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ID-FRONTIERS for January 1-6, 2007
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Messages are displayed in the order they were received.
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| Subject | From | Date | Time |
| "Ipswich" Savannah Sparrow | gdentremont(AT)JUNO.COM | Mon, 1 Jan 2007 | 8:40pm |
| Re: Redpoll ID challenge | Jeff Bouton | Tue, 2 Jan 2007 | 7:58am |
| Re: "Ipswich" Savannah Sparrow | Ian A. McLaren | Tue, 2 Jan 2007 | 9:06am |
| FWD: Peregrine Falcon deduction / identification
using reactions of other birds | Nate Dias | Wed, 3 Jan 2007 | 2:57pm |
| seeking feedback on two more gulls | Martin Reid | Wed, 3 Jan 2007 | 8:16pm |
| Glaucous-winged Gull in Gloucester, UK | Dick Newell | Thu, 4 Jan 2007 | 6:48am |
| Re: Glaucous-winged Gull in Gloucester, UK | sgmlod(AT)AOL.COM | Thu, 4 Jan 2007 | 9:00am |
| Re: Glaucous-winged Gull in Gloucester, UK | Lethaby, Nick | Thu, 4 Jan 2007 | 9:11am |
| Re: Glaucous-winged Gull in Gloucester, UK | Alan Contreras | Thu, 4 Jan 2007 | 9:25am |
| Re: Glaucous-winged Gull in Gloucester, UK | Phil Pickering | Thu, 4 Jan 2007 | 10:37am |
| Re: Glaucous-winged Gull in Gloucester, UK | Alvaro Jaramillo | Thu, 4 Jan 2007 | 10:58am |
| Re: Glaucous-winged Gull in Gloucester, UK | Alvaro Jaramillo | Thu, 4 Jan 2007 | 11:03am |
| Re: Glaucous-winged Gull in Gloucester, UK | Phil Pickering | Thu, 4 Jan 2007 | 12:04pm |
| Japanese GWGUs | sgmlod(AT)AOL.COM | Thu, 4 Jan 2007 | 12:37pm |
| Re: Japanese GWGUs | Lethaby, Nick | Thu, 4 Jan 2007 | 12:43pm |
| Re: Glaucous-winged Gull in Gloucester, UK | Lee Evans | Thu, 4 Jan 2007 | 2:55pm |
| Re: Glaucous-winged Gull in Gloucester, UK | Alan Contreras | Thu, 4 Jan 2007 | 3:21pm |
| Glaucous-winged age | Alvaro Jaramillo | Fri, 5 Jan 2007 | 12:09am |
| Re: Glaucous-winged age | Dick Newell | Fri, 5 Jan 2007 | 2:34am |
| Re: Glaucous-winged age | Norman D.van Swelm | Fri, 5 Jan 2007 | 9:30am |
| Re: Glaucous-winged age | Lee Evans | Fri, 5 Jan 2007 | 10:44am |
| Re: Glaucous-winged age | Phil Pickering | Fri, 5 Jan 2007 | 11:04am |
| Re: Glaucous-winged age | Phil Pickering | Fri, 5 Jan 2007 | 11:15am |
| Re: Glaucous-winged age | Alvaro Jaramillo | Fri, 5 Jan 2007 | 11:41am |
| Re: Glaucous-winged age | Lee Evans | Fri, 5 Jan 2007 | 12:08pm |
| Re: Glaucous-winged age | Lee Evans | Fri, 5 Jan 2007 | 12:16pm |
| Re: Glaucous-winged age | Lethaby, Nick | Fri, 5 Jan 2007 | 12:28pm |
| Causes of extreme vagrancy | Wayne C. Weber | Fri, 5 Jan 2007 | 12:44pm |
| FW: Glaucous-winged age | Lethaby, Nick | Fri, 5 Jan 2007 | 2:00pm |
| Re: Glaucous-winged age | Alvaro Jaramillo | Fri, 5 Jan 2007 | 4:17pm |
| 3rd-year Glaucous-wings | Alan Contreras | Fri, 5 Jan 2007 | 7:58pm |
| Re: Blackpoll vs Bay-breasted (long) | David Seibel | Fri, 5 Jan 2007 | 8:05pm |
| Re: seeking feedback on two more gulls -
clarification and more | Martin Reid | Fri, 5 Jan 2007 | 9:10pm |
| Interesting gull in Michigan | Allen Chartier | Sat, 6 Jan 2007 | 7:59am |
| Re: Interesting gull in Michigan | Dick Newell | Sat, 6 Jan 2007 | 9:36am |
| Re: Interesting gull in Michigan | Ottavio Janni | Sat, 6 Jan 2007 | 9:48am |
| Re: Interesting gull in Michigan | Bruce Mactavish | Sat, 6 Jan 2007 | 1:13pm |
| Re: "Glaucous-winged" Gull in Gloucestershire | Martin Reid | Sat, 6 Jan 2007 | 2:11pm |
| Re: Interesting gull in Michigan | Allen Chartier | Sat, 6 Jan 2007 | 2:53pm |
| Re: Interesting gull in Michigan | Robert Wallace | Sat, 6 Jan 2007 | 3:28pm |
| Re: Interesting gull in Michigan | Mars Muusse | Sat, 6 Jan 2007 | 5:05pm |
| Re: Glaucous-winged age | Norman D.van Swelm | Sat, 6 Jan 2007 | 5:44pm |
| Re: Glaucous-winged age | Norman D.van Swelm | Sat, 6 Jan 2007 | 6:13pm |
| Re: Glaucous-winged age | Norman D.van Swelm | Sat, 6 Jan 2007 | 6:26pm |
| Re: Glaucous-winged age | Norman D.van Swelm | Sat, 6 Jan 2007 | 6:42pm |
| Re: Glaucous-winged age | Alvaro Jaramillo | Sat, 6 Jan 2007 | 6:55pm |
|
To use email addresses replace '(AT)' with '@'.
This is done to confuse the spam 'bots.
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[ << | >> | ^^ ]
Subject: "Ipswich" Savannah Sparrow
From: gdentremont(AT)JUNO.COM
Date: 1 Jan 2007 8:40pm
On Nantucket Island, MA December 31, 2006 I observed three Savannah
Sparrow; two of which were larger and paler. This was in a cranberry bog
edge habitat; not on a coastal sand dune. This is between one and two
miles from the coast. I have never encountered Ipswich away from coastal
dune or grassy habitat.
These two birds showed an overall paler gray than the third bird (direct
comparison-there were 5 other Savannahs which looked like the expected
Savannah Sparrows) with noticeable pale offwhite braces which were not
present on the third bird. If these birds were on the dunes, then I
would say they were definitely Ipswich. However, I could not see the
rufous bend in the wing ("shoulder") and there was a size difference
between the two pale birds; even though the two of them were larger than
the third. (Even though not directly compared, these two appeared larger
than the other five in the area.)
I can not located adequate images/photos which shows several backs of
known Ipswich. My question: Is the whitish braces on the back with the
grayish background color and pale faces definitive of Ipswich?
Many thanks.
Glenn
Glenn d'Entremont
gdentremont(AT)juno.com
Stoughton, MA
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Subject: Re: Redpoll ID challenge
From: Jeff Bouton <jbouton2(AT)EARTHLINK.NET>
Date: 2 Jan 2007 7:58am
When banding Redpolls in Fairbanks, Alaska in winter I'd see at least 1 bird
in 20 to 30 that was intermediate in plumage like the bird shown. We'd catch
as many as a few hubdred redpolls in just a few hours so I had opportunities
to handle, measure, and observe many of these birds. When I first encoutered
this range of variation, I went to the UAF museum in hopes of getting to the
bottom of this only to learn that in their collection they had entire trays
of birds that were simply "Redpolls".... So, unfortunately, this is not an
uncommon dilemna and perhaps not surprising since these birds do appear
together in parts of their breeding range, have similar if not the same
calls and songs (at least from my experience), and seem to overlap on ALL of
the known marking differences. Like Mike, when push came to shove I also
felt that bill shape and measurement was the most consistent feature on
these confusing species. As such I'd probably lean toward a lightly marked
Common Redpoll here if forced to put a name to it, assuming these two REALLY
deserve separate species treatment anyway.
The flip side of this was darker birds that had perfect Hoary bills. It
seemed that these were typically young birds as well, with buff wash. I
recaptured a bird banded (not by me happily) as an immature Common that had
transformed into a picture perfect Hoary by the following winter. So I
suspect in this cautionary tale (or is ot undertail) I'd suggest that not
only can you bump into light birds that appear to be Common otherwise, but
you may also see darker immature birds that have Hoary-esque bills.
At any rate, after years of seeing these beasts up close and personal I'm
beginning to prefer the much simpler "Redpoll"! ;)
Good birding and Happy Holidays,
Jeff Bouton
Florida
(formerly Fairbanks, AK now enjoying my warmer green holiday season!)
jbouton2(AT)earthlink.net
----- Original Message -----
From: "Mike Kirch" <asioflammeus(AT)NEW.RR.COM>
To: <BIRDWG01(AT)LISTSERV.ARIZONA.EDU>
Sent: Saturday, December 30, 2006 12:03 PM
Subject: Re: [BIRDWG01] Redpoll ID challenge
> This is an interesting bird. I think one should look at the overall shape
of
> the bird in determining Common and Hoary Redpoll species. Redpolls are
> notorious for their plumage variability and the first thing I try to look
at
> when seeing a lightly marked Redpoll is bill size and shape. Pics one and
> three seem to show the overall longer bill of Common versus the stubby
bill
> of a Hoary. The head seems stretched out from the body, ie. there appears
to
> be some length to the neck. Hoary strikes me as thick-necked without much
> elongation.
>
> The overall plumage is indeed light, however the lack of light coloration
on
> the scapulars is troubling for Hoary. I've seen quite a few otherwise good
> Common Redpolls that are similar to this bird in overall plumage, in
> particular the light amount of pink on the breast and the light streaking
on
> the sides. The UNTACS are very lightly marked but this is the only feature
I
> see in favor of Hoary. I believe the most important plumage feature to
> consider is the lightness of the scapulars, not necessarily the amount of
> pink or flank streaking as this is so variable. This bird shows scapulars
in
> the range of Common.
>
> Here's an interesting article from SORA about plumage variability in
> Redpolls from Manitoba.
> http://elibrary.unm.edu/sora/search.php
>
> I believe this bird is a lightly marked Common Redpoll based on bill size
> and shape, elongated head and neck and darker scapular feathers.
>
> Mike Kirch
> Appleton WI
>
>
> ----- Original Message -----
> From: "Mark Brown" <markb249(AT)EXCITE.COM>
> To: <BIRDWG01(AT)LISTSERV.ARIZONA.EDU>
> Sent: Saturday, December 30, 2006 1:25 AM
> Subject: [BIRDWG01] Redpoll ID challenge
>
>
> > Birders,
> >
> > There is a redpoll that has been photographed in central Iowa recently
> > that seems to have features of both Common and Hoary. Click on the
> > following link:
> >
> > http://www.iowabirds.org/photo-gallery/
> >
> > Under the "ID Help Needed" are 4 Redpoll photos that I took on Christmas
> > Eve, and under the "Rare Birds" folder are two more photos that Ann
> > Johnson took of the same bird on December 29. We're very intersted in
any
> > opinions. Thank you!
> >
> > Mark Brown
> > Iowa City
> >
> >
> >
> > _______________________________________________
> > Join Excite! - http://www.excite.com
> > The most personalized portal on the Web!
> >
> >
> > Join or Leave BIRDWG01:
> > http://listserv.arizona.edu/cgi-bin/wa?SUBED1=birdwg01
> >
> > Archives: http://listserv.arizona.edu/archives/birdwg01.html
> >
>
>
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[ << | >> | ^^ ]
Subject: Re: "Ipswich" Savannah Sparrow
From: "Ian A. McLaren" <I.A.McLaren(AT)Dal.Ca>
Date: 2 Jan 2007 9:06am
Hi Glenn et al.:
There are a few photos of both "Ipswich" and mainland Savannah Sparrows in the
recent article on the former in "Birding" by me and Andy Horn. There are more
to be googled.
I a bit puzzled by the consideration of "whitish braces on the back as a
distinguishing feature, as both forms show these to varying degrees.
Certainly the two larger, grayish birds described by Glenn would seem good for
"Ipswich," but Basic I "Ipswich" can be quite brownish and darker, as shown by
the introductory photo in the above article. I would hesitate to call Glen's
smaller, darker bird without seeing it or a photo.
As for habitat choices, during our survey eons ago along the US East Coast we
found "Ipswich" almost exclusively in the outer dunes, but not always - the
occasional bird was found in the wetland, heathy, or brushy inland parts of
beaches. During migration, they can occur widely - I've seen two in my
downtown backyard in Halifax, NS.
Finally, here's another plea for those who savour the exhilaration of
the outer
beaches this winter. Please keep your eyes open and report to me any banded
"Ipswiches" (aluminum and colour combinations and positions). This is for a
student of a colleague.
Cheers, Ian
Ian A. McLaren
Biology Department
Dalhousie University
Halifax, NS Canada B3H 4J1
> Quoting gdentremont(AT)JUNO.COM:
> I can not located adequate images/photos which shows several backs of
> known Ipswich. My question: Is the whitish braces on the back with the
> grayish background color and pale faces definitive of Ipswich?
>
> Many thanks.
>
> Glenn
>
> Glenn d'Entremont
> gdentremont(AT)juno.com
> Stoughton, MA
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[ << | >> | ^^ ]
Subject: FWD: Peregrine Falcon deduction / identification
using reactions of other birds
From: Nate Dias <offshorebirder(AT)YAHOO.COM>
Date: 3 Jan 2007 2:57pm
I do not know if this is off-topic for ID-Frontiers,
but the following post concerns raptor identification
without seeing or hearing the bird in question.
While the 'method' is not suitable for 100% positive
IDs, I have never ended up being mistaken when saying
out loud to a birding group "there HAS to be a
Peregrine making that happen".
Forgive me if this is a "duh" kind of tip that
everyone figured out long ago...
