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ID-FRONTIERS for December 14-20, 2003
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Messages are displayed in the order they were received.
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| Subject | From | Date | Time |
| NZ Pluvialis plover | Ross Silcock | Sun, 14 Dec 2003 | 2:06pm |
| Re: Pluvialis plover in New Zealand | Steven Mlodinow | Sun, 14 Dec 2003 | 4:43pm |
| Ovenbird Variations | Bill Elrick | Mon, 15 Dec 2003 | 11:40am |
| More analysis of the DE and NZ Golden Plovers | Jim Barton | Mon, 15 Dec 2003 | 1:09pm |
| Re: More analysis of the DE and NZ Golden
Plovers | Chris Corben | Mon, 15 Dec 2003 | 3:01pm |
| Selasphorus Help | Hugh McGuinness | Tue, 16 Dec 2003 | 10:06am |
| Re: Selasphorus Help | Kevin McGowan | Tue, 16 Dec 2003 | 10:43am |
| Re: Selasphorus Help | Mike Patterson | Tue, 16 Dec 2003 | 11:41am |
| NZ Golden Plover | Steven Mlodinow | Tue, 16 Dec 2003 | 9:12pm |
| Fwd More Paulson Comments | Steven Mlodinow | Tue, 16 Dec 2003 | 9:18pm |
| Golden Plovers: what about the DE bird? | Martin Reid | Wed, 17 Dec 2003 | 5:10am |
| Re: Golden Plovers: what about the DE bird? | Hugh McGuinness | Wed, 17 Dec 2003 | 6:58am |
| Re: Golden Plovers: what about the DE bird? | Joseph Morlan | Wed, 17 Dec 2003 | 7:57am |
| Re: NZ Golden Plover | Chris Corben | Wed, 17 Dec 2003 | 9:12am |
| Pluvialis plovers | Hugh McGuinness | Wed, 17 Dec 2003 | 9:46am |
| mystery nightjar | Vladimir Dinets | Wed, 17 Dec 2003 | 4:39pm |
| More from Dennis Paulson on NZ GP | Steven Mlodinow | Wed, 17 Dec 2003 | 4:42pm |
| Re: Argentatus vs. hyperboreus: hybrid or not ? | Fernando arce | Wed, 17 Dec 2003 | 10:01pm |
| Interesting Flycatcher/Kingbird. | Larry | Wed, 17 Dec 2003 | 10:28pm |
| RE : Golden Plovers: what about the DE
bird? | =?iso-8859-1?Q?Pierr | Thu, 18 Dec 2003 | 2:09am |
| Re: Argentatus vs. hyperboreus: hybrid or not ? | Harry Lehto | Thu, 18 Dec 2003 | 2:33am |
| Re: Argentatus vs. hyperboreus: hybrid or not ? | Dick Newell | Thu, 18 Dec 2003 | 3:20am |
| Re: Argentatus vs. hyperboreus: hybrid or not ? | Peter Adriaens | Thu, 18 Dec 2003 | 4:13am |
| Golden Plover reference | Jerry R. Oldenettel | Thu, 18 Dec 2003 | 9:10am |
| Pacific Golden-Plover in Barbados? | Floyd Hayes | Thu, 18 Dec 2003 | 11:03am |
| Re: Argentatus vs. hyperboreus: hybrid or not ? | Visa Rauste | Thu, 18 Dec 2003 | 11:05am |
| Re: Argentatus vs. hyperboreus: hybrid or not ? | Dick Newell | Thu, 18 Dec 2003 | 11:55am |
| Re: More from Dennis Paulson on NZ GP | Chris Corben | Thu, 18 Dec 2003 | 12:51pm |
| Re: Argentatus vs. hyperboreus: hybrid or not ? | Harry Lehto | Thu, 18 Dec 2003 | 12:57pm |
| Re: Argentatus vs. hyperboreus: hybrid or not ? | Peter Adriaens | Thu, 18 Dec 2003 | 1:06pm |
| Re: Argentatus vs. hyperboreus: hybrid or not ? | Tim Vaughan | Thu, 18 Dec 2003 | 2:17pm |
| Re: Pacific Golden-Plover in Barbados? | julian hough | Thu, 18 Dec 2003 | 5:52pm |
| Re: the NZ GP | matt kenne | Thu, 18 Dec 2003 | 10:53pm |
| Easton's 'Mystery Gull'---again! | Dave DeReamus | Fri, 19 Dec 2003 | 1:28am |
| Re: Argentatus vs. hyperboreus: hybrid or not ? | Dick Newell | Fri, 19 Dec 2003 | 3:32am |
| Re: Argentatus vs. hyperboreus: hybrid or not ? | Millington/BIS | Fri, 19 Dec 2003 | 4:02am |
| Re: Argentatus vs. hyperboreus: hybrid or not ? | Matt Sharp | Fri, 19 Dec 2003 | 8:11am |
| Re: Argentatus vs. hyperboreus: hybrid or not ? | Peter Adriaens | Fri, 19 Dec 2003 | 8:21am |
| RE : Argentatus vs. hyperboreus:
hybrid or not ? | =?iso-8859-1?Q?Pierr | Fri, 19 Dec 2003 | 8:53am |
| Re: RE : Argentatus vs. hyperboreus:
hybrid or not ? | Peter Adriaens | Fri, 19 Dec 2003 | 10:06am |
| Fw: another Golden Plover identification
discussion | matt kenne | Fri, 19 Dec 2003 | 4:22pm |
| More images of the Delaware plover | Anthony Gonzon | Fri, 19 Dec 2003 | 4:42pm |
| Re: Argentatus vs. hyperboreus: hybrid or not ? | Bruce Mactavish | Fri, 19 Dec 2003 | 8:06pm |
| more on mystery nightjar from E Chiapas | Vladimir Dinets | Sat, 20 Dec 2003 | 2:15am |
| Re: Argentatus vs. hyperboreus: hybrid or not ? | Dick Newell | Sat, 20 Dec 2003 | 3:23am |
| Variation in Larus thayeri | Joseph Morlan | Sat, 20 Dec 2003 | 9:19pm |
|
To use email addresses replace '(AT)' with '@'.
This is done to confuse the spam 'bots.
|
[ << | >> | ^^ ]
Subject: NZ Pluvialis plover
From: Ross Silcock <silcock(AT)rosssilcock.com>
Date: 14 Dec 2003 2:06pm
Thanks to those who helpfully shared their expertise re the ID of this
intriguing bird. As some suggested, it may not be identifiable from the
photos, if at all. If you missed the original post, pictures are at my
website, URL below.
