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WIlliam Maroldo
09-12-2008, 07:27 PM
What type of gull is this? (I think I know) Before you jump to conclusions, note the legs are yellow(this can be seen more clearly in other images I have of the bird). It is also a very large gull. Taken September 7, 2008, Quintana, Texas, Gulf of Mexico beach. regards~Bill

John Chardine
09-12-2008, 08:33 PM
Nice one William. I think I know but I'll wait for other "guesses"!

John Hawkins
09-13-2008, 08:36 AM
I think it is a Kelp Gull.
John Hawkins

Dave Hassell
09-13-2008, 01:56 PM
It could be a Lesser Black-backed Gull.

WIlliam Maroldo
09-13-2008, 08:47 PM
John: you are half right! There are islands off the coast of Louisianna..... regards-Bill

John Hawkins
09-13-2008, 10:54 PM
My other guess was a Herring Gull. Is it both?

John Hawkins
09-13-2008, 11:09 PM
You peeked my curiosity so I googled louisiana gulls and found Chandeleur Gulls! Very interesting hybryd. This is why this is a great site, we learn something all the time. Thanks,
John

WIlliam Maroldo
09-14-2008, 07:32 PM
John: good job. You guessed both herring and kelp gulls.And then you figured it out. There is a good article on Chandeleur gulls here:
http://www.aba.org/birding/v37n3p266.pdf (http://www.aba.org/birding/v37n3p266.pdf) regards~Bill

John Chardine
09-14-2008, 09:22 PM
I guessed a Kelp Gull/Dominican Gull/Southern Black-backed Gull but kept it to myself! I've seen 1000s in Antarctica over the years. Interesting article although I don't see anything in this image which suggests a hybrid with a Herring Gull. What am I missing?

WIlliam Maroldo
09-14-2008, 10:53 PM
In the first place I am no expert, and it is possible the ID is incorrect.(I said "I think I know") I have based the ID on several sources, and the article I had a link to here wasn't one of them.(I just found it) At first glance, I thought it was a herring gull, which are fairly common here as juveniles, but not adults. However, Herring gulls normally have pink legs, and these are yellow. I have never seen a Kelp Gull. This bird was very large, larger than the few herring gulls I've seen at least(and at least 1/3 larger than any other gull common on the Tx coast. It is was too large to be a LBBG. There was a positive ID of a Chandeleur gull in 1998 at the location this photo was taken.(there was considerable disagreement before positive ID was made)
Gulls of the Americas states:
Interbreeding of these two species has been reported from Louisiana since the 1990s..., and hybrids probably range throughout the Gulf of Mexico and perhaps the Caribbean.
The presumed F1 hybrid adults resemble Lesser Black-backed Gull (graellsii subspecies) or Yellow-footed Gull in their slaty gray upperparts... they tend to be similar in size and structure to Kelp Gulls, with swollen-tipped bills, yellow to greenish yellow legs, and orange orbital rings.
Several other factors convinced me at least, for what that is worth.

The possibility exists that the ID that I and several other people came up with was incorrect. If so, what is the gull? regards~Bill

John Chardine
09-15-2008, 05:54 AM
Bill et al- I buy the idea of a Kelp Gull, just not necessarily a hybrid. Lessers are much lighter that this one on the mantle and they are about the same size as a Herring. This one is definitely dark enough to be a Kelp, and I think too dark for Yellow-footed either, based on Sibley (never seen one myself). This bird also has the facial "jizz" of black-backed gull such as Kelp- notice the large distance between the eye and the bill.

I'll dig through my Antarctic images and find a Kelp Gull from there.