Nate Dias
----------------------------------------
Subject: Peregrine Falcon deduction / identification
using reactions of other birds
From: Nate Dias <offshorebirder AT yahoo.com>
To: Carolinabirds(AT)duke.edu
Date: Wed, 3 Jan 2007 13:39:23 -0800 (PST)
On New Year's Day, I had the good fortune of birding
Alligator River NWR in Dare County, North Carolina.
An added treat was being introduced to its winter
wonders by Ricky Davis and Jeff Lewis.
At one point, Ricky and I were birding on Link Road
and we saw a wide area of airspace near some distant
impoundments become instantly filled with clouds of
waterfowl. This happened twice in a 2-3 minute
period.
From this I deduced the likely presence of a Peregrine
Falcon, since (in my experience) waterfowl react in a
different way to Eagles, humans and other
disturbances. For instance, when an Eagle shows up,
birds tend to begin flushing from the side of the
impoundment near the Eagle. Same with a human
appearing in their field of view. The birds tend to
take flight in a wave that moves from the disturbance
outward. Or else the birds nearest the threat flush
first, followed by everyone else.
But when a Peregrine shows up, it is like the
'Keystone Cops', as if the entire assemblage
collectively says "Oh lordy, it's a Peregrine -
scram!" I suppose this is because no potential prey
that a Peregrine can see is safe - unlike with an
Eagle, Human, Coyote, etc.
In areas with mixed shorebirds, ducks and gulls, you
can tell when it's a Peregrine and not a Merlin
flushing things, because Gulls and larger ducks do not
take off for a Merlin.
This method isn't foolproof, but with experience, one
can often call Peregrine Falcons before they are
sighted.
It turned out to be the case Monday - the Peregrine
flew by as I was speed walking down Link Road over to
Gadwall Road where Jeff had the Swainson's Hawk staked
out.
Nathan Dias - Charleston, SC
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Subject: seeking feedback on two more gulls
From: Martin Reid <upupa(AT)AIRMAIL.NET>
Date: 3 Jan 2007 8:16pm
Dear All,
Here are two more LBBG-types from Texas that I feel are unusual; I'd
appreciate feedback from those with more experience of the various
forms of LBBG - thanks:
http://www.martinreid.com/Gull%20website/gullsp165.html
http://www.martinreid.com/Gull%20website/gullsp164.html
- LBBGs seem to be increasing here, and perhaps what i am seeing is
the extra variation expected when the sample size rises - ?
Cheers,
Martin
--
>Martin Reid
>San Antonio, Texas
>mailto:upupa(AT)airmail.net
>http://www.martinreid.com
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[ << | >> | ^^ ]
Subject: Glaucous-winged Gull in Gloucester, UK
From: Dick Newell <dick.newell(AT)ZEN.CO.UK>
Date: 4 Jan 2007 6:48am
Re: http://www.birdingworld.co.uk/StopPress1.htm
Although I have had absolutely nothing to do with this bird, being a Brit,
with limited experience of Glaucous-winged Gull, and none recently, I would
welcome Western US comment. I have had a fairly thorough trawl of the
internet, O&L and Grant, and I cannot find anything that quite matches its
extraordinary appearance. Let's hope there is a DNA sample.
Dick Newell
Cambridge, UK
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[ << | >> | ^^ ]
Subject: Re: Glaucous-winged Gull in Gloucester, UK
From: sgmlod(AT)AOL.COM
Date: 4 Jan 2007 9:00am
----INCLUDING text/plain MIME SECTION----
Greetings All
I am unfortunately quite familiar with this bird. Go to my local parking lot,
and I can find you several.
I'd call this a GW x Western Gull.
This, of course, could be argued - where does one draw the line between "pure"
and hybrid.
The wingtips and mantle both look a bit dark for a "pure" GWGU to me.
Supposedly, hybrids tend to look more like GWGU than WEGU on average.
I'd expect a HEGU x GWGU to show a paler mantle and a more HEGU like structure.
Cheers
Steve Mlodinow
-----Original Message-----
From: dick.newell(AT)ZEN.CO.UK
To: BIRDWG01(AT)LISTSERV.ARIZONA.EDU
Sent: Thu, 4 Jan 2007 5:49 AM
Subject: [BIRDWG01] Glaucous-winged Gull in Gloucester, UK
Re: http://www.birdingworld.co.uk/StopPress1.htm
Although I have had absolutely nothing to do with this bird, being a Brit,
with limited experience of Glaucous-winged Gull, and none recently, I would
welcome Western US comment. I have had a fairly thorough trawl of the
internet, O&L and Grant, and I cannot find anything that quite matches its
extraordinary appearance. Let's hope there is a DNA sample.
Dick Newell
Cambridge, UK
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Archives: http://listserv.arizona.edu/archives/birdwg01.html
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[ << | >> | ^^ ]
Subject: Re: Glaucous-winged Gull in Gloucester, UK
From: "Lethaby, Nick" <nlethaby(AT)TI.COM>
Date: 4 Jan 2007 9:11am
This is a multi-part message in MIME format.
----INCLUDING text/plain MIME SECTION----
All:
=20
I'm not sure we can say where a pure GW ends and a hybrid starts in
terms of wing-tip color. I do agree this looks a bit dark though.
However there is clinal variation in the darkness of GWGU wing-tips.
Certainly birds wintering in Japan often look darker-winged those I see
wintering in S. Cal.
=20
Nick Lethaby
DSP/BIOS Product Manager
Software Development Systems
Texas Instruments
805 562 5106
nlethaby(AT)ti.com
=20
________________________________
From: NBHC ID-FRONTIERS Frontiers of Field Identification
[mailto:BIRDWG01(AT)LISTSERV.ARIZONA.EDU] On Behalf Of sgmlod(AT)AOL.COM
Sent: Thursday, January 04, 2007 8:00 AM
To: BIRDWG01(AT)LISTSERV.ARIZONA.EDU
Subject: Re: [BIRDWG01] Glaucous-winged Gull in Gloucester, UK
=20
Greetings All
=20
I am unfortunately quite familiar with this bird. Go to my local parking
lot, and I can find you several.
I'd call this a GW x Western Gull.
=20
This, of course, could be argued - where does one draw the line between
"pure" and hybrid.
=20
The wingtips and mantle both look a bit dark for a "pure" GWGU to me.
Supposedly, hybrids tend to look more like GWGU than WEGU on average.=20
=20
I'd expect a HEGU x GWGU to show a paler mantle and a more HEGU like
structure.
=20
Cheers
Steve Mlodinow=20
=20
-----Original Message-----
From: dick.newell(AT)ZEN.CO.UK
To: BIRDWG01(AT)LISTSERV.ARIZONA.EDU
Sent: Thu, 4 Jan 2007 5:49 AM
Subject: [BIRDWG01] Glaucous-winged Gull in Gloucester, UK
Re: http://www.birdingworld.co.uk/StopPress1.htm
=20
Although I have had absolutely nothing to do with this bird, being a
Brit,
with limited experience of Glaucous-winged Gull, and none recently, I
would
welcome Western US comment. I have had a fairly thorough trawl of the
internet, O&L and Grant, and I cannot find anything that quite matches
its
extraordinary appearance. Let's hope there is a DNA sample.
Dick Newell
Cambridge, UK
=20
=20
Join or Leave BIRDWG01:
http://listserv.arizona.edu/cgi-bin/wa?SUBED1=3Dbirdwg01
=20
Archives: http://listserv.arizona.edu/archives/birdwg01.html
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[ << | >> | ^^ ]
Subject: Re: Glaucous-winged Gull in Gloucester, UK
From: Alan Contreras <acontrer(AT)MINDSPRING.COM>
Date: 4 Jan 2007 9:25am
Because they are part of the northwest coast complex, one can always wonder
about the provenance of a specific Glaucous-wing. However, I don't see
anything on this bird that a 2nd winter G-wing *could not* have. G-wings are
quite variable, even in size and coloration. It is slightly dark, but I
emphasize slightly.
--
Alan Contreras
EUGENE, OREGON
acontrer(AT)mindspring.com
> From: Dick Newell <dick.newell(AT)ZEN.CO.UK>
> Reply-To: Dick Newell <dick.newell(AT)ZEN.CO.UK>
> Date: Thu, 4 Jan 2007 13:49:16 +0000
> To: <BIRDWG01(AT)LISTSERV.ARIZONA.EDU>
> Subject: [BIRDWG01] Glaucous-winged Gull in Gloucester, UK
>
> Re: http://www.birdingworld.co.uk/StopPress1.htm
>
> Although I have had absolutely nothing to do with this bird, being a Brit,
> with limited experience of Glaucous-winged Gull, and none recently, I would
> welcome Western US comment. I have had a fairly thorough trawl of the
> internet, O&L and Grant, and I cannot find anything that quite matches its
> extraordinary appearance. Let's hope there is a DNA sample.
> Dick Newell
> Cambridge, UK
>
>
> Join or Leave BIRDWG01:
http://listserv.arizona.edu/cgi-bin/wa?SUBED1=birdwg01
>
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[ << | >> | ^^ ]
Subject: Re: Glaucous-winged Gull in Gloucester, UK
From: Phil Pickering <philliplc(AT)CHARTER.NET>
Date: 4 Jan 2007 10:37am
http://www.birdingworld.co.uk:80/StopPress1.htm
Very interesting bird in that it structurally looks within typical range
of G-w. Also considering the primaries probably aren't fully mature
I'm not sure they are necessarily too dark, at least not obviously so.
However the darkish, solidly filled-in nature of the underparts continuing
down from the hood strikes me as very unusual for such a mature G-w
(I assume probably 3rd-basic since it shows developed apical spots and
advanced maturity in coverts/tertials). In my recollection G-w of this age
much more typically show a more hooded look, with clean or at worst
thinly blotchy underparts. I will have to look at a few more of this age
when I get the chance, but it doesn't inspire confidence in it being pure.
Also I'm not sure how often 3rd-basic G-w show developed apical
spots, another thing to check out. Overall the level of maturity in
various features seems oddly mismatched, even considering typical
variability.
Also, while not definitive, it does seem to lack what would be confidence
inspiring fine closely-spaced latitudinal streaking anywhere in the hood.
Cheers,
Phil Pickering
Lincoln City, Oregon
philliplc(AT)charter.net
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Subject: Re: Glaucous-winged Gull in Gloucester, UK
From: Alvaro Jaramillo <chucao(AT)COASTSIDE.NET>
Date: 4 Jan 2007 10:58am
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Folks
Another vote for you can't tell where hybrids start and Glaucous-wings
end, but this bird is on the dark side of Glaucous-winged. I echo Alan's
point that Glaucous-wings are variable, at least a winter concentration of
them is very, very variable even just looking at pale winged birds. The fact
that the bird is in its second cycle makes the dark primaries a bit less
troublesome to me, although the classic second year Glaucous-winged has
paler primaries than this. The reason is that second cycle birds, in most
large gulls, have more extensive and often darker tail and primary markings
than either the third or first cycles. This is most obvious in species which
start out pale winged in the first cycle, such as Glaucous-winged and
Thayer's. Second cycle Thayer's are often black tailed and have extensive
black on upperside of primaries, much more so than in any subsequent age.
Similarly Glaucous-wings sometimes show this pattern as well, with rather
dark grey primaries and tail contrasting with the rest of the body. Of
course these could all be hybrids.
The British bird could be identified as a Glaucous-winged and I would buy
that, one could propose a hybrid as well, and you would have a good argument
although a difficult one to prove. There are photos of Glaucous-wings from
Japan (as Nick mentions) which are quite dark winged and these certainly are
not Western x Glaucous-winged hybrids, and I do not expect a Herring x
Glaucous-winged to look like the British bird so the cleanest solution given
the data is to call that bird a Glaucous-wing. Not a classic one, but within
the range of variation.
I hope they did keep some blood or feathers. Although if they look at mtDNA
and find Glaucous-winged it only tells you what the mother was, we would not
have resolved the hybrid issue. I am not sure if anyone has published on
nuclear DNA relationships within gulls, maybe some of the folks who know
what they are talking about can answer that.
Cheers
Alvaro
Alvaro Jaramillo
chucao(AT)coastside.net
Half Moon Bay, California
Field Guides - Birding Tours Worldwide
www.fieldguides.com
_____
From: NBHC ID-FRONTIERS Frontiers of Field Identification
[mailto:BIRDWG01(AT)LISTSERV.ARIZONA.EDU] On Behalf Of Lethaby, Nick
Sent: Thursday, January 04, 2007 8:10 AM
To: BIRDWG01(AT)LISTSERV.ARIZONA.EDU
Subject: Re: [BIRDWG01] Glaucous-winged Gull in Gloucester, UK
All:
I'm not sure we can say where a pure GW ends and a hybrid starts in terms of
wing-tip color. I do agree this looks a bit dark though. However there is
clinal variation in the darkness of GWGU wing-tips. Certainly birds
wintering in Japan often look darker-winged those I see wintering in S. Cal.
Nick Lethaby
DSP/BIOS Product Manager
Software Development Systems
Texas Instruments
805 562 5106
nlethaby(AT)ti.com
_____
From: NBHC ID-FRONTIERS Frontiers of Field Identification
[mailto:BIRDWG01(AT)LISTSERV.ARIZONA.EDU] On Behalf Of sgmlod(AT)AOL.COM
Sent: Thursday, January 04, 2007 8:00 AM
To: BIRDWG01(AT)LISTSERV.ARIZONA.EDU
Subject: Re: [BIRDWG01] Glaucous-winged Gull in Gloucester, UK
Greetings All
I am unfortunately quite familiar with this bird. Go to my local parking
lot, and I can find you several.
I'd call this a GW x Western Gull.
This, of course, could be argued - where does one draw the line between
"pure" and hybrid.
The wingtips and mantle both look a bit dark for a "pure" GWGU to me.
Supposedly, hybrids tend to look more like GWGU than WEGU on average.
I'd expect a HEGU x GWGU to show a paler mantle and a more HEGU like
structure.
Cheers
Steve Mlodinow
-----Original Message-----
From: dick.newell(AT)ZEN.CO.UK
To: BIRDWG01(AT)LISTSERV.ARIZONA.EDU
Sent: Thu, 4 Jan 2007 5:49 AM
Subject: [BIRDWG01] Glaucous-winged Gull in Gloucester, UK
Re: http://www.birdingworld.co.uk/StopPress1.htm
Although I have had absolutely nothing to do with this bird, being a Brit,
with limited experience of Glaucous-winged Gull, and none recently, I would
welcome Western US comment. I have had a fairly thorough trawl of the
internet, O&L and Grant, and I cannot find anything that quite matches its
extraordinary appearance. Let's hope there is a DNA sample.