Ross
Ross Silcock
P.O. Box 57
Tabor, Iowa, USA 51653
silcock(AT)rosssilcock.com
New Zealand Land and Pelagic Tours
www.rosssilcock.com
[ << | >> | ^^ ]
Subject: Re: Pluvialis plover in New Zealand
From: Steven Mlodinow <SGMlod(AT)AOL.COM>
Date: 14 Dec 2003 4:43pm
----INCLUDING text/plain MIME SECTION----
Greetings All
Acknowledging that IDs can be tough from a single photos, this bird looks to
me to be an American Golden-Plover.
This (the NZ) bird would be exceptionally dull for a Pacific Golden-Plover. I
can't say I've ever knowingly seen one with such a white supercilium.
Furthermore, the primary extension (past tertials) is perfect for American
Golden-Plover. I've found the primary projection most useful on golden-plovers
in WA,
with only a few birds in the inbetween category. And, the primary projection
lines up well with other marks, such as bill size and facial coloration. So, it
seems valid. The only caveat to this that I've encountered is molting birds in
spring (March) in Hawaii, where the primary projection past tertials is more
American GP-like. I, personally, find bill size very difficult to use on a lone
bird (such as in a photo).
Cheers
Steven Mlodinow
Everett WA
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[ << | >> | ^^ ]
Subject: Ovenbird Variations
From: Bill Elrick <belrick(AT)OPTONLINE.NET>
Date: 15 Dec 2003 11:40am
This is a multi-part message in MIME format.
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Hi,
Can anyone give me a little more info on main points of the separations
of Ovenbird variations other than what Pyle, Curson et al. Especially
the Seiurus aurocapillus furvior. I caught a relatively darker bird this
fall in NJ that I assumed may be a furvior. I have photos of it but
wonder if anyone has a quick way to tell the differences. I did have the
drawer out in the ANHM in May but found the skins baffling.
Bill Elrick
NJ
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<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>Hi,<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><span style='mso-spacerun:yes'> </span>Can anyone give
me a little more info on main points of the separations of Ovenbird variations
other than what Pyle, Curson et al. Especially the Seiurus aurocapillus <span
class=GramE>furvior.</span> I caught a relatively darker bird this fall in NJ
that I assumed may be a furvior. I have photos of it but wonder if anyone has a
quick way to tell the differences. I did have the drawer out in the ANHM in May
but found the skins baffling.<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><span style='mso-spacerun:yes'> </span>Bill
Elrick<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><span
style='mso-spacerun:yes'> </span>NJ<o:p></o:p></span></font></p>
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font-family:Arial'><o:p> </o:p></span></font></p>
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[ << | >> | ^^ ]
Subject: More analysis of the DE and NZ Golden Plovers
From: Jim Barton <redwingatfp1986(AT)COMCAST.NET>
Date: 15 Dec 2003 1:09pm
Hello. To my eye, the Delaware bird presents a classic dominica head
and bill. In addition, the longest tertial appears to extend barely beyond
the base of the tail. Four primary tips appear to extend beyond
the tips of the longest tertials. That argues for dominica.
When the image of the NZ bird is lightened quite considerably, the tips
of three primaries can be seen to extend beyond the tip of the longest
tertial. That argues for fulva.
An argument for the DE bird as fulva might be based on the apparent
short distance between the tips of P10 and P9. Compare with the longer
distances from P9 to P8 and P8 to P7.
Folded directly back across the face, the bill of the DE bird about
reaches the back of the eye. The bill of the NZ bird reaches well back of
the eye. That's exactly what I would expect from dominica (generally
larger head,
shorter bill) and fulva (generally smaller head, longer bill).
As Martin Reid has noted, the fact that the tips of the primaries extend
well beyond the tip of the tail does not proved that a golden plover is
dominica. The existence of long-winged fulva is well documented both in
photographs and in the literature.
Martin expresses concern that the longest tertial on the NZ bird does
not extend farther towards the tip of the tail.
Using high magnification, I judge that the the longest tertial actually does
extend all the way to the tip of the tail. In the DE bird, the tip of the
longest tertial appears to extend very slightly beyond the base of the tail
.
In >>Tundra Plovers<< Byrkjedal and Thompson compare the relationship
between the tip of longest tertial and the tip of the tail as follows for
dominica and fulva--
dominica: longest tertial reaches "to inner fourth of tail"
fulva: longest tertial reaches "to outer third of tail or beyond" (1998,
p. 401)
On first examining the photos, I judged that the longest tertial on the
NZ bird reached only 50 to 60 of the way to the tip of the tail; even so,
supposing I was right the first time, that degree of extension argues
strongly for fulva.
By the TP standard for dominica, the tertial extension on the NZ bird would
be twice that of the DE bird and
would far exceed the expected extension for American GP.
Martin calls attention to the difference between the "small teeth" he
expects on the tertials of dominica and the "large teeth" he expects on the
tertials of fulva. If I read the line drawings in TP correctly, the NZ
bird presents
the tertials of an adult fulva, not a juvenile. Martin and others, could
you check on the references below, and whatever other sources you think
appropriate?
To judge from Tundra Plovers pp. 304-307, small white teeth are
characteristic juvenile dominica and fulva alike (p. 304, p. 306) Adult
dominica and fulva both present large white teeth offset by black intervals.
But on dominica, the black intervals are twice the width of the white teeth,
while on fulva, the black intervals are equal in width to the white teeth.
The white teeth are also larger than on dominica (p. 305, p. 307).
The NZ bird thus appears to be presenting the tertials of an adult
Pacific.
Yours,
Jim Barton
redwingatfp1986(AT)comcast.net
Cambridge, MA
US Coordinator, Proact
campaigning for birds and their habitats
before it's too late
www.proact-campaigns.net
[ << | >> | ^^ ]
Subject: Re: More analysis of the DE and NZ Golden
Plovers
From: Chris Corben <corben(AT)HOARYBAT.COM>
Date: 15 Dec 2003 3:01pm
I'd like to make 2 points:
1) Whiteness of supercilium in itself is not a feature suggestive of
American Golden Plover, since both species have blazing white supercilia in
alternate plumage. I have seen a number of presumed fulva in Australia with
blazing white supercilia, but I took these to be birds showing traces of
alternate plumage in an otherwise basic aspect. Can this possibility be
ruled out in the NZ case? What plumage is this bird in, and why does it look
so different from the other bird in the photo? Understanding this issue
seems vital to any attempt to making anything more of this bird.
