-cycle bird (because of its brown inner primaries) that has replaced a number of secondaries already. It would be interesting to know if this happens more often in Vega Gull.

So... I thought it was possible to apply Herring Gull criteria for ageing to Vega Gull as well, but this may be a mistake.

Just to show that I was not on mushrooms or anything when questioning the age of that particular Vega Gull, there are some examples of very immature looking, 3rd-cycle European Herring Gulls, on this web page (http://picasaweb.google.be/Zorkyyy/3rdCycleHerringGull), e.g. birds n° 11, 14, and 23. Note the blue-grey inner primaries with prominent white tips. It can be nearly impossible to age such birds correctly if they are not seen in flight; this is even more true in (northern) smithsonianus.

[geo399]

Hi.

Thanks for your reply Peter. I think you have brought this discussion to what is potentially the most interesting point - that some Vega, by the time they have reached the very end of their second cal year, may have some third generation secondaries. Have they 'squeezed in' an extra secondary moult (relative to Herring) somewhere along the line? I'm a little reluctant to start inferring anything about the moult without observing/following the process itself through time, but the feather patterns we see on some late December birds do suggest that they may be doing/have done something interesting.

You are right in that it would be interesting to know how common this is. I was hoping to present some data on Vega at the Crete IGM this December but I'm not sure that I will have enough material to say anything useful/quantitative about this.

Chris