Dick Newell
Cambridge, UK
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Subject: Re: Glaucous-winged Gull in Gloucester, UK
From: Alvaro Jaramillo <chucao(AT)COASTSIDE.NET>
Date: 4 Jan 2007 11:03am
Phil
I had looked at the photos and thought second cycle, but you might be
right it may be a third. Aging Glaucous-wings seems to be much less straight
forward than aging Westerns it seems to me. If it is an advanced looking
second cycle (how would one know?) then the more extensive dark on the body
may not be so hard to understand. Maybe there are photos of spread wing,
rump and tail to look at?
Cheers
Alvaro
Alvaro Jaramillo
chucao(AT)coastside.net
Half Moon Bay, California
Field Guides - Birding Tours Worldwide
www.fieldguides.com
-----Original Message-----
From: NBHC ID-FRONTIERS Frontiers of Field Identification
[mailto:BIRDWG01(AT)LISTSERV.ARIZONA.EDU] On Behalf Of Phil Pickering
Sent: Thursday, January 04, 2007 9:38 AM
To: BIRDWG01(AT)LISTSERV.ARIZONA.EDU
Subject: Re: [BIRDWG01] Glaucous-winged Gull in Gloucester, UK
http://www.birdingworld.co.uk:80/StopPress1.htm
Very interesting bird in that it structurally looks within typical range
of G-w. Also considering the primaries probably aren't fully mature
I'm not sure they are necessarily too dark, at least not obviously so.
However the darkish, solidly filled-in nature of the underparts continuing
down from the hood strikes me as very unusual for such a mature G-w
(I assume probably 3rd-basic since it shows developed apical spots and
advanced maturity in coverts/tertials). In my recollection G-w of this age
much more typically show a more hooded look, with clean or at worst
thinly blotchy underparts. I will have to look at a few more of this age
when I get the chance, but it doesn't inspire confidence in it being pure.
Also I'm not sure how often 3rd-basic G-w show developed apical
spots, another thing to check out. Overall the level of maturity in
various features seems oddly mismatched, even considering typical
variability.
Also, while not definitive, it does seem to lack what would be confidence
inspiring fine closely-spaced latitudinal streaking anywhere in the hood.
Cheers,
Phil Pickering
Lincoln City, Oregon
philliplc(AT)charter.net
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Subject: Re: Glaucous-winged Gull in Gloucester, UK
From: Phil Pickering <philliplc(AT)CHARTER.NET>
Date: 4 Jan 2007 12:04pm
I am assuming retarded maturity is more likely than advanced, but
Alvaro is correct - no way to know. Either way it's odd enough
where I would hesitate to say this bird's appearance is within the
typical range of G-w.
It may be worth restating the usual speculation that apparent phenotypical
abormality may be tied genetically to extreme vagrancy, either in hybrids
and/or in genetically aberrant "pure" birds.
Cheers,
Phil
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Subject: Japanese GWGUs
From: sgmlod(AT)AOL.COM
Date: 4 Jan 2007 12:37pm
----INCLUDING text/plain MIME SECTION----
Greetings All
One possibility on Japanese GWGUs....
I don't know what percent show darker mantles and/or wings than North American
birds. If the percentage is not huge, one possibility is that some of these
birds are GW x SBGU.
Just another cheery thought
Cheers
Steven Mlodinow
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Subject: Re: Japanese GWGUs
From: "Lethaby, Nick" <nlethaby(AT)TI.COM>
Date: 4 Jan 2007 12:43pm
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All:
=20
In Hokkaido, the wintering GWGUs were pretty uniform in appearance and
quite common so I don't believe that SBGU hybridization has necessarily
caused the darker wing-tips.
=20
SBGU and GWGU definitely interbreed regularly but the number of hybrid
pairs is low because GWGUs breed through to the Commander Islands but
don't reach the mainland. Therefore hybridization in limited to a few
SBGUs reaching the Commanders and to odd GWGUs that remain on the
mainland of Russia in the summer. I've only seen one likely hybrid in
Japan in winter.
=20
Nick Lethaby
DSP/BIOS Product Manager
Software Development Systems
Texas Instruments
805 562 5106
nlethaby(AT)ti.com
=20
________________________________
From: NBHC ID-FRONTIERS Frontiers of Field Identification
[mailto:BIRDWG01(AT)LISTSERV.ARIZONA.EDU] On Behalf Of sgmlod(AT)AOL.COM
Sent: Thursday, January 04, 2007 11:37 AM
To: BIRDWG01(AT)LISTSERV.ARIZONA.EDU
Subject: [BIRDWG01] Japanese GWGUs
=20
Greetings All
=20
One possibility on Japanese GWGUs....
=20
I don't know what percent show darker mantles and/or wings than North
American birds. If the percentage is not huge, one possibility is that
some of these birds are GW x SBGU.
=20
Just another cheery thought
=20
Cheers
Steven Mlodinow=20
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Subject: Re: Glaucous-winged Gull in Gloucester, UK
From: Lee Evans <LGREUK400(AT)AOL.COM>
Date: 4 Jan 2007 2:55pm
----INCLUDING text/plain MIME SECTION----
Alan/Steve
Do you not think that this bird is a 3rd-winter?
Best wishes
Lee G R Evans
British Birding Association
UK400 Club, Rare Birds Magazine, Ornithological Consultant and Conservationist
Discussion Forum/Email Group: _http://groups.yahoo.com/group/UK400Club/_
(http://groups.yahoo.com/group/UK400Club/)
Email Address: LGREUK400(AT)aol.com
Website Address: _www.uk400clubonline.co.uk_
(http://www.uk400clubonline.co.uk/)
8 Sandycroft Road
Little Chalfont
Amersham
Buckinghamshire
England
HP6 6QL
Telephones: 01494 763010 and 01494 581157
Mobile/Text Alerts: 07881 906629
(Lee Evans Enterprises incorporate documentation of rare bird occurrences in
Britain & Ireland and elsewhere in the Western Palearctic and in North
America; Rare Bird Information and Rare Bird Alerts; Rare Birds Magazine and
other
related publications; Bird Tours for Birders; also Mobile Discos (Nighthawk
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Subject: Re: Glaucous-winged Gull in Gloucester, UK
From: Alan Contreras <acontrer(AT)mindspring.com>
Date: 4 Jan 2007 3:21pm
<HEAD>
<META content=3D"MSHTML 6.00.2800.1586" name=3DGENERATOR></HEAD>
<BODY>
<DIV>Some of us on the west coast are having an interesting discussion as t=
o whether this is a second- or third-winter bird. The fact that sever=
al people with quite a bit of gull knowledge (and extensive daily experienc=
e with Glaucous-wings) initially split pretty evenly on its age suggests so=
me of the complexities of ageing this species. <BR><BR><BR>
<BLOCKQUOTE style=3D"PADDING-LEFT: 5px; MARGIN-LEFT: 0px; BORDER-LEFT: #000=
0ff 2px solid">-----Original Message----- <BR>From: Lee Evans <LGREUK400@AO=
L.COM><BR>Sent: Jan 4, 2007 1:54 PM <BR>To: BIRDWG01(AT)LISTSERV.ARIZONA.EDU <=
BR>Subject: Re: [BIRDWG01] Glaucous-winged Gull in Gloucester, UK <BR><BR><=
ZZZHTML><ZZZHEAD><ZZZMETA content=3D"text/html; charset=3DUS-ASCII" http-eq=
uiv=3D"Content-Type"><ZZZMETA content=3D"MSHTML 5.50.4611.1300" name=3D"GEN=
ERATOR"></ZZZHEAD><ZZZBODY id=3Drole_body style=3D"FONT-SIZE: 10pt; COLOR: =
#000000; FONT-FAMILY: Arial" rightMargin=3D"7" topMargin=3D"7" leftMargin=
=3D"7" bottomMargin=3D"7"><FONT id=3Drole_document face=3DArial color=3D#00=
0000 size=3D2>
<DIV>Alan/Steve</DIV>
<DIV> </DIV>
<DIV>Do you not think that this bird is a 3rd-winter?</DIV>
<DIV> </DIV>
<DIV>Best wishes=20
<DIV> </DIV>
<DIV><FONT lang=3D0 face=3DArial size=3D2 FAMILY=3D"SANSSERIF" PTSIZE=3D"10=
">Lee G R Evans<BR>British Birding Association<BR>UK400 Club, Rare Birds Ma=
gazine, Ornithological Consultant and Conservationist<BR>Discussion Forum/E=
mail Group: <A href=3D"http://groups.yahoo.com/group/UK400Club/">http://gro=
ups.yahoo.com/group/UK400Club/</A><BR>Email Address: LGREUK400(AT)aol.com<BR>W=
ebsite Address: <A href=3D"http://www.uk400clubonline.co.uk/">www.uk400club=
online.co.uk</A><BR><BR>8 Sandycroft Road<BR>Little Chalfont<BR>Amersham<BR=
>Buckinghamshire<BR>England<BR>HP6 6QL<BR>Telephones: 01494 763010 and 0149=
4 581157<BR>Mobile/Text Alerts: 07881 906629<BR>(Lee Evans Enterprises inco=
rporate documentation of rare bird occurrences in Britain & Ireland and=
elsewhere in the Western Palearctic and in North America; Rare Bird Inform=
ation and Rare Bird Alerts; Rare Birds Magazine and other related publicati=
ons; Bird Tours for Birders; also Mobile Discos (Nighthawk Roadshow); CD Vi=
nyl & DVD Sales; Haynes Car Manuals For Sale; Prestige Car Delivery; UK=
Courier and Road Traffic Officing)</FONT></DIV></DIV></FONT></ZZZBODY></ZZ=
ZHTML>
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<P></P></BLOCKQUOTE></DIV></BODY><PRE>
Alan Contreras - Eugene, Oregon</PRE>
<p>
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Subject: Glaucous-winged age
From: Alvaro Jaramillo <chucao(AT)COASTSIDE.NET>
Date: 5 Jan 2007 12:09am
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Folks
I set up a quickie web page with various immature Glaucous-winged Gulls
with some guesses as to ages.
http://www.coastside.net/chucao/gulls/Glaucous-winged.htm
Now look at my page with known age banded Western Gulls:
http://www.coastside.net/chucao/gulls/wegu-age.htm
If these are a good model to use for Glaucous-winged, then only the very
adult like birds are the third cycles.
Comments, thoughts? It is an interesting exercise in the more you look, the
less clear the picture becomes.
Cheers
Alvaro
Alvaro Jaramillo
chucao(AT)coastside.net
Half Moon Bay, California
Field Guides - Birding Tours Worldwide
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Subject: Re: Glaucous-winged age
From: Dick Newell <dick.newell(AT)ZEN.CO.UK>
Date: 5 Jan 2007 2:34am
> This message is in MIME format. Since your mail reader does not understand
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I originally posted this bird, because I could not find a picture matching
it, and in particular, I could not reconcile the apparently 3rd basic
features (extensive grey in the wing-coverts and tertials, large white
apical tips on the primaries) with what looked like features from a younger
bird (much dark in the bill, extensive smooth grey-brown on the head and
underparts). Alvaro=B9s 3rd cycle pictures are consistent with the former, bu=
t
not the latter.
One likes one=B9s vagrants (particularly a first for Europe) to look
=B3normal=B2=
.
Phil Pickering asserted =8Capparent phenotypical abormality may be tied
genetically to extreme vagrancy, either in hybrids and/or in genetically
aberrant "pure" birds=B9.
Is this because hybrid genes cause abnormal migration patterns, or are
unusual moult sequences caused by birds ending up in a strange environment?
Just how abnormal is the plumage of this bird? For those who have these
things strutting about in their car parks, how difficult is it to find one
looking like this bird - whether pure or hybrid? If they are rare, should w=
e
be looking at the other side of the Pacific divide for the origins of this
bird?
Dick
Cambridge, UK
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Subject: Re: Glaucous-winged age
From: "Norman D.van Swelm" <Norman.vanswelm(AT)wxs.nl>
Date: 5 Jan 2007 9:30am
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Re: [BIRDWG01] Glaucous-winged age
Dick NeweI wrote: > One likes one's vagrants (particularly a first for
Europe) to look "normal". Phil Pickering asserted 'apparent phenotypical
abormality may be tied genetically to extreme vagrancy, either in hybrids and/or
in genetically aberrant "pure" birds'.
Is this because hybrid genes cause abnormal migration patterns, or are unusual
moult sequences caused by birds ending up in a strange environment? <
May I first wish all of you a very happy 2007?
As to Dick's question: the few sightings I have from my colo(u)r-ringed
hybrids are all within the normal migratory range of one of their parents and
indicate that migratory behaviour is heriditary. Extreme vagrancy is caused by
extreme atmospheric conditions.
If the Gloucestershire bird is indeed a Glaucous-winged Gull and I don't see
why not then it is not the first for Europe. The first was found in Switzerland
and, dare I say, the second was photographed by me on 5th December 1999 in The
Netherlands (pictures were shown on Martin Reid's gull-pages)! Like in 1999 the
present winter provides a sheer endless succession of storms from westerly
direcions on the Atlantic.
Norman
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Subject: Re: Glaucous-winged age
From: Lee Evans <LGREUK400(AT)AOL.COM>
Date: 5 Jan 2007 10:44am
----INCLUDING text/plain MIME SECTION----
Alvaro
I am no expert in North American gull ageing but my concern over the
Gloucester bird (currently being touted as a 2nd-winter) is that there is a
white
mirror on p10 (primary 10). In my opinion, this leans heavily towards the bird
being a retarded 3rd-winter but I would very much welcome comments from anyone
that spends time studying and photographing them. I am also in the process of
documenting this record and would very much appreciate any good images of first,
second, third and fourth winter birds from North America.
Furthermore, I was concerned that the Gloucester bird may well be a hybrid,
perhaps North American Herring x Glaucous Gull or North American Herring Gull x
Glaucous-winged Gull, but I hear that Steve Howell and others are happy that
the bird is a 'pure' GWG.