2) In the few cases where I have been able to compare dominica and fulva
directly, always juvenals, the differences in primary extension was very
evident. However, I have been less impressed by this feature in non-juvenal
birds I have seen (though never in direct comparison). Is it possible that
this feature is less meaningful (or perhaps meaningful in a different way)
in non-juvenal birds? This isn't necessarily a far-fetched idea, since there
seems to be a great deal of analogy between the tertials and the longer
scapulars in shorebirds in general, and it is often obvious that juvenals
have shorter scapulars than adults, so maybe the tertials are shorter in
juvenals as well, and this could confound the meaning of extension by the
primaries past the tertial tips. I also suggest that since tertials, like
the longer scapulars and the central rectrices, are rather modified
feathers, their lengths might be more variable in adult birds than in
juvenals.
Chris Corben
corben(AT)hoarybat.com
[ << | >> | ^^ ]
Subject: Selasphorus Help
From: Hugh McGuinness <hmcguinness(AT)ROSS.ORG>
Date: 16 Dec 2003 10:06am
Hello,
Currently we have two Selasphorus Hummingbirds on eastern Long Island, NY.
I am soliciting commentary about their age, sex and species. Their photos
can be viewed at http://mail.ross.org/~hmcguinness. Once at the site click
on East End Birds and then on the Rarity Photos. (And please excuse the
mess, the site is under development).
Hugh McGuinness
The Ross School
18 Goodfriend Park
East Hampton, NY 11937
hmcguinness(AT)ross.org
631-907-5229
http://mail.ross.org/~hmcguinness
[ << | >> | ^^ ]
Subject: Re: Selasphorus Help
From: Kevin McGowan <kjm2(AT)CORNELL.EDU>
Date: 16 Dec 2003 10:43am
A quick look at the first bird's tail
<http://mail.ross.org/~hmcguinness/East%20End%20Birds/EEBphotos/Selas2.htm>
makes me think it is a Rufous Hummingbird. The outer tail feathers seem
too wide for Allen's. See the photos of specimens on my page at the bottom
of <http://birds.cornell.edu/crows/rufous_hummingbird.htm>.
Kevin
*****************************************************
Kevin J. McGowan
Cornell Laboratory of Ornithology
159 Sapsucker Woods Road
Ithaca, NY 14850
607/254-2432
fax 607/254-2111
kjm2(AT)cornell.edu
http://birds.cornell.edu/crows/
[ << | >> | ^^ ]
Subject: Re: Selasphorus Help
From: Mike Patterson <celata(AT)pacifier.com>
Date: 16 Dec 2003 11:41am
The in-hand photos on #2 are helpful for that one.
It is clearly a female based on the color of R1. The
brightness of the rufous on the breast and the pointiness
of the rects suggest an after-hatch-year bird. R2 appears
to have a bit of a notch which would make this a Rufous
Hummingbird
So, my opinion on #2: AHY F Rufous Hummingbird
#1 is trickier assuming all that red is on R1 (no missing
rects) this has to be a male, thusly the lack of a gorget
(and the apparent bluntness the rects) makes it a hatch-year
bird. The width of the rects is more consistant with Rufous
Hummingbird as is the overall impression of long-tailedness,
but the safe call on this one is _Selasphorus_ sp.
So, #1: HY M _Selasphorus_ sp. (probably RUHU)
Hugh McGuinness wrote:
>
> Hello,
>
> Currently we have two Selasphorus Hummingbirds on eastern Long Island, NY.
> I am soliciting commentary about their age, sex and species. Their photos
> can be viewed at http://mail.ross.org/~hmcguinness. Once at the site click
> on East End Birds and then on the Rarity Photos. (And please excuse the
> mess, the site is under development).
>
> Hugh McGuinness
> The Ross School
> 18 Goodfriend Park
> East Hampton, NY 11937
> hmcguinness(AT)ross.org
> 631-907-5229
> http://mail.ross.org/~hmcguinness
--
Mike Patterson
Astoria, OR
celata(AT)pacifier.com
You've got to accentuate the positive
eliminate the negative
latch on to the affirmative
Don't mess with Mr. In-Between.
- Johnny Mercer
http://www.pacifier.com/~mpatters/bird/bird.html
[ << | >> | ^^ ]
Subject: NZ Golden Plover
From: Steven Mlodinow <SGMlod(AT)AOL.COM>
Date: 16 Dec 2003 9:12pm
----INCLUDING text/plain MIME SECTION----
Greetings All
Comments on the NZ GP from Dennis Paulson
Well, I'll have to agree that the distance from the tip of the
tertials to the tip of the tail is more like Pacific, so that makes
the bird more equivocal to me, and its primary projection is in the
zone in which there seems to be overlap. However, I don't see it as
an undoubted Pacific. In addition, I don't see it as an adult. The
photo was taken on 12 December, well after any adult should be in
full basic plumage, and Pacifics should have a yellowish supercilium
by then. The argument that it could still be showing signs of
alternate plumage seems untenable. I'll admit that a juvenile should
probably have been molting into first-basic plumage by that date,
which means it should be showing adult characteristics, so that
aspect of it is confusing, too.
Unfortunately, I have neither my photos of museum specimens nor my
copy of Tundra Plovers here, so I can't comment on patterns of adult
tertials, but I really would have called this bird a juvenile.
Basic-plumaged individuals of both species typically have paler
tertials than this bird, with black bars at intervals and whitish
fringes. Americans tend to be even plainer than Pacifics. I can't
imagine an adult basic American having tertials like that, and I
don't think Pacific do either. The difference is pretty much the same
as the difference between adult and juvenile yellowlegs tertials. My
book shows a typical basic Pacific, as does the Stint Fan web site.
I'll be interested to hear more about this bird, if further comments
keep coming in. If it's in fact a juvenile, it would be atypical for
a Pacific to have such a white supercilium. Golden-plovers are
frustrating!
I'm always at a disadvantage writing about shorebirds from here,
especially now when all my shorebird books at are home, and it pretty
much has to be from memory (or examination of skins, when that is
relevant; unfortunately, we have no basic-plumaged golden-plovers).
