Tuesday, May 30, 2006

I Hate Gulls: Mystery Gull Photo

OK, I must admit it: I HATE gulls.

But I know there are quite a few masochists out there that love gull identification, so this post is for you.

Name this gull:

OK, so it's not a super-tricky photo, but perhaps a bit trickier than it would appear to be at first glance. Can't say any more without giving it away.

The photo was taken by one of Chicago's best young birders, Jim Giacinto, and I'll tell the full story of this bird after (if) we get a few comments.


Bill Pulliam said...

Um, OK, maybe I'm just a philistine who wouldn't recognize a second-year Sabine's X Common Black-headed hybrid if it perched on my left forefinger... but I'm still looking for any reason why it is NOT just a Franklin's Gull with a slightly washed out (worn?) head?

Birding is NOT a crime!!!! said...

We're pretty sure it's not a Franklin's Gull.

Bill Pulliam said...

Well if we're dealing with hybrids or species not regularly occuring in North America, then I throw in the towel without being able to see size, tail, and wing pattern in flight. Other than a slightly pale-ish head and sort of dingy pale-ish feet (compared to typical Franklin's), I'm not picking up much...

Unless it was not taken in North America and you care to happen to mention what continent it WAS taken on...? Naw, you'd never be sneaky like that.

Bill Pulliam said...

Wait, wait... I just saw it, of course! How could I have been so blind?

It's a Pileated Woodpecker!

Mike's Soap Box said...

Well it's not a Franklin's Gull because the primaries do not show enough white mirrors on the folded primaries. On the photo there is one large white mirror on P10.

A Laughing Gull adult do not have any white mirrors on the primaries and the wing tips are blackish.

This is Bonaparte's Gull because Bonies do not have red bills and this gull is to large for a Bonaparte's.

This is not a Black-headed Gull because the hood should be more brown then gray and the mantle looks to be to dark.

It's not a Sabine's Gull because the bill is black with a yellow tip and of course this gull is to large for a Sabine's or a Little Gull.

So I am going back to Franklin's Gull x ? with something producing this hybrid. The mantle color fits a Franklin's, the bill color but the legs are lighter than it should be on a adult bird and the wing pattern doesn't fit a Franklin's.

I do know its a gull and I get points for that!

Mike's Soap Box said...

WELL I went to Ill. Listserv and it seems birders in Montrose are reporting a adult Laughing Gull! IF this blog is questioning the sighting and IF this young birder took this photo of this adult Laughing Gulln then we might be part of poll because it's possible that the blog owner has doubts on this gull.

I looked at the photo again and there is that white mirror on p10 that Laughing Gulls do not have. I went to many Laughing Gull sites and even checked several resources and Laughing Gulls do not have any mirrors on the primaries and not even underneath the primaries.

IFF I am way off base and the gull at Montrose is a Laughing Gull than great but if that photo is the same bird being reported at Montrose than the records comm. will have to figure this out to be a poss hybrid.

Either way the photo is not a Laughing Gull based on the wing patten.

Birding is NOT a crime!!!! said...

This is not a photo of the adult Laughing Gull that has been seen recently at Montrose, but the rest of Mike's comments are pretty much right on the mark. (See, those professional bird guides do know how to identify birds!)

I think the identity that has been assigned to this bird by our local birders is correct, but I'm not sure that identity can be "proven" by the photo. (This is the best photo we have, there are no flight photos of this bird.)

I will wait another day or so until I post the full back story about this bird, and the "story" about this bird also provides some key identfication clues.

Bill Pulliam said...

Isn't assigning hybrid parentage based just on plumage and soft-part colors a kind of iffy undertaking? I know it is done all the time with gulls, but it seems quite a leap of faith to me much of the time.

Having said that... I can see a Franklin's x Ring-billed or Franklin's x California coming out like this bird. This is where size would be helpful. It looks like it might have a relatively robust bill and overall build, which would lean me away from Franklin's x Mew. Plus Franklin's breeding ranges overlap extensively with Ring-billed and California, and only slightly with Mew (or Lesser Black-backed, for that matter). Since the mantle looks to be about as dark as a regular Franklin's, that might lean me more towards California... but again some idea of size and robustness would help there.

I'm assuming the bird must have some difference from typical Franklin's in size and shape, too? If not, I'd think you have to seriously consider that it could just be a pale-legged Franklin's and not a hybrid. I don't have as much faith as Mike does that the photo of the folded wing can tell you that it has fewer white windows than a Franklin's should; I can just say that it has at least one.

Go get a cheek swab for a DNA sample!

Anonymous said...

Confirmed IBWO. I hope you're not calling me a liar.

Birding is NOT a crime!!!! said...

Ummm, since this post is not about the IBWO, and you didn't leave your name, I have no idea who you are or what the hell you're talking about.

But hey, if the shoe fits...

Bill Pulliam said...

Ok so, spill... what does BINAC think the gull is?

Birding is NOT a crime!!!! said...

Yeah, I almost forgot about it, the bird is almost certainly a hybrid Laughing Gull/Ring-Billed Gull.

Just to double-check this id, I sent the photo to Martin Reid, who is a well-known gull afficianado who currently lives in Texas. (I took one of Martin's Rufous-capped Warbler tours a year or two ago and it was a lot of fun.) Martin nailed the id right away.

I'm not sure how common this hybrid is; I could not find a photo of a similar bird anywhere on the web, but my search was not exhaustive. A bit more about why this particular gull is a LAGU x RBGU when I have the time.

Anonymous said...

"It's a Pileated Woodpecker!"

Coincidentally, I saw a pileated in my backyard this past weekend. I have tons of hardwood trees on my property for them to enjoy. If you were making a joke, I assume you meant to say it was an ivory billed woody.