All the very best and many thanks for taking time to comment on this bird
Lee G R Evans
British Birding Association
UK400 Club, Rare Birds Magazine, Ornithological Consultant and Conservationist
Discussion Forum/Email Group: _http://groups.yahoo.com/group/UK400Club/_
(http://groups.yahoo.com/group/UK400Club/)
Email Address: LGREUK400(AT)aol.com
Website Address: _www.uk400clubonline.co.uk_
(http://www.uk400clubonline.co.uk/)
8 Sandycroft Road
Little Chalfont
Amersham
Buckinghamshire
England
HP6 6QL
Telephones: 01494 763010 and 01494 581157
Mobile/Text Alerts: 07881 906629
(Lee Evans Enterprises incorporate documentation of rare bird occurrences in
Britain & Ireland and elsewhere in the Western Palearctic and in North
America; Rare Bird Information and Rare Bird Alerts; Rare Birds Magazine and
other
related publications; Bird Tours for Birders; also Mobile Discos (Nighthawk
Roadshow); CD Vinyl & DVD Sales; Haynes Car Manuals For Sale; Prestige Car
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Subject: Re: Glaucous-winged age
From: Phil Pickering <philliplc(AT)CHARTER.NET>
Date: 5 Jan 2007 11:04am
> As to Dick's question: the few sightings I have from my colo(u)r-ringed
> hybrids are all within the normal migratory range of one of their parents
> and indicate that migratory behaviour is heriditary. Extreme vagrancy is
> caused by extreme atmospheric conditions.
Certainly much of vagrancy must be due to environmental conditions, but
I think you'd need a much, much larger sample size to make anything close
to the absolute statement Norm is making based on statistical correlation.
Obviously there are exponentially more hybrids than vagrants, and obviously
not all hybrids are vagrants. A percentage of hybrids making skewed
migrations due to genetic flaws small enough to be missed in a typical
banding survey, could still easily be large enough to account for a
significant percentage of vagrancy. Also isn't there a lot of evidence
some passerine vagrancy is due to genetic flaws?
This is pure speculation on my part, but it might account for why
apparent vagrant G-w east of the rockies seem to almost invariably have
fringe or atypical features. The same idea could also apply to genetically
flawed "pure" species - for example messed up maturity levels in the bird
in question possibly being genetically related to messed up directional
migration. The fact that most out-of-range G-w candidates seem to have
very dark-end primaries leads me to suspect the former is more likley.
Another possibility to consider is that at least some vagrant apparent
G-w-types may be previously undescribed hybrids of in-range species.
Or at least that possibility would need to be completely ruled out before
accepting a non-prototypical out-of-range G-w (see the European
"California" that fooled many of us a few years ago).
>Like in 1999 the present winter provides a sheer endless succession of
>storms from westerly direcions on the Atlantic.
Presumably the total percentage of gulls in the northwest Atlantic
available to be blown east by storms that also happen to be
Glaucous-winged is pretty small : ) If this bird showed up in the
company of dozens of smithsonianus that might make more sense.
If the bird in question is a G-w from normal range, some sort of reverse
migration over the polar regions might be a shorter path, particularly
for one originating in Siberia. Don't have a globe handy lol.
Cheers,
Phil
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Subject: Re: Glaucous-winged age
From: Phil Pickering <philliplc(AT)CHARTER.NET>
Date: 5 Jan 2007 11:15am
>For those who have these
things strutting about in their car parks, how difficult is it to find one
looking like this bird - whether pure or hybrid?
Looked at ~50 2nd/3rd-cycle yesterday, saw nothing close. Planning
to try again though.
Cheers,
Phil
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Subject: Re: Glaucous-winged age
From: Alvaro Jaramillo <chucao(AT)COASTSIDE.NET>
Date: 5 Jan 2007 11:41am
This is a multi-part message in MIME format.
----INCLUDING text/plain MIME SECTION----
Norman and Id Frontiers
Your comment (below) is very confusing to me. How does the pattern that
you are seeing show that migration is hereditary? The hybrid gulls could
very well be following flocks of one of the parental species, making the
pattern you see entirely environmental?
Of course any phenotypic trait (the expressed trait) is a combination of the
hereditary (genetic=genotype) component and the environmental component.
Even traits that we know (from studies) that have high heritability, like
height in people, can be drastically altered by the environment.
The way I interpreted the issue of hybrids being more prone to vagrancy is a
genetic argument, basically that the mix of different migratory patterns
from the adults will create a hybrid migratory pattern in the young which
may not be the same as that of either adult. I don't know that this is the
case in gulls, it is just how I express the argument that is commonly made
about hybrids. Of course the reality will not be simple because even if
migratory tendency is highly heritable, the environment will have a large
effect on the final outcome (the migration "phenotype") if we can call it
that.
Extreme vagrancy could also be caused by chance in some case, just plain old
chance.
Alvaro
Alvaro Jaramillo
chucao(AT)coastside.net
Half Moon Bay, California
Field Guides - Birding Tours Worldwide
www.fieldguides.com
_____
As to Dick's question: the few sightings I have from my colo(u)r-ringed
hybrids are all within the normal migratory range of one of their parents
and indicate that migratory behaviour is heriditary. Extreme vagrancy is
caused by extreme atmospheric conditions.
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Subject: Re: Glaucous-winged age
From: Lee Evans <LGREUK400(AT)AOL.COM>
Date: 5 Jan 2007 12:08pm
----INCLUDING text/plain MIME SECTION----
In a message dated 05/01/2007 16:31:27 GMT Standard Time,
Norman.vanswelm(AT)WXS.NL writes:
The first was found in Switzerland and,
Norman, I thought this record related to a ring only and no bird and when I
last investigated it, the thought was that the corpse may have dropped from the
undercarriage of an aircraft.
Best wishes
Lee G R Evans
British Birding Association
UK400 Club, Rare Birds Magazine, Ornithological Consultant and Conservationist
Discussion Forum/Email Group: _http://groups.yahoo.com/group/UK400Club/_
(http://groups.yahoo.com/group/UK400Club/)
Email Address: LGREUK400(AT)aol.com
Website Address: _www.uk400clubonline.co.uk_
(http://www.uk400clubonline.co.uk/)
8 Sandycroft Road
Little Chalfont
Amersham
Buckinghamshire
England
HP6 6QL
Telephones: 01494 763010 and 01494 581157
Mobile/Text Alerts: 07881 906629
(Lee Evans Enterprises incorporate documentation of rare bird occurrences in
Britain & Ireland and elsewhere in the Western Palearctic and in North
America; Rare Bird Information and Rare Bird Alerts; Rare Birds Magazine and
other
related publications; Bird Tours for Birders; also Mobile Discos (Nighthawk
Roadshow); CD Vinyl & DVD Sales; Haynes Car Manuals For Sale; Prestige Car
Delivery; UK Courier and Road Traffic Officing)
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Subject: Re: Glaucous-winged age
From: Lee Evans <LGREUK400(AT)AOL.COM>
Date: 5 Jan 2007 12:16pm
----INCLUDING text/plain MIME SECTION----
In a message dated 05/01/2007 18:05:44 GMT Standard Time,
philliplc(AT)CHARTER.NET writes:
Presumably the total percentage of gulls in the northwest Atlantic
available to be blown east by storms that also happen to be
Glaucous-winged is pretty small : ) If this bird showed up in the
company of dozens of smithsonianus that might make more sense.
If the bird in question is a G-w from normal range, some sort of reverse
migration over the polar regions might be a shorter path, particularly
for one originating in Siberia. Don't have a globe handy lol.
Hi Phil
White-winged gulls generally arrive in large numbers in Britain and Ireland
in late January/February, following gale-force Northwesterly winds. This winter
we have not had such conditions and as a result a paucity of both Glaucous
and Iceland Gulls. However, in mid December, we had an almost unprecedented
system arrive in from the Mid Atlantic and this produced record numbers of
Leach's
Petrels and somewhat surprisingly, single first-winter Ivory and Ross's
Gulls. I am presuming the GWG arrived under the same conditions.
Lee G R Evans
British Birding Association
UK400 Club, Rare Birds Magazine, Ornithological Consultant and Conservationist
Discussion Forum/Email Group: _http://groups.yahoo.com/group/UK400Club/_
(http://groups.yahoo.com/group/UK400Club/)
Email Address: LGREUK400(AT)aol.com
Website Address: _www.uk400clubonline.co.uk_
(http://www.uk400clubonline.co.uk/)
8 Sandycroft Road
Little Chalfont
Amersham
Buckinghamshire
England
HP6 6QL
Telephones: 01494 763010 and 01494 581157
Mobile/Text Alerts: 07881 906629
(Lee Evans Enterprises incorporate documentation of rare bird occurrences in
Britain & Ireland and elsewhere in the Western Palearctic and in North
America; Rare Bird Information and Rare Bird Alerts; Rare Birds Magazine and
other
related publications; Bird Tours for Birders; also Mobile Discos (Nighthawk
Roadshow); CD Vinyl & DVD Sales; Haynes Car Manuals For Sale; Prestige Car
Delivery; UK Courier and Road Traffic Officing)
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Subject: Re: Glaucous-winged age
From: "Lethaby, Nick" <nlethaby(AT)TI.COM>
Date: 5 Jan 2007 12:28pm
This is a multi-part message in MIME format.
----INCLUDING text/plain MIME SECTION----
All:
=20
I think the presumption that the GWGU arrived across the Atlantic is not
necessarily correct. It could have come through Arctic Russia. While
this isn't necessarily a likely route either, GWGUs are extremely rare
W. of the Rockies in the USA, rarer than species like California Gull or
even Slaty-backed Gull, neither of which has appeared in Europe to my
(limited) knowledge.
=20
Nick Lethaby
DSP/BIOS Product Manager
Software Development Systems
Texas Instruments
805 562 5106
nlethaby(AT)ti.com
=20
________________________________
From: NBHC ID-FRONTIERS Frontiers of Field Identification
[mailto:BIRDWG01(AT)LISTSERV.ARIZONA.EDU] On Behalf Of Lee Evans
Sent: Friday, January 05, 2007 11:16 AM
To: BIRDWG01(AT)LISTSERV.ARIZONA.EDU
Subject: Re: [BIRDWG01] Glaucous-winged age
=20
In a message dated 05/01/2007 18:05:44 GMT Standard Time,
philliplc(AT)CHARTER.NET writes:
Presumably the total percentage of gulls in the northwest
Atlantic
available to be blown east by storms that also happen to be
Glaucous-winged is pretty small : ) If this bird showed up in
the
company of dozens of smithsonianus that might make more sense.
=09
If the bird in question is a G-w from normal range, some sort of
reverse
migration over the polar regions might be a shorter path,
particularly
for one originating in Siberia. Don't have a globe handy lol.
Hi Phil
=20
White-winged gulls generally arrive in large numbers in Britain and
Ireland in late January/February, following gale-force Northwesterly
winds. This winter we have not had such conditions and as a result a
paucity of both Glaucous and Iceland Gulls. However, in mid December, we
had an almost unprecedented system arrive in from the Mid Atlantic and
this produced record numbers of Leach's Petrels and somewhat
surprisingly, single first-winter Ivory and Ross's Gulls. I am presuming
the GWG arrived under the same conditions.=20
=20
Lee G R Evans
British Birding Association
UK400 Club, Rare Birds Magazine, Ornithological Consultant and
Conservationist
Discussion Forum/Email Group: http://groups.yahoo.com/group/UK400Club/
Email Address: LGREUK400(AT)aol.com
Website Address: www.uk400clubonline.co.uk
<http://www.uk400clubonline.co.uk/>=20
8 Sandycroft Road
Little Chalfont
Amersham
Buckinghamshire
England
HP6 6QL
Telephones: 01494 763010 and 01494 581157
Mobile/Text Alerts: 07881 906629
(Lee Evans Enterprises incorporate documentation of rare bird
occurrences in Britain & Ireland and elsewhere in the Western Palearctic
and in North America; Rare Bird Information and Rare Bird Alerts; Rare
Birds Magazine and other related publications; Bird Tours for Birders;
also Mobile Discos (Nighthawk Roadshow); CD Vinyl & DVD Sales; Haynes
Car Manuals For Sale; Prestige Car Delivery; UK Courier and Road Traffic
Officing)
Join or Leave BIRDWG01:
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Subject: Causes of extreme vagrancy
From: "Wayne C. Weber" <contopus(AT)TELUS.NET>
Date: 5 Jan 2007 12:44pm
Bird ID People,
I'm afraid that I must differ with Norman van Swelm when he states
that "Extreme vagrancy is caused by extreme atmospheric conditions".
In a large percentage of cases-- perhaps even the majority of
cases-- this statement may be true to some degree. Many records
of long-distance vagrants are associated with, and presumably
caused by, unusual weather conditions such as hurricanes or
other severe storms, unusual wind patterns, etc.
However, at least two other factors could be responsible for
long-distance vagrancy:
(1) A genetic abnormality in the vagrant individual (assuming that
there is a genetic component to migration patterns.) For all we know,
this could result from something as simple as a single-gene mutation,
as well as from a hybrid origin for the vagrant.
The theory of mirror-image misorientation, put forward by Dave DeSante
et al., could account for a large percentage of sightings of eastern
North American species that show up in California and elsewhere
in the West. Many of these birds show up under perfectly normal
weather conditions, although it is also true that numbers of "eastern"
vagrant landbirds have been much higher in some years with
unusual wind patterns.
It seems likely that mirror-image misorientation has a genetic basis,
although this is unproved and probably unprovable at our current
state of knowledge of the inheritance of migratory tendencies.
(2) Many long-distance vagrants could simply be individuals that
show unusual behavior, without any genetic abnormalities or
predisposing weather conditions.
The contribution of unusual weather to vagrancy also varies
greatly from species to species. In some species (e.g. inland records
of Ancient Murrelets in North America), nearly all vagrant records
seem to be linked to unusual weather (i.e., storms). In other
species (e.g. extralimital records of Rock Wrens and Northern
Mockingbirds), there appears to be little or no relation to unusual
weather, and even seasonal patterns can be hard to discern.
At any rate, I believe that it is quite inaccurate to attribute all
long-distance vagrancy to unusual weather conditions.