Dennis
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[ << | >> | ^^ ]
Subject: Fwd More Paulson Comments
From: Steven Mlodinow <SGMlod(AT)AOL.COM>
Date: 16 Dec 2003 9:18pm
----INCLUDING text/plain MIME SECTION----
Greetings
This was actually the first email I got from Dennis Paulson on the NZ GP
A bit more certain than the other comments I fwd'd.
Sorry for the confusion. I'll try to post an update.
Cheers
Steven Mlodinow
HI, Steve.
Here's what I wrote Ian Paulsen earlier:
I would have to call that an American. It shows the important field marks of
the white face and long wing and primary projection, and either it's an
American or we can't tell them apart in the field. Having said that, I have to
add
the caveat that maybe sometimes we can't! But this individual doesn't look
intermediate, it looks like an American.
Dennis
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[ << | >> | ^^ ]
Subject: Golden Plovers: what about the DE bird?
From: Martin Reid <upupa(AT)AIRMAIL.NET>
Date: 17 Dec 2003 5:10am
Dear all,
I've enjoyed the discussion on the NZ Pluvialis, and am intrigued by the
differing opinions - I'd still like to get more feedback from Northern
Australia and Korea/Japan - anyone out there???
There has been little public discussion of the Delaware bird:
http://www.udel.edu/dosbirds/photogallery/birdpix/feat4.jpg
- with the two ID-F replies going for dominica, plus three private replies
in the dominica camp for this bird. Yesterday I received a private post
supporting the ID of the DE bird as fulva. It was a rather snotty message
from an observer of the DE bird who was upset that I should question the ID
based upon what I saw in the pics displayed on the Delaware Ornithological
Society's web site! I found this rather amusing, as anyone who puts pics
of "rare" birds on the WWW knows that they are there to be shot at (I
certainly know and accept this from my own experience!)
So I invite anyone with more-revealing photos of the DE bird to make them
available on the WWW - I'd gladly host them if they add to the debate. I
don't care what the DE plover is; I do care about ID frontiers, and for me
the pics at the DOS site look like a dominica; if more photos of it show
fulva features then I need to know this an learn from it.
Also, I'd appreciate more public comment on the DOS images of the DE
Pluvialis; who's for dominica, who's for fulva, and why???
Cheers,
Martin
Martin Reid
Fort Worth, Texas
mailto:upupa(AT)airmail.net
http://www.martinreid.com
[ << | >> | ^^ ]
Subject: Re: Golden Plovers: what about the DE bird?
From: Hugh McGuinness <hmcguinness(AT)ROSS.ORG>
Date: 17 Dec 2003 6:58am
Hello Martin et al.,
I'm no expert on the Pluvialis plovers but this fall I was a co-finder of
NewYork's first record of Pacific Golden Plover (P. fulva). (I'll try to
post some photos of it later this week or early next week but I'm swamped
with two Christmas Bird Counts this weekend). To me the Delaware bird
looks like dominica for the following reasons. The bill looks too thin and
short. In all the photos if the bill length is projected backward onto the
face it only reaches the middle or back of the eye, whereas in fulva it
should go well-beyond the eye. This is true even in the upper right hand
photo which should make the bill appear to be longest. According to data
supplied by Byrkjedal & Thompson in Tundra Plovers this is diagnostic for
it not being fulva. Second the legs look short, especially above the
tarsus; fulva should show a long exposed tibia compared to the tarsus.
Because so much of the leg is below grade in the bumpy soil, the bird in
the photos should appear to have a relatively longer tibia, but to me it
doesn't. Third, four primaries project beyond the tertials and the the
projection of the primaries beyond the tail is fairly long. Fourth the
tertials don't project very far along the tail and they look short to me.
In my view these four major structural marks that all rule against fulva
and actually point towards dominica.
hugh
Hugh McGuinness
The Ross School
18 Goodfriend Park
East Hampton, NY 11937
hmcguinness(AT)ross.org
631-907-5229
http://mail.ross.org/~hmcguinness
[ << | >> | ^^ ]
Subject: Re: Golden Plovers: what about the DE bird?
From: Joseph Morlan <jmorlan(AT)CCSF.ORG>
Date: 17 Dec 2003 7:57am
On Wed, 17 Dec 2003 06:13:40 -0600, Martin Reid <upupa(AT)AIRMAIL.NET> wrote:
>Also, I'd appreciate more public comment on the DOS images of the DE
>Pluvialis; who's for dominica, who's for fulva, and why???
I'll add my vote for dominica. In addition to the many points raised by
others, the pattern of the underparts looks wrong for fulva and correct for
dominica. I.e. it is gray with rows of small pale spots. Isn't fulva
normally streaked on the chest and foreneck?
Incidentally the direct link to the image misses a bit of context including
the date, the name of the photographer and the location, some of which was
provided by Martin Reid in his original analysis. The link to:
http://www.udel.edu/dosbirds/photogallery/main.htm
... then click on the image, provides a little more information. It might
be helpful to know the actual date instead of just October 2003. Was it 1
October of 31 October? American Golden-Plovers often retain much breeding
plumage very late, unlike the earlier molting Pacific Golden-Plovers. E.g.
Jerry Oldenettle has posted an image photographed 25 September, 1985 at
Churchill, Manitoba, Canada here:
http://members.aol.com/oldenet003/index003.html
Photo: http://members.aol.com/oldenet003/AGPv67513_72w.jpg
I recently checked California records of these species and found that Fall
dominica were almost entirely still in full breeding plumage or in juvenal
plumage. Molting adults were all or almost all fulva.
Incidentally, I now hold the opinion that all three birds at the following
site:
http://fog.ccsf.edu/~jmorlan/oct99.htm
... are fulva despite some thoughtful opinion to the contrary.
Lastly, we have had some birds in California that are just unidentifiable
and I suspect that a few may be hybrids. As far as I know, the actual
percentage of hybrids in the contact zone remains unknown. Connors (Auk
100:607-620, 1983) based his findings in part on discriminate function
analysis in which he was able to separate 96% of breeding plumage
specimens. I've often wondered what the 4% that he could not identify
were?
--
Joseph Morlan, Pacifica, CA 94044 jmorlan(AT)ccsf.org
California Birding & new rarities http://fog.ccsf.org/~jmorlan/
California Bird Records Committee http://www.wfo-cbrc.org/cbrc/
[ << | >> | ^^ ]
Subject: Re: NZ Golden Plover
From: Chris Corben <corben(AT)HOARYBAT.COM>
Date: 17 Dec 2003 9:12am
Dennis Paulson wrote:
> In addition, I don't see it as an adult. The
> photo was taken on 12 December, well after any adult should be in
> full basic plumage, and Pacifics should have a yellowish supercilium
Actually it was late November, according to Ross Silcock, not that it makes
any difference. So what's the plumage of the other NZ bird in the photo? I
would suggest it certainly isn't in full basic plumage!