WIlliam Maroldo
09-15-2008, 05:34 PM
I was looking at a number of images of Kelp gulls on the internet. What struck me was that there were a lot of really bad photographs there, bad angles, chromic aberration all over the place, blurred and not sharp images, etc. It really made me appreciate the images presented here at BPN, and my little old gull picture holds up pretty well. In any case the Kelp gulls I looked at had somewhat smaller bills, smaller red bulge at the bill tip, less of an "overbite", but most noticeable was the distance from the eye to the bill was considerably less than in my image. Other than that there were many similarities. The fact that the Kelp gull is a Southern hemisphere bird is perplexing as well. regards~Bill

John Chardine
09-15-2008, 08:15 PM
Here's a pair of Kelp Gulls at Ushuaia, Nov 2005 (male probably on left). These show clearly the prominent gonys (pointy bit in bottom mandible). Bill- yours is less prominent. Kelp Gulls are very dark backed but this is notoriously difficult to judge in a image because exposure and lighting affect the shade. Kelp Gulls are seen regularly along the Gulf coast and as the article referenced by Bill indicates, the species has bred in the US.

I'll post a Lesser Black-backed Gull for comparison next.

John Chardine
09-15-2008, 08:16 PM
Lesser Black-backed Gull at Isle of May, Scotland, August, 2008. Note the relatively "dainty" look of the head compared to the previous images.

WIlliam Maroldo
09-15-2008, 09:34 PM
John: very interesting. To me, at least, my gull isn't either. About the lighting, my gull image was taken under less than ideal lighting conditions, and it is conceivable that the dark back of the gull is even lighter than it appears in the photo. I would bet on it. I think we can rule out a Kelp Gull, even though, as you stated, are seen regularly on the Gulf Coast. It is my understanding that LBBG are quite a bit smaller as well, and we safely rule that out. So where does that leave us?
Now that I have your attention, I have a question about birds and hurricanes. Did you notice I live in Houston? Anyway, it seems that many small birds that sought the shelter of trees were killed either by the wind or the uprooting and destruction of the trees. The question is about the other birds, the egrets, herons, and other birds that might have escaped or found other methods of survival. As I was unsuccessfully looking for ice today I did see several great and snowy egrets that seemed non-the -worse for wear. The question is how do hurricanes effect the bird populations? regards~Bill

Wayne Richardson
09-16-2008, 11:35 AM
I must say that on 1<SUP>st</SUP> viewing, I though Lesser Black-backed (LBBG) & probably a graellsi male. This was based on an obvious contrast between mantle & primaries. That said, I wasn’t totally convinced as there were some features that didn’t look right, e.g. rather heavy bill & brownish tone to the mantle; even allowing for the obvious colour cast on image.

Having researched further, read the ABA article & comments/posts by others it is clear to me we are really looking at just 3 options, i.e. LBBG, Kelp (KG) or a ‘Chandeleur’ gull (CG) which is a hybrid of American Herring Gull (AHG) & KG.
<O:p></O:p>
Details derived from ‘Gulls of Europe, Asia & North America – Olsen & Larsson’ reveal that Kelp (54-65 cm) & American Herring (53-65 cm) have almost exactly the same size range. Note LBBG (49-57 cm) overlaps with both species &, as with most gulls, these will be the larger males.

In addition, the authors used the Kodak Grey Scale to determine mantle colour. KG scores 13.5-15 which is indicative of it being one the darkest mantled gulls in the world. However, LBBG covers a much wider spectrum across its 3 subspecies, i.e. 8-17! Most graellsi fall within 8-11 range, with fuscus being the darkest race. Intermedius, as its name suggests is in between & are in the range 11-13. Note the black primaries on most species are 17-18. Although not easy to measure from an image, William’s bird appears to be in the 11-12 range, which would appear to eliminate KG.
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Another non-KG feature of the Quintana gull is the relatively large eye size. Note both KG in John’s post have rather ‘piggy’ eyes. So I would rule out that species on this aspect, plus mantle colour & bill size.
<O:p></O:p>
Moving on to the LBBG option, John’s LBBG post is almost certainly a (small) female, given its 'softer features' & round-headed appearance. I’ve now posted a male, ironically also from the Isle of May, which is much closer in appearance to the mystery gull.
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I understand LBBG is a very scarce winter visitor to the gulf during November to April. So you have to ask is a summer plumage adult LBBG more likely to be found in Texas in September than a dispersing ‘graellsi-like’ KG/AHG F1 hybrid from a known population in the next state?
<O:p></O:p>
If there are other images that show leg length & colour, then I would ask that be posted on this thread. I would be reluctant to commit to an ID assessment on a single contentious image when others are available, especially when they may eliminate one of the contenders.