Wayne C. Weber
Delta, BC, Canada
contopus(AT)telus.net
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Subject: FW: Glaucous-winged age
From: "Lethaby, Nick" <nlethaby(AT)TI.COM>
Date: 5 Jan 2007 2:00pm
This is a multi-part message in MIME format.
----INCLUDING text/plain MIME SECTION----
All:
=20
As pointed out below my mail should have said EAST of the rockies.
=20
Nick Lethaby
DSP/BIOS Product Manager
Software Development Systems
Texas Instruments
805 562 5106
nlethaby(AT)ti.com
=20
________________________________
From: Smith, Michael [mailto:Michael.Smith(AT)maine.gov]=20
Sent: Friday, January 05, 2007 11:30 AM
To: Lethaby, Nick
Subject: RE: [BIRDWG01] Glaucous-winged age
=20
presumably you meant EAST of the Rockies they are rare...
=20
*********
Michael Smith
Maine DEP=20
=20
=20
________________________________
From: NBHC ID-FRONTIERS Frontiers of Field Identification
[mailto:BIRDWG01(AT)LISTSERV.ARIZONA.EDU] On Behalf Of Lethaby, Nick
Sent: Friday, January 05, 2007 2:28 PM
To: BIRDWG01(AT)LISTSERV.ARIZONA.EDU
Subject: Re: [BIRDWG01] Glaucous-winged age
All:
=20
I think the presumption that the GWGU arrived across the Atlantic is not
necessarily correct. It could have come through Arctic Russia. While
this isn't necessarily a likely route either, GWGUs are extremely rare
W. of the Rockies in the USA, rarer than species like California Gull or
even Slaty-backed Gull, neither of which has appeared in Europe to my
(limited) knowledge.
=20
Nick Lethaby
DSP/BIOS Product Manager
Software Development Systems
Texas Instruments
805 562 5106
nlethaby(AT)ti.com
=20
________________________________
From: NBHC ID-FRONTIERS Frontiers of Field Identification
[mailto:BIRDWG01(AT)LISTSERV.ARIZONA.EDU] On Behalf Of Lee Evans
Sent: Friday, January 05, 2007 11:16 AM
To: BIRDWG01(AT)LISTSERV.ARIZONA.EDU
Subject: Re: [BIRDWG01] Glaucous-winged age
=20
In a message dated 05/01/2007 18:05:44 GMT Standard Time,
philliplc(AT)CHARTER.NET writes:
Presumably the total percentage of gulls in the northwest
Atlantic
available to be blown east by storms that also happen to be
Glaucous-winged is pretty small : ) If this bird showed up in
the
company of dozens of smithsonianus that might make more sense.
=09
If the bird in question is a G-w from normal range, some sort of
reverse
migration over the polar regions might be a shorter path,
particularly
for one originating in Siberia. Don't have a globe handy lol.
Hi Phil
=20
White-winged gulls generally arrive in large numbers in Britain and
Ireland in late January/February, following gale-force Northwesterly
winds. This winter we have not had such conditions and as a result a
paucity of both Glaucous and Iceland Gulls. However, in mid December, we
had an almost unprecedented system arrive in from the Mid Atlantic and
this produced record numbers of Leach's Petrels and somewhat
surprisingly, single first-winter Ivory and Ross's Gulls. I am presuming
the GWG arrived under the same conditions.=20
=20
Lee G R Evans
British Birding Association
UK400 Club, Rare Birds Magazine, Ornithological Consultant and
Conservationist
Discussion Forum/Email Group: http://groups.yahoo.com/group/UK400Club/
Email Address: LGREUK400(AT)aol.com
Website Address: www.uk400clubonline.co.uk
<http://www.uk400clubonline.co.uk/>=20
8 Sandycroft Road
Little Chalfont
Amersham
Buckinghamshire
England
HP6 6QL
Telephones: 01494 763010 and 01494 581157
Mobile/Text Alerts: 07881 906629
(Lee Evans Enterprises incorporate documentation of rare bird
occurrences in Britain & Ireland and elsewhere in the Western Palearctic
and in North America; Rare Bird Information and Rare Bird Alerts; Rare
Birds Magazine and other related publications; Bird Tours for Birders;
also Mobile Discos (Nighthawk Roadshow); CD Vinyl & DVD Sales; Haynes
Car Manuals For Sale; Prestige Car Delivery; UK Courier and Road Traffic
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Subject: Re: Glaucous-winged age
From: Alvaro Jaramillo <chucao(AT)COASTSIDE.NET>
Date: 5 Jan 2007 4:17pm
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Lee
I said it was a second cycle bird, Phil said is was a third, and I
thought and noted later that he's probably right. Then I started looking
through my photos, which I posted, and confirmed my general impression that
ageing some of these birds is an exercise in circular logic. The problem is
that here, unlike in Europe where you have lots of color banding schemes, is
that we have no known age Glaucous-wings to test any of this age stuff with,
so really they are logical guesses. Based on the small sample of known age
Western Gulls I have photographed (not all of them on my site), on the whole
the Gloucester bird better fits a third cycle bird but not cleanly. So I
would put my vote as a third cycle bird, and note that it would be great to
see a photo of spread wing showing the secondaries and inner primaries.
The hybrid combinations that you mention do not (again good guesses) fit
what we identify as being those combinations. If this bird is a hybrid, I
would suggest that it has to have Western Gull genes in it.
To give a perspective on the hybrid issue, there is a large zone in the
Pacific Northwest where there is a hybrid swarm between Western and
Glaucous-winged Gulls. These are not one off hybrids, but en entire
population of many, many, many thousands of birds with mixed genes. The
adults at the breeding colonies have been studied, but we have no color
banding schemes to tell us exactly which birds we are seeing throughout a
large portion of the Pacific Coast are from the hybrid zone. So we make
assumptions and identify some as pure Western some as pure Glaucous-winged,
and some as hybrids (sometimes hundreds of hybrids in a day's birding!!) So
the problem then is that we have no idea how variable pure populations of
immature Glaucous-winged Gulls are, Japan may be a good model, but then
again their birds may not look exactly like ours. I have no issue calling
that bird a Glaucous-winged Gull, on the dark side, but it is not a classic
bird.
Local Car parks and gulls: I am not as lucky as the British Columbia to
Oregon birders who get Glaucous-wings on the street, I have to go to the
beach to see them. In fact I may go down there in a few minutes just to take
a few more shots. There are all sorts of different looking Glaucous-wings
down there, and surely all of the features shown by this bird can be matched
by birds at my local beach. The issue is that I still can't tell you if all
of those, particularly the darker ones, are pure Glaucous-wings or not, they
may not be obvious hybrids, but maybe they are from the hybrid zone? So if
there are 10 birds at a car park that look like this in Oregon, what does it
do for the identification of the Gloucester bird? I am actually not being
the devil's advocate here, I may be voicing my frustration at so many gulls
over the years which go unnamed around here, or named even though we should
have left them unnamed. I love them and hate them for the same reason. In
the end this will come down to whether the rarities committee is comfortable
with the identification or not, and comfortable with the intrinsic
uncertainty that there is in identifying any Glaucous-winged Gull that is
not classic. Maybe it has some mixed genes, maybe it is perfectly within
normal variation, but on the whole I would vote for that bird as a
Glaucous-winged Gull.
Anybody have some $$ who wants to fund a long term color banding scheme here
on the West Coast?
Cheers
Alvaro
Alvaro Jaramillo
chucao(AT)coastside.net
Half Moon Bay, California
Field Guides - Birding Tours Worldwide
www.fieldguides.com
_____
From: NBHC ID-FRONTIERS Frontiers of Field Identification
[mailto:BIRDWG01(AT)LISTSERV.ARIZONA.EDU] On Behalf Of Lee Evans
Sent: Friday, January 05, 2007 9:44 AM
To: BIRDWG01(AT)LISTSERV.ARIZONA.EDU
Subject: Re: [BIRDWG01] Glaucous-winged age
Alvaro
I am no expert in North American gull ageing but my concern over the
Gloucester bird (currently being touted as a 2nd-winter) is that there is a
white mirror on p10 (primary 10). In my opinion, this leans heavily towards
the bird being a retarded 3rd-winter but I would very much welcome comments
from anyone that spends time studying and photographing them. I am also in
the process of documenting this record and would very much appreciate any
good images of first, second, third and fourth winter birds from North
America.
Furthermore, I was concerned that the Gloucester bird may well be a hybrid,
perhaps North American Herring x Glaucous Gull or North American Herring
Gull x Glaucous-winged Gull, but I hear that Steve Howell and others are
happy that the bird is a 'pure' GWG.
All the very best and many thanks for taking time to comment on this bird
Lee G R Evans
British Birding Association
UK400 Club, Rare Birds Magazine, Ornithological Consultant and
Conservationist
Discussion Forum/Email Group: http://groups.yahoo.com/group/UK400Club/
Email Address: LGREUK400(AT)aol.com
Website Address: www.uk400clubonline.co.uk
<http://www.uk400clubonline.co.uk/>
8 Sandycroft Road
Little Chalfont
Amersham
Buckinghamshire
England
HP6 6QL
Telephones: 01494 763010 and 01494 581157
Mobile/Text Alerts: 07881 906629
(Lee Evans Enterprises incorporate documentation of rare bird occurrences in
Britain & Ireland and elsewhere in the Western Palearctic and in North
America; Rare Bird Information and Rare Bird Alerts; Rare Birds Magazine and
other related publications; Bird Tours for Birders; also Mobile Discos
(Nighthawk Roadshow); CD Vinyl & DVD Sales; Haynes Car Manuals For Sale;
Prestige Car Delivery; UK Courier and Road Traffic Officing)
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Subject: 3rd-year Glaucous-wings
From: Alan Contreras <acontrer(AT)MINDSPRING.COM>
Date: 5 Jan 2007 7:58pm
I read the section on Glaucous-wings in Dwight (1925) this evening to see if
that older but very detailed reference could shed any light on the Gull from
Heck in the UK.
Dwight treats the second-winter G-wing as reasonably straightforward with
"drab" primaries "rarely with a suggestion of a mirror" on the outer
primary, and the third-winter as extremely variable, usually showing spots
but sometimes completely lacking apical spots. He uses the term "backward
birds" to refer to these more patchy third-winters that have retained
certain second-winter characteristics.
One small factlike nugget to add to the discussion. Thus I now lean to Phil
Pickering's view that this is a third-winter bird.
--
Alan Contreras
EUGENE, OREGON
acontrer(AT)mindspring.com
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Subject: Re: Blackpoll vs Bay-breasted (long)
From: David Seibel <dseibel(AT)JCCC.EDU>
Date: 5 Jan 2007 8:05pm
This is a multi-part message in MIME format.
----INCLUDING text/plain MIME SECTION----
Thanks to everyone who commented on my "Baypoll" warbler a couple of =
weeks ago (Dec. 13-19). Sorry for my slow reply; I've been in the field =
for a while and am just now getting back to my e-mail. I'd like to =
address a few questions about my photos =
(http://staff.jccc.edu/dseibel/birds/BLPW.htm ) and try to extract some =
conclusions from the recent discussion and my own thoughts.=20
=20
Several people wondered about the accuracy of color and contrast in the =
images. This is obviously subject to variation with different monitors, =
but there are also apparent color shifts among some of the images in the =
series. I believe these are mostly caused by changes in ambient light =
as the bird moved among different branches and trees, with one =
exception. Beginning with the 9th image, I switched my flash from -2/3 =
to -1 1/3 exposure compensation. This probably accounts for the sudden =
increase in greenish tones in the bird's body feathers and the darker, =
grayer background. Since I was using auto white balance, the colors are =
probably more accurate on the first 8 images.
=20
I took the whole series of photos between 9:35:18 and 9:37:13 AM (CDT) =
on Sept. 5 in northeastern Kansas, and so the sun was high enough for =
harsh light to penetrate gaps in the canopy. (The bird was only in =
sight for these two minutes.) The habitat was remnant eastern deciduous =
forest. The bird was foraging silently at the edge of a sunlit clearing =
on the west side of a gravel road, where I set up my tripod. I kept the =
sun to my back or side for all of the photos, and I used an external =
E-TTL flash with fresnel lens, adjusted for underexposure as described =
above, for subtle fill. Flash effects on contrast and saturation should =
be minimal, especially from the 9th image to the end, again with one =
important exception: relatively glossy surfaces (such as the eye, bill, =
and underside of the rectrices) sometimes reflect even low levels of =
flash enough to produce a glare. I think some of the confusing =
appearance of the tail spots can be explained by this. For my web page, =
I processed the RAW images (original size 3504 x 2336 pixels) in =
BreezeBrowser Pro with a consistent, minimal color-correction algorithm =
(auto levels, black point 0.05%, white point 0.05%), and all are full =
frame except for the final detail of the tail, which is a 100% crop. I =
calibrate my monitor with a Gretag MacBeth system for color accuracy.
=20
Some additional points and my comments (preceded by -----) follow.
=20
Tom Schultz wrote:
"[Characteristics consistent with Bay-breasted include] hints of buffy =
coloration in flanks, upper breast, and base of undertail coverts. A =
Blackpoll would generally show more of a pure lemony yellow in the =
underparts -- especially the neck sides and upper breast."
----- I always have trouble figuring out exactly what "buffy" means, =
especially in combination with other colors. In the original images, =
the yellow is never "pure lemony," but neither is there any of the =
peachy tint that often occurs in Bay-breasted.
"... fall Blackpolls have bi-colored bills that have some yellowish =
along the cutting edge and at the base of the lower mandible. =
Bay-breasteds are also bi-colored but typically have pinkish or =
flesh-colored tints in these areas. This bird appears to match the =
latter pattern."
----- There is indeed no hint of yellow on the bill in any of the =
images. The tomia and base of the lower mandible appear to have a pale =
pinkish gray or fleshy horn-colored tint, depending on the light.
"... a small percentage of Bay-breasteds can have dusky streaking or =
'stippling' on the breast sides."
----- The streaks appear to be jet black on the KS bird, but this is =
close enough to weaken one of my main arguments against Bay-breasted.