> The argument that it could still be showing signs of
> alternate plumage seems untenable.
Why? It is clearly in molt, so why couldn't it have either retained
alternate eyebrows or new alternate eyebrows?
>I'll admit that a juvenile should
> probably have been molting into first-basic plumage by that date,
> which means it should be showing adult characteristics, so that
> aspect of it is confusing, too.
I think it is well and truly in molt. What I think I am seeing is:
1) some very fresh upper scapulars (surely no doubt about that, and in
itself rules out juvenal plumage at that date)
2) some very worn and eroded longer scapulars, most of which are missing (it
looks to me that there are two long scapulars with black bases and very
pointed tips and partly eroded white teeth. The rest are presumably
missing. The extensive exposure of the black bases of those two feathers
would argue for another row of scaps gone missing above them)
3) many missing wing coverts resulting in exposure of the bases of some of
the longer medians (the bases of the large, browner-looking wing coverts
have presumably been exposed by the loss of the row of coverts above them)
4) a mixture of browner and greyer feathers on the underparts suggestive of
active molt there.
I suggest that the scalloped look to the underparts is not due to juvenal
plumage, but due to vey fresh feathers of another generation. It is a common
feature of shorebirds that new feathers often have broad pale fringes which
obscure the underlying pattern until some wear has occurred. That's what it
looks like to me.
The tertials look markedly worn at the tips, and might be half an inch
shorter than they were when fresh, so any interpretation of primary
extension past the tertials needs to bear that possibility in mind.
The wingtips reach different points, with the near wing (above) looking
shorter. This shows that the bird is somewhat twisted away from the viewer
at the rear, which would also shorten the apparent length of the tail. But
since the bird is in molt, do we know that the primaries are fully grown?
Until we really understand what this bird's molt is all about, we should be
very careful of drawing any conclusions that depend on the color of the
bird. At the very least, it is pointless trying to assess its plumage
characters as if it is a juvenal!
Chris Corben
corben(AT)hoarybat.com
[ << | >> | ^^ ]
Subject: Pluvialis plovers
From: Hugh McGuinness <hmcguinness(AT)ROSS.ORG>
Date: 17 Dec 2003 9:46am
Hello,
As promised earlier today, I have posted photos of New York's Pacific
Golden Plover from September, as well as an early draft of the forthcoming
paper in 'The Kingbird.' They can be viewed at
http://mail.ross.org/~hmcguinness. Once at my stunning red home page click
on 'East End Birds' and then on 'Rarity Photos' to reveal the link to the
Pacific Golden Plover.
hugh
Hugh McGuinness
The Ross School
18 Goodfriend Park
East Hampton, NY 11937
hmcguinness(AT)ross.org
631-907-5229
http://mail.ross.org/~hmcguinness
[ << | >> | ^^ ]
Subject: mystery nightjar
From: Vladimir Dinets <v0v04ka(AT)HOTMAIL.COM>
Date: 17 Dec 2003 4:39pm
Dear All,
Here are two video stills of a nightjar observed near Chiapas/Guatemala border
north from Lagunas de Montebello, in hill rainforest. I initially
identified it as Yucatan nightjar Caprimulgus badius based on facial markings,
but wing pattern doesn't seem right. Besides, it would be a little bit
outside known range for C. badius.
http://dinets.travel.ru/mexnightjar1.jpg
http://dinets.travel.ru/mexnightjar2.jpg
Any comments?
Vladimir Dinets
P.S. I just came back from a trip - drove from Colorado to Nicaragua and back,
spending most time in Central and Southern Mexico and
Guatemala. I'd be glad to share any information.
[ << | >> | ^^ ]
Subject: More from Dennis Paulson on NZ GP
From: Steven Mlodinow <SGMlod(AT)AOL.COM>
Date: 17 Dec 2003 4:42pm
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Hi, Steve.
I assume you've seen the other stuff that people wrote about the
bird. The comments about how far the tertials reach relative to the
tail tip carries some weight, as it may be that that in fact is a
better field mark than wing projection or primary projection per se.
The shorter tertials in AMGP are a primary cause for the longer
primary projection, and that seems to hold up in a lot of photos I've
looked at. The bird is now in the category of "confusing" or
"equivocal," as it certainly looks like an American, but the tertial
character puts it firmly in the Pacific morphotype. This leaves me
basically confused!
To try to alleviate my confusion, I once again got out all of our
golden-plover specimens and perused them. Now I'm even more confused!
We recorded wing length and primary projection on all the specimens
collected in recent years, and I just made up a table with these data
that shows the extent of the tertials relative to the tip of the
longest primary does NOT distinguish the species (tertials reached
anywhere from the tip of primary 6 to two-thirds of the way to
primary 8, averaging farther in fulva but with overlap). Nor does the
wing measurement, except very generally (the longest wings are on
dominica, the shortest on fulva, but surprisingly much overlap).
However, plumage readily divides our 10 recently collected juveniles
into 5 of each species, and if I use plumage, then those structural
characters don't work all that well, or should I say, they are a bit
sloppy. The color pattern of the NZ bird isn't definitive enough for
me to put it in one species or the other, except for the white
supercilium, which certainly indicates American (if in fact it's a
juvenile, which I think it is).
So, although a number of people, me included, have stated that the
wing characters may be more dependable than plumage characters, I
don't believe that any more. Yes, they are indicative, but they are
certainly not definitive. Birders love DEFINITIVE, but what we get in
all too many instances is INDICATIVE!
I then got out all of our wing specimens, and indeed it looks as if
the tertials are longer on fulva on the average, in both adults and
juveniles, but again there's overlap. I've put typical individuals on
our web site (just added the adults)
http://www.ups.edu/biology/museum/wingphotos.html, and the
differences show up.
I don't know if you're following the discussion on BIRDWGO1, but if
you are you've seen the arguments of several people for this bird
being an adult. I just looked at it again, brightened and blew up the
two photos and sharpened the focus as much as I could without losing
all resolution, and I have to say I don't see any definitive (there's
that word again) evidence that the bird is in molt! I don't agree
with the argument that because you can see feather bases, the bird is
in molt. I didn't know any other way to check this than by looking at
photos of shorebirds, and in my 1993 book, there are a fair number of
juvenile shorebirds that show exposed feather bases and disheveled
feathers, especially the lower scapulars. Some examples: Least
Sandpipers (p. 273), Curlew Sandpiper (308), Buff-breasted Sandpiper
(317).