WIlliam Maroldo
09-16-2008, 01:09 PM
As per Wayne's request I have included an image with 4 views of the mystery gull. Leg length is pretty well illustrated. Unfortunately my attempts to get closer, at the time, resulted in the gull flying straight out to the gulf.
regards~Bill

John Chardine
09-16-2008, 03:20 PM
Excellent comments Wayne! Yes, sex is a big factor in how a gull looks. Bill's new images are VERY useful and I think exposure and lighting aside, we have a fairly light-mantled dark-backed gull of some sort. Lesser Black-backed has been discussed and am leaning that way. However, while we are on the subject what about Yellow-footed- L. livens (never seen one)? Sibley gives the yellow-footed as "bulky" with a bright yellow eye ring. I think Bill's original image shows a reddish eye ring. Yellow-footed range is closer to Texas than that of the LBBG but is there anything else that eliminates L. livens?

Arthur Morris
09-22-2008, 07:24 AM
Just to stir the mix a bit: has anyone considered the white primary windows? They are perfect for Lesser Black-backed Gull and way off for Kelp Gull...

John Chardine
09-22-2008, 09:57 AM
This may be a reliable feature in this case Artie. However, generally, the white in wingtips of gulls is often quite variable geographically within a species so may be diagnostic in limited cases. I am away from my reference material right now but will try to look into this. LBBG certainly has come up as a possibility for this mystery gull.

Arthur Morris
09-22-2008, 10:15 AM
I understand that there can be racial and regional differences in the patterns of the white primary windows but in this case the differences are huge... Would love to here from Wayne on the windows issue.

Dave Brown
09-25-2008, 06:49 PM
Hi,

Thought I'd chime in here. I've spent the last 10 winters in Newfoundland observing gull daily, thousands a day adn there are often up to a dozen LBBG's present. Although, I have no experience with either Kelp or Yellow-footed Gulls. Having said that of the three species I guess I favor LBBG. The bill looks heavy for LBBG but I have seen several large males that have bills that are often the size of Herring Gulls. The birds mantle is certainly well within the range for Graellsi LBBG and I think too pale for Kelp Gull,considering they are supposed to have the darkest mantles of any gull species. I think is is difficult to comment on the mirrors without seeing the open wing- that would have made an ID much easier, although variable, primary pattern and the size and location of primary window are certianly an intergral identification tool. In this case the apical spots are very tiny, I see this a lot on adult LBBG's not sure how often you'd see this on Kelp or Yellow footed. As well the bird appears to have a fairly narrow tertial step, it actually looks perfect for LBBG but perhaps a bit narrow for Kelp- I don;t know anything about the width of Yellow footed tertial steps. Anyway guys, my opinion is that this is an adult Lesser Black-backed Gull.

Dave Brown

Wayne Richardson
11-21-2008, 12:26 PM
Hi All

I thought you might be interested in this Kelp Gull (http://www.surfbirds.com/cgi-bin/gallery/display.cgi?gallery=gallery10)photographed by Devlin Bosler this month & also from Quintana Beach. Note it will only be 2nd Texas record, if accepted & the 'dreaded' hybrid is eliminated! :D

However, it provides a very good comparison with William's Lesser Black-backed Gull e.g. note leg & mantle colour, plus quite different jizz.

Cheers: Wayne

PS: My belated answer to Art's query about primary 'windows'. :o It appears northern graellsii LLBG moult later than southerly breeders. Some actually don't acquire new P9/P10 until Feb or even early Mar. So a northern bird would have quite abraded (totally dark) primaries in Sep & this has already been reported for autumn (fall) birds in Texas. So features of William's gull actually matches previous LBBG seen in that state & it probably originated from Iceland.

WIlliam Maroldo
11-21-2008, 07:56 PM
The funny thing is that I first posted the gull image on Bird Forum (months ago) and my first guess (truely a shot in the dark) was a lesser black backed gull. I was led to believe it was a Chandelier Gull. and that my "guess" was incorrect. Here we go months latter, and it appears my first guess was correct. Go figure.