=20
Allen Chartier wrote:
"... most of the photos show tail spots quite unlike what I'm used to =
seeing in either Bay-breasted or Blackpoll, but appear more like those =
on Chestnut-sided or Black-throated Green. However, that 19th image =
again (and the final close-up image) makes the spot on r6 look different =
from the other photos, and would be similar the extreme (large) end of =
the scale for an adult male Blackpoll or Bay-breasted."
----- Backlighting, shadow, and flash glare seem to have a big impact on =
the appearance of the tail spots. The 19th image actually shows =
stronger glare than most, but the dark bases of the outer rectrices =
happen to be accentuated by shadow. Of the posted images, the only one =
I would trust for the tail pattern is the last one, showing the details =
at 100%. It is consistent with the appearance of the other images at =
full size. By the way, the bar across the right outer rectrix is really =
there (it's visible in several images).
=20
Matt Sharp wrote:
"Interestingly the wing edging is brightest yellow ... on the second to =
last pic in the series ... which is the only pic which shows any yellow =
tones on the legs (in that pic it is on the back of the tarsi)."
----- In the original image, the yellowish cast on the wing appears to =
be intensified by reflection from the leaves above the bird. It had =
just flown to a different tree, and the lighting changed accordingly. =
There is actually no hint of yellow on the tarsi, although the back =
edges are distinctly paler gray, as are the toe pads. This is =
consistent in all the original images.
=20
Dave Rintoul wrote:
"From a purely statistical point of view, Bay-Breasted is much more =
likely in eastern Kansas on Sept 5."
----- Agreed, although obviously not a conclusive factor in the =
identification.
=20
David Sibley wrote:
"... how much of my first impressions of the odd appearance of this bird =
is due to high contrast in the photos? Some photos show a white throat, =
while others show yellowish. Some photos show a strange blotchy pattern =
of yellowish and white on the breast. It seems possible that even the =
appearance of bright white undertail coverts could be caused by =
increased contrast and the camera "reading" pale yellowish as white."
----- The blotchy pattern is probably the result of dappled light and =
shadow from overlying leaves. Except for images 1, 17, and 18, there =
are no "blown" highlights in the bird's underparts, and the spots of =
excessive contrast are obvious in those. Otherwise, the relative tones =
and contrast should be accurate.
"Some field description would be very helpful for confirming the =
appearance of the photos, especially whether or not the undertail =
coverts appeared white in the field."
----- The undertail coverts looked pure white in the field, and the =
contrasting pale edges of the greater secondary coverts were clearly =
visible as well. (These two characters, plus the black streaks on the =
sides of the breast, are why I initially thought it was a Blackpoll.) I =
couldn't see the hints of yellow in the undertail coverts until I viewed =
the images on my monitor.
"Someone with access to a collection could quickly check tail patterns =
and greater covert edges and report on how obvious and how variable =
these features are on fall Bay-breasted."
----- A collection with a big enough series of fall Blackpolls and =
Bay-breasteds, of course! (How big would this be?) This is on my list =
of things to do, but I'd be glad to hear from anyone who beats me to it.
"... I don't recall ever seeing a Blackpoll or Bay-breasted warbler with =
the white tail spots meeting the pale undertail coverts and showing no =
dark at the base of the outer tail feathers."
----- The outer rectrix of the KS bird actually has a dark base =
(although not as dark as the tip), with only a thin pale strip along the =
medial margin extending to the undertail coverts =
(http://staff.jccc.edu/dseibel/birds/BLPW.htm#tail). I believe glare =
and/or backlighting makes the dark base less prominent in most of the =
photos, especially at their reduced size. For comparison, here's an =
image of a Bay-breasted in the hand, showing a tail pattern with an even =
smaller (though darker) dark base: =
http://mobirds.org/MysteryBird/MB3.asp?type=3DAnswer. (On my monitor, =
the image is distorted in the web page, but it looks much better if you =
save the image and open it separately.) Note that this bird also has =
very pale undertail coverts, even taking into account the blown =
highlights! I need to track down the details of where and when these =
photos were taken.
=20
Richard Heil wrote:
"I still contend that photos #17-19 appears to show pale yellowish (or =
at least contrastingly paler, whatever the color) undersides to the =
feet."
----- They are indeed contrastingly paler (gray), but there is no hint =
of yellow in the originals.
"... some birds from Alaska may have ... more olive upperparts. Pyle =
says birds breeding west of Ontario may average slightly larger and =
duller.... Probably a Blackpoll in Kansas would be more likely an =
Alaskan (or western) product than being one originating from say =
Quebec."
----- Very possible, especially in the fall. I believe there are more =
fall Blackpoll records in Colorado and western Kansas than in eastern =
Kansas.
=20
Julian Hough wrote:
"... the olive fringed greater coverts referred to by several people =
seem fine for either species in my opinion..."
----- I learned this character from Sibley (2000). In my limited =
experience since then, fall Bay-breasteds tend to have narrower pale =
fringes or none, giving their coverts a more uniform appearance, while =
Blackpolls' coverts have a more striped appearance.
=20
Christopher Vogel wrote:
"... one strike against it being an indistinctly marked Blackpoll is the =
fact that it has dark legs. If it has dark legs, melanin being as it is, =
it should follow that it would be overall a heavily marked, not toned =
down or yellowish Blackpoll."
----- The legs might not be abnormally dark, but simply lacking yellow. =
The areas that would normally be yellow in a Blackpoll are distinctly =
paler gray in the KS bird. (But is this any different from the normal =
condition of a Bay-breasted?)
=20
Allen Chartier wrote:
"I've been wondering if there are any additional photos of this bird, =
which might show an open wing.... to see whether p6 is emarginated or =
not; yet another (frequent) distinction between Bay-breasted and =
Blackpoll."
----- No, I'm afraid I posted everything I captured. I inspected all of =
the full-sized images but couldn't make out the edge of p6 clearly =
enough to be of any help.
=20
Conclusions: (1) I need to examine specimens, probably lots of them, =
and preferably with detailed notes on soft part colors. (2) I still =
don't know whether anyone has ever documented a Blackpoll with no yellow =
on its tarsi or toes. If not, it seems unlikely that the KS bird was a =
Blackpoll. At any rate, the normal condition certainly points toward =
Bay-breasted. (3) One of my primary arguments against Bay-breasted, the =
black breast streaks, is apparently within the range of variation for =
that species (fide Tom Schultz). (4) The hint of yellow in the =
undertail coverts may be significant. In the original images, several =
feathers have a very faint yellowish (not buffy) wash. The presence of =
any color may be yet another point in favor of Bay-breasted, as =
suggested by the photos I referenced above =
(http://mobirds.org/MysteryBird/MB3.asp?type=3DAnswer). (5) I need to =
examine the reliability of the contrasting pale edges of the greater =
secondary coverts as a Blackpoll character. If the preceding points =
withstand scrutiny, this could prove to be the last significant barrier =
to calling the KS bird a Bay-breasted. (I'm not ignoring Chistopher =
Vogel's bill thickness argument or other points in favor of Blackpoll. =
They just strike me as less compelling than the combination of =
characters that indicate Bay-breasted - IF the characters listed here =
all prove to be at least neutral.) (6) If points # 3, 4, and 5 fail to =
support Bay-breasted, and I can't find any other reference to a =
gray-footed Blackpoll, I'll return to the hybrid Blackpoll x =
Bay-breasted hypothesis. And probably admit defeat. (7) Sometimes a =
bird in the hand is definitely worth 2 (or more) in digital form!
=20
Thanks again to everyone who has contributed. More ideas always =
welcome.
=20
David Seibel
Lenexa, Kansas USA
=20
=20
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Subject: Re: seeking feedback on two more gulls -
clarification and more
From: Martin Reid <upupa(AT)AIRMAIL.NET>
Date: 5 Jan 2007 9:10pm
Dear all,
Lariphobes hit the delete key.
I've enjoyed the GWGU discussion, and learned a lot - thanks to all.
I have received a number of replies about the two birds recently
posted (165, 166) but it seems I have confused some on the page for
gullsp165 - the first-cycle bird here:
http://www.martinreid.com/Gull%20website/gullsp166.html
- if you refresh the page you'll see a clarification paragraph
confirming that all the photos pertain to the same individual gull.
Regarding the Utah small gull, I was disappointed to see that there
were no further responses after my post in which I provided URLs for
birds that looked in varying degrees like the Utah bird, all from the
expected range of kumlieni. This kind of leaves me (and others?) up
in the air, since there were so many people previously saying that a
bird like this (Utah bird) should not be called a kumlieni - ?
Anyway, to add to the mix, here is a bird I found yesterday in
Texas; it's a slightly different type of kumlieni wannabe - what do
you think?:
http://www.martinreid.com/Gull%20website/gullsp166.html
And for those with no life, I offer two more intriguing gulls:
http://www.martinreid.com/Gull%20website/gullsp167.html
(freaky LBBG? Kelp? weird hybrid?)
http://www.martinreid.com/Gull%20website/gullsp168.html
(freaky LBBG? Azorean YLGU?)
Cheers,
Martin
--
>Martin Reid
>San Antonio, Texas
>mailto:upupa(AT)airmail.net
>http://www.martinreid.com
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Subject: Interesting gull in Michigan
From: Allen Chartier <amazilia1(AT)COMCAST.NET>
Date: 6 Jan 2007 7:59am
Birders,
Not being much of a gull person, I'm a bit hesitant to post this as I'll
only be able to answer questions about what this bird looked like, and not
participate in any further discussions. An interesting gull has been found
at the Salem Twp. landfill, Washtenaw Co., Michigan, and has initially been
labeled a probable Yellow-legged Gull, but in reviewing many internet
photos, it would appear perhaps indistinguishable from hybrids between
Herring and Lesser Black-backed. It would also appear that there is complete
overlap in all characters between pure YLGU and hybrid LBBGxHERG. All of the
photos of hybrids we've found are from Europe, involving argenteus HERG, so
we don't really know what a LBBG cross with a smithsonianus HERG would look
like. How are pure YLGU identified with certainty in Newfoundland? Only the
individuals with screaming yellow legs?
A few photos (no spread wing shots are available - whatever that would tell
us) are posted at:
> http://www.umich.edu/~bbowman/birds/se_mich/photos.html
Allen Chartier
amazilia1(AT)comcast.net
1442 West River Park Drive
Inkster, MI 48141
Website: http://www.amazilia.net
Michigan HummerNet: http://www.amazilia.net/MIHummerNet
===============================================
Every day, the hummingbird eats its own weight in food.
You may wonder how it weighs the food. It doesn't.
It just eats another hummingbird.
---Steven Wright
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Subject: Re: Interesting gull in Michigan
From: Dick Newell <dick.newell(AT)ZEN.CO.UK>
Date: 6 Jan 2007 9:36am
[I tried posting this privately to Allen, but it bounced].
Re: http://www.umich.edu/~bbowman/birds/se_mich/photos.html
Being the least qualified to comment, but knowing European YLG fairly well
and with an acquaintance with atlantis, I'll have a go. This is not a YLG of
any sort (I am ignoring the fact that the legs look pink on my screen).
Given that American HERG varies from Kodak 3 to 6 (3 = ~Ring-billed, 6 = ~
Common Gull), then seeing 2 contrasting American HERG's together in winter
is not that surprising. If the legs have a yellowish tinge, one explanation
could be diet.
Dick
Cambridge, UK
On 6/1/07 14:59, "Allen Chartier" <amazilia1(AT)COMCAST.NET> wrote:
> Birders,
>
> Not being much of a gull person, I'm a bit hesitant to post this as I'll
> only be able to answer questions about what this bird looked like, and not
> participate in any further discussions. An interesting gull has been found
> at the Salem Twp. landfill, Washtenaw Co., Michigan, and has initially been
> labeled a probable Yellow-legged Gull, but in reviewing many internet
> photos, it would appear perhaps indistinguishable from hybrids between
> Herring and Lesser Black-backed. It would also appear that there is complete
> overlap in all characters between pure YLGU and hybrid LBBGxHERG. All of the
> photos of hybrids we've found are from Europe, involving argenteus HERG, so
> we don't really know what a LBBG cross with a smithsonianus HERG would look
> like. How are pure YLGU identified with certainty in Newfoundland? Only the
> individuals with screaming yellow legs?
>
> A few photos (no spread wing shots are available - whatever that would tell
> us) are posted at:
>
>> http://www.umich.edu/~bbowman/birds/se_mich/photos.html
>
> Allen Chartier
> amazilia1(AT)comcast.net
> 1442 West River Park Drive
> Inkster, MI 48141
> Website: http://www.amazilia.net
> Michigan HummerNet: http://www.amazilia.net/MIHummerNet
> ===============================================
> Every day, the hummingbird eats its own weight in food.
> You may wonder how it weighs the food. It doesn't.
> It just eats another hummingbird.
> ---Steven Wright
>
>
> Join or Leave BIRDWG01:
http://listserv.arizona.edu/cgi-bin/wa?SUBED1=birdwg01
>
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Subject: Re: Interesting gull in Michigan
From: Ottavio Janni <coeligena(AT)HOTMAIL.COM>
Date: 6 Jan 2007 9:48am
----INCLUDING text/plain MIME SECTION----
=20
Hi Allen and all,
=20
I looked at the photos of the gull from Michigan and my impression is that =
it is not a Yellow-legged Gull, at least not of the nominate subspecies. St=
ructurally the head seems too evenly rounded, the legs rather short, and it=
does not look particularly long in the rear. I think the pattern of head s=
treaking is a major problem for nominate YLGU. By early January, at least h=
ere in Italy, most adult YLGU have immaculate white heads, with a minority =
showing a little bit of streaking around the eye, but never as much as on t=
he Michigan bird. Even allowing for a different molt schedule for a vagrant=
, the pattern itself seems wrong for nominate YLGU, on which streaking is a=
lways rather limited (even in Aug-Oct when it is most evident) and concentr=
ated around the eye and on the crown. The necklace of streaks on the hindne=
ck is something I basically never see on adult YLGU. Leg color is also a pr=
oblem, I think it is a bit variable but on adults yellow tones seem to alwa=
ys be predominant, which I'm not really seeing on the Michigan bird, at lea=
st not to the extent that I would expect on YLGU. Although for a vagrant th=
is is probably a moot point, by early January most adult YLGU here are alre=
ady thinking about breeding, and their soft part colors are at their bright=
est between now and early spring. I'm not really sure to what extent my com=
ments apply to atlantis YLGU, but I would guess that structure and soft par=
t colors are wrong for that subspecies as well? Also, has argentatus Herrin=
g Gull been considered as a possibility?