Furthermore, even if the tertials were "markedly worn at the tips"
(that's not at all obvious to me), that is not evidence that it's not
a juvenile. We have juvenile specimens from as late as late October,
and the tertials of some of them are distinctly worn, especially
toward the tip. Additional evidence for them being juvenile tertials
is that when the adults have brightly notched tertials, the notches
disappear toward the tips of the feathers, which are continuously
fringed with golden. This bird's pattern is typical of juveniles.
I don't know what to think about the golden scapulars. Pacifics can
have brightly marked scapulars in any plumage, while they're more
typical of Americans in alternate plumage but sometimes in juvenal
plumage. I wish I could see the bird a bit better on my computer, as
I can't see clearly some of the details that Chris Corben pointed out
("two long scapulars with black bases and very
pointed tips and partly eroded white teeth"). If those are exactly as
he described, that indeed points away from it being a juvenile. But I
just finished looking at a large series of wings, adult and juvenile,
and this bird's plumage patterns are perfect for a juvenile and
definitely not perfect for an adult, either in covert or tertial
pattern. Scapular pattern is also different, sometimes very
different, in adults and juveniles, but there may be overlap.
To me, this bird shows no evidence of being in primary molt either,
and it shouldn't be in the late stages of that molt (thus influencing
apparent wing length) in late November at that latitude. According
to the BNA account (Johnson & Connors 1996), primary molt finishes in
March in Australia (but they do mention that it finishes in December
in Hawaii). Also, the primary tips not being exactly together doesn't
necessarily tell us anything about the bird's orientation, as birds
don't always hold both of their wings in exactly the same position.
Think of the way a bird's wings fold, and try to imagine that they
could be folded exactly the same, with the position involving three
different joints. It's actually quite common for them to be
unequal-looking, even when the bird is perfectly perpendicular to
your line of sight.
I don't have Tundra Plovers here so can't comment on Byrkjedal's
drawings, but after having examined numerous specimens, I'll go with
them rather than a drawing as a resource. This bird still looks like
a juvenile to me.
Ian, feel free to forward this, and thanks for keeping me informed
about the discussion.
Dennis
--
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[ << | >> | ^^ ]
Subject: Re: Argentatus vs. hyperboreus: hybrid or not ?
From: Fernando arce <fernand_arce(AT)YAHOO.ES>
Date: 17 Dec 2003 10:01pm
Hola Menotti:
about your bird, I think it could be a 2º winter hybrid, but i have no field
experience with this birds and not so much with nominate or northern
argentatus (it´s realyy scarce here in the north of spain). If your bird is
finally id as a pure herring, i would like to receive the comments that the
great experts will send to you. to me this primaries, eye colour, and bill
pattern sounds very nice for an hibrid as well as the dirty pale grey tone
(with no bulish tinges) of the recentrly moulted mantle feathers). Tertials
sound somewhat strong patterned while primaries are very dull brown (sorry I
mean marrón pálido or pàle brown, maybe sometimes easy in spanish for me),
and despite it´s dificult to asses in only one shot, the bird appear to be a
very big gull (bigger than a Tipical yellow legged) and the tail appear to
be very pale brown (maybe caoba?) that I could expext for a northern herring
here ¿What about H. Letho opinion?.
All the best.
Fernando
Cantabria (spain)
----- Original Message -----
From: Menotti Passarella <menotti.passarella(AT)LIBERO.IT>
To: <BIRDWG01(AT)LISTSERV.ARIZONA.EDU>
Sent: Thursday, December 04, 2003 9:41 AM
Subject: [BIRDWG01] Argentatus vs. hyperboreus: hybrid or not ?
> I think this photo taken in Italy is very interesting:
>
> http://www.geocities.com/migliarino2004/Gabb17-6.JPG
>
> Cheers
>
> Menotti Passarella, Italy
[ << | >> | ^^ ]
Subject: Interesting Flycatcher/Kingbird.
From: Larry <birderlm(AT)BELLSOUTH.NET>
Date: 17 Dec 2003 10:28pm
This is a multi-part message in MIME format.
----INCLUDING text/plain MIME SECTION----
After following the discussion of the New York Kingbird this made me dig
through my closet for these photos. I hate to post such poor photos but
this is all that I have. I took these photos in Florida sometime in March
of 1996. This bird was on phone wires along with Scissor-tailed Flycatchers
and Western Kingbirds. The first thing that I noticed was a yellow belly
and a fairly long odd looking tail. At the time I thought gee, this sure
looks like a Scissor-tailed Flycatcher and Western Kingbird mix. I did not
notice any pink anywhere on the bird, just yellow. I sure wish that I had a
digital camera at that time to be able to get some digiscoped pictures.
This could be another U.F.O.
http://www.southfloridabirding.com/FC1.jpg
http://www.southfloridabirding.com/FC2.jpg
http://www.southfloridabirding.com/FC3.jpg
http://www.southfloridabirding.com/FC4.jpg
http://www.southfloridabirding.com/FC5.jpg
Larry Manfredi
Homestead, FL.
E-mail: birderlm(AT)bellsouth.net <mailto:birderlm(AT)bellsouth.net>
http://www.southfloridabirding.com <http://www.southfloridabirding.com/>
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[ << | >> | ^^ ]
Subject: RE : Golden Plovers: what about the DE
bird?
From: =?iso-8859-1?Q?Pierre-Andr=E9_CROCHET?= <crochet(AT)CEFE.CNRS-MOP.FR>
Date: 18 Dec 2003 2:09am
Dear all,
I thought I would try to comment on both the NZ and DE plovers. First, I must
say I have limited field experience with both dominica and fulva, having seen
only vagrants in Europe. But I've been looking at some photos on the net, quite
extensively these past weeks, as I've been more and more interested in this
subject. And after all, a 'photo" experience might not be all bad for judging
photos.
Of course, I'll be quick on the DE bird which is in my opinion a clear (even if
bright) dominica. But this is no surprise. Just to add one vote.