=20
Hope this helps,
=20
Ottavio Janni
Italy
_________________________________________________________________
Type your favorite song.=A0 Get a customized station.=A0 Try MSN Radio powe=
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Subject: Re: Interesting gull in Michigan
From: Bruce Mactavish <bruce.mactavish1(AT)NF.SYMPATICO.CA>
Date: 6 Jan 2007 1:13pm
Interesting gull. Resembles a number of birds we call Lesser
Black-backed Gull x Herring Gull in Newfoundland. Knowing orbital ring
colour and especially wing tip pattern would say a lot.
The legs do not look yellow enough even considering the photos are all
on the under exposed side. The head streaking, which should be gone even
on the later moulting races (e.g. Azorean) of Yellow-legged Gull in
early January, rarely extends onto the neck on any population of
Yellow-legged Gull.
The upperparts colour looks fine for YLGU. The relatively thick
brightly coloured bill with red of gony bleeding to upper mandible is
good for YLGU. It can occur and is not that rare in smithsonianus
Herring Gulls. Although head shape is highly variable among individual
gulls depending on mood and posture, this bird looks relaxed, the domed
head shape doesn't feel right for YLGU. The head shape in combination
with less than full chested look typical of YLGUs gives this a Herring
Gull shape overall.
Head streaking on smithsonianus and LBBG is typically heavier than this
but I see many examples of both species with similar head streaking
during the peak period of head streaking December and January.
I'd throw this in the bin labelled 'Suspect Lesser Black-backed Gull X
Herring Gull'.
Bruce
Bruce Mactavish
St. John's, Newfoundland
Canada
bruce.mactavish1(AT)nf.sympatico.ca
-----Original Message-----
From: NBHC ID-FRONTIERS Frontiers of Field Identification
[mailto:BIRDWG01(AT)LISTSERV.ARIZONA.EDU] On Behalf Of Allen Chartier
Sent: Saturday, January 06, 2007 11:30 AM
To: BIRDWG01(AT)LISTSERV.ARIZONA.EDU
Subject: [BIRDWG01] Interesting gull in Michigan
Birders,
Not being much of a gull person, I'm a bit hesitant to post this as I'll
only be able to answer questions about what this bird looked like, and
not
participate in any further discussions. An interesting gull has been
found
at the Salem Twp. landfill, Washtenaw Co., Michigan, and has initially
been
labeled a probable Yellow-legged Gull, but in reviewing many internet
photos, it would appear perhaps indistinguishable from hybrids between
Herring and Lesser Black-backed. It would also appear that there is
complete
overlap in all characters between pure YLGU and hybrid LBBGxHERG. All of
the
photos of hybrids we've found are from Europe, involving argenteus HERG,
so
we don't really know what a LBBG cross with a smithsonianus HERG would
look
like. How are pure YLGU identified with certainty in Newfoundland? Only
the
individuals with screaming yellow legs?
A few photos (no spread wing shots are available - whatever that would
tell
us) are posted at:
> http://www.umich.edu/~bbowman/birds/se_mich/photos.html
Allen Chartier
amazilia1(AT)comcast.net
1442 West River Park Drive
Inkster, MI 48141
Website: http://www.amazilia.net
Michigan HummerNet: http://www.amazilia.net/MIHummerNet
===============================================
Every day, the hummingbird eats its own weight in food.
You may wonder how it weighs the food. It doesn't.
It just eats another hummingbird.
---Steven Wright
Join or Leave BIRDWG01:
http://listserv.arizona.edu/cgi-bin/wa?SUBED1=birdwg01
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[ << | >> | ^^ ]
Subject: Re: "Glaucous-winged" Gull in Gloucestershire
From: Martin Reid <upupa(AT)AIRMAIL.NET>
Date: 6 Jan 2007 2:11pm
Dear All,
Firstly here's the Dutch bird that I presume Norman is referring to:
http://www.martinreid.com/Gull%20website/gullsp06.html
- I am not sure why Norman feels this may be a GWGU; I wouldn't.
Secondly Phil said he'd liked to have seen some horizontal barring on
the upper chest, as a feel-good factor. Well, if you look closely at
the head shot of the captured bird, you can see a few horizontal
marks, plus I downloaded, zoomed-in and sharpened slightly on the
standing bird image, and feel I can see some faint horizontal barring
on the chest. Anyone else see this?
Lastly, I am one of those who thinks that some vagrants are so due to
a genetic abnormality (partly at least) , and that the abnormality
could be affecting more than its migration blueprint - i.e.
morphology. If I recall rightly, the UK's only Varied Thrush was one
of those rare (1 in 500? 1 in 1000? - anyone?) forms that is white
where the orange would normally be found. This proved no obstacle to
it being accepted onto the British List (correct me if I'm wrong).
Cheers,
Martin
--
>Martin Reid
>San Antonio, Texas
>mailto:upupa(AT)airmail.net
>http://www.martinreid.com
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Subject: Re: Interesting gull in Michigan
From: Allen Chartier <amazilia1(AT)COMCAST.NET>
Date: 6 Jan 2007 2:53pm
Bruce,
Most of these photos were taken in very overcast, dim conditions, at mainly
1/15 to 1/30 second. A few were tried at 1/60 and 1/125 second but made the
bird's mantle look almost like a Great Black-backed! They were digiscoped
with a Nikon Coolpix 995 through a Kowa TSN3 at effective magnifications
ranging from 80-240x. The landfill was very muddy, and the bird's legs were
definitely a bit dirty, which may have a minor effect on the appearance of
their color. I have a total of 23 "good" images (out of ~100 taken) that I
can e-mail directly to anyone who is interested.
The orbital ring was very definitely reddish-pink, and is visible on my
monitor on the one photo of the head and shoulders that I posted. This may
not show up on all monitors, I guess. There was a HUGE white mirror on p10,
and a suggestion of its extent can be seen on the underside of the far wing
in the one photo showing the rear of the bird. We have no photos of the
bird's spread wing.
The impression of this bird's body shape, compared with the many Herring
Gulls present, was of a slightly more elongated, chestier bird with a
flatter belly. The angles in the photos may not portray this well. In
flight, the bird appeared larger than most of the Herring Gulls (longer or
broader wings?) with a very wide white trailing edge, but at rest it
appeared similar in size or slightly smaller than nearby Herring Gulls.
It was not relocated today. The landfill was only open until noon today, and
is closed tomorrow. Hopefully, the bird can be relocated, and perhaps better
sky conditions will prevail, though in Michigan the skies usually get
overcast on November 1 and don't clear again until April 1...
Having said all this, I'm tending to want to put it in the same bin you've
suggested.
Allen Chartier
amazilia1(AT)comcast.net
1442 West River Park Drive
Inkster, MI 48141
Website: http://www.amazilia.net
Michigan HummerNet: http://www.amazilia.net/MIHummerNet
===============================================
Every day, the hummingbird eats its own weight in food.
You may wonder how it weighs the food. It doesn't.
It just eats another hummingbird.
---Steven Wright
----- Original Message -----
From: "Bruce Mactavish" <bruce.mactavish1(AT)nf.sympatico.ca>
To: "'Allen Chartier'" <amazilia1(AT)COMCAST.NET>;
<BIRDWG01(AT)LISTSERV.ARIZONA.EDU>
Sent: Saturday, January 06, 2007 3:15 PM
Subject: RE: [BIRDWG01] Interesting gull in Michigan
> Interesting gull. Resembles a number of birds we call Lesser
> Black-backed Gull x Herring Gull in Newfoundland. Knowing orbital ring
> colour and especially wing tip pattern would say a lot.
>
> The legs do not look yellow enough even considering the photos are all
> on the under exposed side. The head streaking, which should be gone even
> on the later moulting races (e.g. Azorean) of Yellow-legged Gull in
> early January, rarely extends onto the neck on any population of
> Yellow-legged Gull.
>
> The upperparts colour looks fine for YLGU. The relatively thick
> brightly coloured bill with red of gony bleeding to upper mandible is
> good for YLGU. It can occur and is not that rare in smithsonianus
> Herring Gulls. Although head shape is highly variable among individual
> gulls depending on mood and posture, this bird looks relaxed, the domed
> head shape doesn't feel right for YLGU. The head shape in combination
> with less than full chested look typical of YLGUs gives this a Herring
> Gull shape overall.
>
> Head streaking on smithsonianus and LBBG is typically heavier than this
> but I see many examples of both species with similar head streaking
> during the peak period of head streaking December and January.
>
> I'd throw this in the bin labelled 'Suspect Lesser Black-backed Gull X
> Herring Gull'.
>
> Bruce
>
>
>
> Bruce Mactavish
> St. John's, Newfoundland
> Canada
> bruce.mactavish1(AT)nf.sympatico.ca
>
>
> -----Original Message-----
> From: NBHC ID-FRONTIERS Frontiers of Field Identification
> [mailto:BIRDWG01(AT)LISTSERV.ARIZONA.EDU] On Behalf Of Allen Chartier
> Sent: Saturday, January 06, 2007 11:30 AM
> To: BIRDWG01(AT)LISTSERV.ARIZONA.EDU
> Subject: [BIRDWG01] Interesting gull in Michigan
>
> Birders,
>
> Not being much of a gull person, I'm a bit hesitant to post this as I'll
>
> only be able to answer questions about what this bird looked like, and
> not
> participate in any further discussions. An interesting gull has been
> found
> at the Salem Twp. landfill, Washtenaw Co., Michigan, and has initially
> been
> labeled a probable Yellow-legged Gull, but in reviewing many internet
> photos, it would appear perhaps indistinguishable from hybrids between
> Herring and Lesser Black-backed. It would also appear that there is
> complete
> overlap in all characters between pure YLGU and hybrid LBBGxHERG. All of
> the
> photos of hybrids we've found are from Europe, involving argenteus HERG,
> so
> we don't really know what a LBBG cross with a smithsonianus HERG would
> look
> like. How are pure YLGU identified with certainty in Newfoundland? Only
> the
> individuals with screaming yellow legs?
>
> A few photos (no spread wing shots are available - whatever that would
> tell
> us) are posted at:
>
>> http://www.umich.edu/~bbowman/birds/se_mich/photos.html
>
> Allen Chartier
> amazilia1(AT)comcast.net
> 1442 West River Park Drive
> Inkster, MI 48141
> Website: http://www.amazilia.net
> Michigan HummerNet: http://www.amazilia.net/MIHummerNet
> ===============================================
> Every day, the hummingbird eats its own weight in food.
> You may wonder how it weighs the food. It doesn't.
> It just eats another hummingbird.
> ---Steven Wright
>
>
> Join or Leave BIRDWG01:
> http://listserv.arizona.edu/cgi-bin/wa?SUBED1=birdwg01
>
> Archives: http://listserv.arizona.edu/archives/birdwg01.html
>
>
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Subject: Re: Interesting gull in Michigan
From: Robert Wallace <chnuts(AT)YAHOO.COM>
Date: 6 Jan 2007 3:28pm
----INCLUDING text/plain MIME SECTION----
Greetings - last March we found a gull that is very similar to this Michiga=
n bird at the dump in Volusia County (Daytona Beach) FL, on the central Atl=
antic coast. Mantle color was darker than all of the surrounding HEGUs, in=
termediate between them and graellsii LBBGs. Leg color was pale yellow. Th=
ere was some light streaking in the crown, when normally pure YLGUs should =
be pure white. Another interesting feature was the string of pearls on p5-=
8, normally associated with Vega gulls, but which with yellow(ish) legs are=
not discussed anywhere in the literature that I can find, and YLGUs are no=
t described to have this primary pattern either. A hybrid between LBBG and=
HEGU was never considered; is this just a yellow-legged HEGU (but with a d=
arker mantle?), or a YLGU x ? mix.=0A=0ATo help confuse the issue, I have p=
osted photos at the following link:=0A=0Ahttp://www.pbase.com/chnuts/volusi=
a_dump_gull_with_yellow_legs=0A=0AThanks for any comments,=0A=0ABob Wallace=
=0ANew Smyrna Beach FL=0A=0A----- Original Message ----=0AFrom: Bruce Macta=
vish <bruce.mactavish1(AT)NF.SYMPATICO.CA>=0ATo: BIRDWG01(AT)LISTSERV.ARIZONA.EDU=
=0ASent: Saturday, January 6, 2007 3:15:25 PM=0ASubject: Re: [BIRDWG01] Int=
eresting gull in Michigan=0A=0AInteresting gull. Resembles a number of bir=
ds we call Lesser=0ABlack-backed Gull x Herring Gull in Newfoundland. Know=
ing orbital ring=0Acolour and especially wing tip pattern would say a lot.=
=0A=0AThe legs do not look yellow enough even considering the photos are al=
l=0Aon the under exposed side. The head streaking, which should be gone eve=
n=0Aon the later moulting races (e.g. Azorean) of Yellow-legged Gull in=0Ae=
arly January, rarely extends onto the neck on any population of=0AYellow-le=
gged Gull.=0A=0AThe upperparts colour looks fine for YLGU. The relatively =
thick=0Abrightly coloured bill with red of gony bleeding to upper mandible =
is=0Agood for YLGU. It can occur and is not that rare in smithsonianus=0AHe=
rring Gulls. Although head shape is highly variable among individual=0Agul=
ls depending on mood and posture, this bird looks relaxed, the domed=0Ahead=
shape doesn't feel right for YLGU. The head shape in combination=0Awith le=
ss than full chested look typical of YLGUs gives this a Herring=0AGull shap=
e overall.=0A=0AHead streaking on smithsonianus and LBBG is typically heavi=
er than this=0Abut I see many examples of both species with similar head st=
reaking=0Aduring the peak period of head streaking December and January.=0A=
=0AI'd throw this in the bin labelled 'Suspect Lesser Black-backed Gull X=
=0AHerring Gull'. =0A=0ABruce=0A=0A=0A=0ABruce Mactavish=0ASt. John's, Newf=
oundland=0ACanada=0Abruce.mactavish1(AT)nf.sympatico.ca=0A=0A=0A-----Original =
Message-----=0AFrom: NBHC ID-FRONTIERS Frontiers of Field Identification=0A=
[mailto:BIRDWG01(AT)LISTSERV.ARIZONA.EDU] On Behalf Of Allen Chartier=0ASent: =
Saturday, January 06, 2007 11:30 AM=0ATo: BIRDWG01(AT)LISTSERV.ARIZONA.EDU=0AS=
ubject: [BIRDWG01] Interesting gull in Michigan=0A=0ABirders,=0A=0ANot bein=
g much of a gull person, I'm a bit hesitant to post this as I'll=0A=0Aonly =
be able to answer questions about what this bird looked like, and=0Anot =0A=
participate in any further discussions. An interesting gull has been=0Afoun=
d =0Aat the Salem Twp. landfill, Washtenaw Co., Michigan, and has initially=
=0Abeen =0Alabeled a probable Yellow-legged Gull, but in reviewing many int=
ernet =0Aphotos, it would appear perhaps indistinguishable from hybrids bet=
ween =0AHerring and Lesser Black-backed. It would also appear that there is=
=0Acomplete =0Aoverlap in all characters between pure YLGU and hybrid LBBGx=
HERG. All of=0Athe =0Aphotos of hybrids we've found are from Europe, involv=
ing argenteus HERG,=0Aso =0Awe don't really know what a LBBG cross with a s=
mithsonianus HERG would=0Alook =0Alike. How are pure YLGU identified with c=
ertainty in Newfoundland? Only=0Athe =0Aindividuals with screaming yellow l=
egs?=0A=0AA few photos (no spread wing shots are available - whatever that =
would=0Atell =0Aus) are posted at:=0A=0A> http://www.umich.edu/~bbowman/bir=
ds/se_mich/photos.html=0A=0AAllen Chartier=0Aamazilia1(AT)comcast.net=0A1442 W=
est River Park Drive=0AInkster, MI 48141=0AWebsite: http://www.amazilia.ne=
t=0AMichigan HummerNet: http://www.amazilia.net/MIHummerNet=0A=3D=3D=3D=3D=
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=0AEvery day, the hum=
mingbird eats its own weight in food.=0AYou may wonder how it weighs the fo=
od. It doesn't.=0AIt just eats another hummingbird.=0A---Steven Wright =0A=
=0A=0AJoin or Leave BIRDWG01:=0Ahttp://listserv.arizona.edu/cgi-bin/wa?SUBE=
D1=3Dbirdwg01=0A=0AArchives: http://listserv.arizona.edu/archives/birdwg01.=
html=0A=0A=0AJoin or Leave BIRDWG01: http://listserv.arizona.edu/cgi-bin/wa=
?SUBED1=3Dbirdwg01=0A=0AArchives: http://listserv.arizona.edu/archives/bird=
wg01.html=0A=0A=0A=0A=0A
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Subject: Re: Interesting gull in Michigan
From: Mars Muusse <marsmuusse(AT)WANADOO.NL>
Date: 6 Jan 2007 5:05pm
This is a multi-part message in MIME format.
----INCLUDING text/plain MIME SECTION----
Just to have some comparison, I uploaded a picture of a wing-raising
adult Larus michahellis from NW France, last November. I think it nicely
illustrates the amount of black on P7-P10, and it also shows a broad
band on P5 and even a diffuse band on P4. In Herring Gull, one may
expect longer pale tongues on the innerweb of P7-P9. However, when
dealing with hybrid Herring x Lesser Black-backed, this feature is
probably less apparent.
http://www.gull-research.org/ylg/micha00001.html
Cheers,
Mars Muusse
-----Original Message-----
From: NBHC ID-FRONTIERS Frontiers of Field Identification
[mailto:BIRDWG01(AT)LISTSERV.ARIZONA.EDU] On Behalf Of Robert Wallace
Sent: Saturday, January 06, 2007 11:28 PM
To: BIRDWG01(AT)LISTSERV.ARIZONA.EDU
Subject: Re: [BIRDWG01] Interesting gull in Michigan
Greetings - last March we found a gull that is very similar to this
Michigan bird at the dump in Volusia County (Daytona Beach) FL, on the
central Atlantic coast. Mantle color was darker than all of the
surrounding HEGUs, intermediate between them and graellsii LBBGs. Leg
color was pale yellow. There was some light streaking in the crown, when
normally pure YLGUs should be pure white. Another interesting feature
was the string of pearls on p5-8, normally associated with Vega gulls,
but which with yellow(ish) legs are not discussed anywhere in the
literature that I can find, and YLGUs are not described to have this
primary pattern either. A hybrid between LBBG and HEGU was never
considered; is this just a yellow-legged HEGU (but with a darker
mantle?), or a YLGU x ? mix.
To help confuse the issue, I have posted photos at the following link:
http://www.pbase.com/chnuts/volusia_dump_gull_with_yellow_legs
Thanks for any comments,
Bob Wallace
New Smyrna Beach FL
----- Original Message ----
From: Bruce Mactavish <bruce.mactavish1(AT)NF.SYMPATICO.CA>
To: BIRDWG01(AT)LISTSERV.ARIZONA.EDU
Sent: Saturday, January 6, 2007 3:15:25 PM
Subject: Re: [BIRDWG01] Interesting gull in Michigan
Interesting gull. Resembles a number of birds we call Lesser
Black-backed Gull x Herring Gull in Newfoundland. Knowing orbital ring
colour and especially wing tip pattern would say a lot.
The legs do not look yellow enough even considering the photos are all
on the under exposed side. The head streaking, which should be gone even
on the later moulting races (e.g. Azorean) of Yellow-legged Gull in
early January, rarely extends onto the neck on any population of
Yellow-legged Gull.
The upperparts colour looks fine for YLGU. The relatively thick
brightly coloured bill with red of gony bleeding to upper mandible is
good for YLGU. It can occur and is not that rare in smithsonianus
Herring Gulls. Although head shape is highly variable among individual
gulls depending on mood and posture, this bird looks relaxed, the domed
head shape doesn't feel right for YLGU. The head shape in combination
with less than full chested look typical of YLGUs gives this a Herring
Gull shape overall.
Head streaking on smithsonianus and LBBG is typically heavier than this
but I see many examples of both species with similar head streaking
during the peak period of head streaking December and January.
I'd throw this in the bin labelled 'Suspect Lesser Black-backed Gull X
Herring Gull'.
Bruce
Bruce Mactavish
St. John's, Newfoundland
Canada
bruce.mactavish1(AT)nf.sympatico.ca
-----Original Message-----
From: NBHC ID-FRONTIERS Frontiers of Field Identification
[mailto:BIRDWG01(AT)LISTSERV.ARIZONA.EDU] On Behalf Of Allen Chartier
Sent: Saturday, January 06, 2007 11:30 AM
To: BIRDWG01(AT)LISTSERV.ARIZONA.EDU
Subject: [BIRDWG01] Interesting gull in Michigan
Birders,
Not being much of a gull person, I'm a bit hesitant to post this as I'll
only be able to answer questions about what this bird looked like, and
not
participate in any further discussions. An interesting gull has been
found
at the Salem Twp. landfill, Washtenaw Co., Michigan, and has initially
been
labeled a probable Yellow-legged Gull, but in reviewing many internet
photos, it would appear perhaps indistinguishable from hybrids between
Herring and Lesser Black-backed. It would also appear that there is
complete
overlap in all characters between pure YLGU and hybrid LBBGxHERG. All of
the
photos of hybrids we've found are from Europe, involving argenteus HERG,
so
we don't really know what a LBBG cross with a smithsonianus HERG would
look
like. How are pure YLGU identified with certainty in Newfoundland? Only
the
individuals with screaming yellow legs?
A few photos (no spread wing shots are available - whatever that would
tell
us) are posted at:
> http://www.umich.edu/~bbowman/birds/se_mich/photos.html
<http://www.umich.edu/%7Ebbowman/birds/se_mich/photos.html>
Allen Chartier
amazilia1(AT)comcast.net
1442 West River Park Drive
Inkster, MI 48141
Website: http://www.amazilia.net
Michigan HummerNet: http://www.amazilia.net/MIHummerNet
===============================================
Every day, the hummingbird eats its own weight in food.
You may wonder how it weighs the food. It doesn't.
It just eats another hummingbird.
---Steven Wright
Join or Leave BIRDWG01:
http://listserv.arizona.edu/cgi-bin/wa?SUBED1=birdwg01
Archives: http://listserv.arizona.edu/archives/birdwg01.html
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[ << | >> | ^^ ]
Subject: Re: Glaucous-winged age
From: "Norman D.van Swelm" <Norman.vanswelm(AT)wxs.nl>
Date: 6 Jan 2007 5:44pm
Norman:>> As to Dick's question: the few sightings I have from my
colo(u)r-ringed
>> hybrids are all within the normal migratory range of one of their parents
>> and indicate that migratory behaviour is heriditary. Extreme vagrancy is
>> caused by extreme atmospheric conditions.
Phil Pickering wrote:> Certainly much of vagrancy must be due to
environmental conditions, but
> I think you'd need a much, much larger sample size to make anything close
> to the absolute statement Norm is making based on statistical
> correlation.<
Mike Harris's cross-fostering experiments too pointed in the same direction
as my results.
Phil wrote: > Obviously there are exponentially more hybrids than vagrants,
and obviously
> not all hybrids are vagrants.<
You'd be surprised to see the real numbers of vagrants! Make it a hundred or
more for each small migrant spotted.
Phil wrote:>Also isn't there a lot of evidence
> some passerine vagrancy is due to genetic flaws?<
I have have yet to see any evidence.
Norman:>>Like in 1999 the present winter provides a sheer endless succession
of
>>storms from westerly direcions on the Atlantic.
Phil wrote:> Presumably the total percentage of gulls in the northwest
Atlantic
> available to be blown east by storms that also happen to be
> Glaucous-winged is pretty small : ) If this bird showed up in the
> company of dozens of smithsonianus that might make more sense.<
In some years quite a few smithonianus' and other gulls from the new world
have been reported.
Cheers, Norman
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[ << | >> | ^^ ]
Subject: Re: Glaucous-winged age
From: "Norman D.van Swelm" <Norman.vanswelm(AT)wxs.nl>
Date: 6 Jan 2007 6:13pm
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Re: [BIRDWG01] Glaucous-winged age
Alvaro Jaramillo wrote:>Your comment (below) is very confusing to me. How does
the pattern that you are seeing show that migration is hereditary? The hybrid
gulls could very well be following flocks of one of the parental species, making
the pattern you see entirely environmental? <
Alvaro, you have very little faith in nature. When young gulls fledge they are
fully equipped to lead an independent life!
Alvaro wrote:>Extreme vagrancy could also be caused by chance in some case,
just plain old chance. <
Of course but so far in most, if not all, cases it is supported by favourable
atmospheric circumstances as well.
Cheers, Norman
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[ << | >> | ^^ ]
Subject: Re: Glaucous-winged age
From: "Norman D.van Swelm" <Norman.vanswelm(AT)wxs.nl>
Date: 6 Jan 2007 6:26pm
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The first was found in Switzerland and,
Lee Evans wrote:>Norman, I thought this record related to a ring only and no
bird and when I last investigated it, the thought was that the corpse may have
dropped from the undercarriage of an aircraft.<
I would believe it when it had been seen by someone. Since there is not a
shred of evidence to support this story you'd better forget it Lee. It could
have fallen from he sky, of course, as large numbers of birds of all kinds are
shot at airports.
Cheers, Norman
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[ << | >> | ^^ ]
Subject: Re: Glaucous-winged age
From: "Norman D.van Swelm" <Norman.vanswelm(AT)wxs.nl>
Date: 6 Jan 2007 6:42pm
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Nick Lethaby wrote:>I think the presumption that the GWGU arrived across the
Atlantic is not necessarily correct. It could have come through Arctic Russia.
While this isn't necessarily a likely route either, GWGUs are extremely rare E.
of the Rockies in the USA, rarer than species like California Gull or even
Slaty-backed Gull, neither of which has appeared in Europe to my (limited)
knowledge.<
Anything is possible of course. However there is very little open water left
after September in that region. There is another route possible as well. New
World gulls, among them a Glaucous-winged, arriving in NW Africa first before
continuing their journey into Europe!
Norman
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Subject: Re: Glaucous-winged age
From: Alvaro Jaramillo <chucao(AT)COASTSIDE.NET>
Date: 6 Jan 2007 6:55pm
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Norman
Your comment about me having little faith in nature is funny, but it does
not explain the reasoning behind your original statement. I was pointing out
that your comment about the patterns you see with ringed birds "indicating
that migration is hereditary" is not necessarily true, the birds could be
just following other birds and it would result in the same pattern you are
seeing. The pattern you describe of the distribution of ringed hybrid birds
therefore does not differentiate between the two hypotheses: 1) migration is
hereditary 2) migration is not hereditary (=environmental).
Like everything else in life, and in nature/nurture arguments, it is
probably a combination of the two (a third hypothesis). But your use of the
data to say that it indicates that hypothesis 1 is "indicated" is incorrect.
That is all I wanted to point out.
Cheers
Al
Alvaro Jaramillo
chucao(AT)coastside.net
Half Moon Bay, California
Field Guides - Birding Tours Worldwide
www.fieldguides.com
_____
From: NBHC ID-FRONTIERS Frontiers of Field Identification
[mailto:BIRDWG01(AT)LISTSERV.ARIZONA.EDU] On Behalf Of Norman D.van Swelm
Sent: Saturday, January 06, 2007 5:14 PM
To: BIRDWG01(AT)LISTSERV.ARIZONA.EDU
Subject: Re: [BIRDWG01] Glaucous-winged age
Alvaro Jaramillo wrote:>Your comment (below) is very confusing to me. How
does the pattern that you are seeing show that migration is hereditary? The
hybrid gulls could very well be following flocks of one of the parental
species, making the pattern you see entirely environmental? <
Alvaro, you have very little faith in nature. When young gulls fledge they
are fully equipped to lead an independent life!
Alvaro wrote:>Extreme vagrancy could also be caused by chance in some case,
just plain old chance. <
Of course but so far in most, if not all, cases it is supported by
favourable atmospheric circumstances as well.
Cheers, Norman
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