Now, the NZ plover:
First, the age. I'm pretty sure the bird is a 1st winter (1cy). The pattern of
the breast feathers is typical of juvenile plovers. According to the European
literature, at least for Golden plover, the scapulars are moulted during the
first autumn / winter, but the underparts feathers are retained and allow ageing
during the winter. The chest feathers in juvenile have a thin dark shaft and
some grey bars, creating a barred pattern. This is clearly visible on the NZ
bird and is sufficient to make it a 1cy. Ad have the breast feathers with no
bars but a mores solid dark blob instead of thin dark shaft.
Also, the wing coverts appear to be all the same age, and quite worn, compatible
with an old juv wing. Scapulars are clearly of two generations, with old grey
and white feathers (especially lower scaps) and recent, golden and black
feathers. These grey and white lower scaps are clearly old and worn. So they
must be the feathers that this bird had a few months ago. And they are clearly
of juvenile type (dark center with pale notches). So the old scaps are of
juv/non breeding type, giving further support to the age as 1cy. The tertials
are more difficult to use (for me) because ad fulva have a confusing variety of
tertial pattern (at least based on the pictures I have), some quite similar to
the pattern of the NZ bird. But the NZ bird has tertials that fit perfectly the
pattern of juveniles. The dull colour is apparently what we should expect of
these juv feathers after a few months.
Now the species: I have less confidence here, but my gut feeling is clearly
fulva. The head pattern shows the isolated dark spot on the lower cheeks of
fulva, the golden cap is pro fulva, the long bill is pro fulva (although I have
pictures of dominica with very long bill perfect for fulva...), the body shape
(quite round, not too elongated) is pro fulva, the tertial length relative to
primary length is more typical of fulva (and is certainly NOT outside the
variation of fulva!). I think the few unusual characters (and they are not that
many) all fall easily within the variation of fulva.
I think the striking difference between this bird and the bird next to it (on
the left) is explained by different age and individual variation, not by
different species.
Best,
Pierre
Pierre-André Crochet
CEFE-CNRS
1919, route de Mende
34293 Montpellier cedex 5
France
tel: + 33 6 07 32 60 75
fax: + 33 4 67 41 21 38
crochet(AT)cefe.cnrs-mop.fr
-----Message d'origine-----
De : NBHC ID-FRONTIERS Frontiers of Field Identification
[mailto:BIRDWG01(AT)LISTSERV.ARIZONA.EDU] De la part de Martin Reid
Envoyé : mercredi 17 décembre 2003 13:14
À : BIRDWG01(AT)LISTSERV.ARIZONA.EDU
Objet : [BIRDWG01] Golden Plovers: what about the DE bird?
Dear all,
I've enjoyed the discussion on the NZ Pluvialis, and am intrigued by the
differing opinions - I'd still like to get more feedback from Northern
Australia and Korea/Japan - anyone out there???
There has been little public discussion of the Delaware bird:
http://www.udel.edu/dosbirds/photogallery/birdpix/feat4.jpg
- with the two ID-F replies going for dominica, plus three private replies
in the dominica camp for this bird. Yesterday I received a private post
supporting the ID of the DE bird as fulva. It was a rather snotty message
from an observer of the DE bird who was upset that I should question the ID
based upon what I saw in the pics displayed on the Delaware Ornithological
Society's web site! I found this rather amusing, as anyone who puts pics
of "rare" birds on the WWW knows that they are there to be shot at (I
certainly know and accept this from my own experience!)
So I invite anyone with more-revealing photos of the DE bird to make them
available on the WWW - I'd gladly host them if they add to the debate. I
don't care what the DE plover is; I do care about ID frontiers, and for me
the pics at the DOS site look like a dominica; if more photos of it show
fulva features then I need to know this an learn from it.
Also, I'd appreciate more public comment on the DOS images of the DE
Pluvialis; who's for dominica, who's for fulva, and why???
Cheers,
Martin
Martin Reid
Fort Worth, Texas
mailto:upupa(AT)airmail.net
http://www.martinreid.com
--
passerelle antivirus du campus CNRS de Montpellier
--
--
passerelle antivirus du campus CNRS de Montpellier
--
[ << | >> | ^^ ]
Subject: Re: Argentatus vs. hyperboreus: hybrid or not ?
From: Harry Lehto <hlehto(AT)OJ287.ASTRO.UTU.FI>
Date: 18 Dec 2003 2:33am
On Thu, 18 Dec 2003, Fernando arce wrote:
Terve Menotti and Fernando,
Per Fernando's request, here's my opinion after some discussion
with the other H. Lehto. This is a difficult bird. When was the bird
photographed? Assuming it was photographed earlier this month (original
inquiry on Dec 4 - although I'm a bit surpised to see an apparently fully
hooded L rid in the same picture, but that could be an effect of looking
the L rid straight from rear).
The L argentatus below refers to the variation I see here in SW Finland.
1) The bird appears very L argentatus-like in shape. (The size
difference is to to difference in distance.) This bird appears
not to be a normally colored L argentatus (not even of the very pale
type). The coverts on both sides appear very pale. To me
this indicates one of two alternatives leuctistic (possibly white spotted
type) Herring gull with resticted pale areas, or a hybrid.
I would very much like to see a photo from the side - or a flight shot.
2) The eye is OK for L argentatus, and the bill is within the variations
of L argentatus of this age.
3) The white tips of the primaries could point towards a L hyp, but they
also do occus in L argentatus.
4) This picture of has no clear single field mark pointing unequivocally
towards a hyporboreus (eg. detailed patterns of coverts). A side picture
would also show the "breastiness" of this bird.
5) But there are a few points that suggest that this could be a hybrid.
a) Tertials (2 lower ones on both sides) are quite pale and show thin
barring perpendicular to the dark shaft streak.
b) base color of the primaries is quite pale.
c) mantle color is quite pale (compare to the adult behind this bird)
d) The rather white coverts show some thin barring suggesting L hyp.
I feel a bit uncomfortable to call this bird a definite L argentatus. If
it is an argentatus it is a leucistic bird. This is difficult to rule out
- and they do exist. On the other hand I feel that this could be a
hybrid, but if it is such, it is quite L argentatus-like. I would really
like to see a side shot to see the covert field, claws, the breast, and
the wing length. I feel that a hybrid is the more likely
possibility, but by no means with 90% certainty.
Harry J Lehto
hlehto(AT)utu.fi
> ----- Original Message -----
> From: Menotti Passarella <menotti.passarella(AT)LIBERO.IT>
> To: <BIRDWG01(AT)LISTSERV.ARIZONA.EDU>
> Sent: Thursday, December 04, 2003 9:41 AM
> Subject: [BIRDWG01] Argentatus vs. hyperboreus: hybrid or not ?
>
>
> > I think this photo taken in Italy is very interesting:
> >
> > http://www.geocities.com/migliarino2004/Gabb17-6.JPG
> >
> > Cheers
> >
> > Menotti Passarella, Italy
>
--
_____________________________________________________________________
Dr. Harry J Lehto Assistant Professor, Docent
Tuorla Observatory Yliassistentti, Dosentti
Turku University Tel: +358-2-2744263
Väisäläntie 20 Fax: +358-2-2433767
21500 Piikkiö, FINLAND email: hlehto(AT)utu.fi
______________________________________________________________________
[ << | >> | ^^ ]
Subject: Re: Argentatus vs. hyperboreus: hybrid or not ?
From: Dick Newell <dick.newell(AT)MACUNLIMITED.NET>
Date: 18 Dec 2003 3:20am
Re: http://www.geocities.com/migliarino2004/Gabb17-6.JPG
The choice here is between leucistic (European) Herring Gull and hybrid
Glaucous x Herring Gull.
In this second winter bird, the broken eye-ring is a pro-hybrid feature, as
is the overall paleness. However, the latter could also be explained by
leucism, as could the grey primaries. The pink at the base of the bill would
be quite normal in a Herring Gull at this age. The head and bill-shape is
typical Herring Gull. So I am not sure there is enough in this bird to hang
it on the hybrid peg (at least not with any certainty).
Here in the east of England, and also in Norway and Finland, 1st winter
"Herring" Gulls showing a number of traits of Glaucous Gull are quite
common, see:
http://www.magikcircle.com/birds/image.asp?title_id=478 and links therein)
The traits exhibited include some or all of:
a broken eye-ring
pale fringes with sub-terminal chevrons in the primaries
translucent primaries
reduced or no tail-band
frilly scapulars
heavily patterned tertials
overall paleness
excessive pink at the base of the bill
head and bill-shape
overall shape of bird
It is also not uncommon to see adult "Herring" Gulls with thayerii wing-tips
or much reduced black in the wing-tips, but I have never seen one with grey
in the wing-tips. Could it be that these 1st winters and adults have the
same ancestry?
Although Glaucous x Herring hybrids are known to be common in Iceland, My
guess is that these birds are almost certainly coming from Northern Norway
somewhere. They have the migratory behaviour of argentatus and some of the
appearance of Glaucous Gull. There is another hybrid zone up there somewhere
as with Kumlien's Gull (Iceland x Thayer's) and Olympic Gull (Western x
Glaucous-winged) - we just don't have a name for them (suggestions on a
postcard please! - not Nelson's Gull - that is a different animal)
Cheers
Dick Newell, Cambridge, UK
[ << | >> | ^^ ]
Subject: Re: Argentatus vs. hyperboreus: hybrid or not ?
From: Peter Adriaens <peter.adriaens(AT)dutchbirding.nl>
Date: 18 Dec 2003 4:13am
> On Thu, 18 Dec 2003, H. Lehto wrote:
>
> On the other hand I feel that this could be a
> hybrid, but if it is such, it is quite L argentatus-like.
Yes, and this is what bothers me. Most of the European putative hybrids
Glaucous x Herring Gull that have been posted to this list in the last few
years, have been most similar to Herring Gull (of the race argentatus).
Why ? Could it not be that they simply are pale Herring Gulls ?
Hybrids are supposed to show characters of both parents, and to be quite
variable. This means that some will indeed be most similar to Herring
Gull, but others will be most similar to Glaucous Gull. This certainly
seems to be the case in Iceland, and also in North America, where
"Nelson's Gulls" are often quite similar to Glaucous Gull.
If such hybrids are indeed regular on the European continent, wouldn't we
see a lot more birds that are similar to Glaucous Gull?
Take Norway for an example; the excellent "Norwegian Gull Page" now holds
a collection of photographs of 23 different "possible and probable
Glaucous x Herring Gull hybrids"; see
http://cyberbirding.uib.no/gull/ind_ufo.php. Of these, no less than 20
look most similar to Herring Gull! The pigment in their primaries is
extensive, and the barring on the upperparts and wingcoverts is as thick
and bold as in the average argentatus.
To me, this improper balance suggests that many of these 'Herring Gull
types' are just that -- pale Herring Gulls. Is there any reason to think
otherwise ?
Best regards,
Peter
[ << | >> | ^^ ]
Subject: Golden Plover reference
From: "Jerry R. Oldenettel" <Borealowl(AT)AOL.COM>
Date: 18 Dec 2003 9:10am
----INCLUDING text/plain MIME SECTION----
Joe, et al, I deeply apologize to all for the erroneous date on my golden
plover photo as 25 Sept. The photograph was taken on 25 June, 1985 at
Chruchill.
I have numerous fall/winter photos of both dominica from New Mexico/Arizona
and fulva from Maui that I could post if they would be of use to the
discussion.
By the way, I've looked at Shilock's page and don't seem to be able to locate
the photos of the NZ bird. Any hints?
Jerry R. Oldenettel
borealowl(AT)aol.com
----DELETED text/html MIME SECTION----
[ << | >> | ^^ ]
Subject: Pacific Golden-Plover in Barbados?
From: Floyd Hayes <floyd_hayes(AT)YAHOO.COM>
Date: 18 Dec 2003 11:03am
Dennis Paulson's comments are disturbing. While on the
subject, I'd be interested in comments on a presumed
Pacific Golden-Plover in Barbados:
http://www.geocities.com/secaribbirds/bapacificgolden-plover
I know few details about the bird, including the date
it was photographed. It was apparently captured (shot
and wounded?) by local hunters and caged, then
examined later by local birders Martin Frost and Ed
Massiah. It was in full alternate plumage when they
showed it to me in July 2000 (I think Martin has
additional photos, and they have measurements as
well).
-Floyd
__________________________________
Do you Yahoo!?
New Yahoo! Photos - easier uploading and sharing.
http://photos.yahoo.com/
[ << | >> | ^^ ]
Subject: Re: Argentatus vs. hyperboreus: hybrid or not ?
From: Visa Rauste <Rauste(AT)CC.HELSINKI.FI>
Date: 18 Dec 2003 11:05am
Two more individuals of first winter "pale Gulls", photographed in
Tampere, SW Finland, in November, can be seen at
http://www.helsinki.fi/~rauste/gulls/tomppa.html (6 pictures)
http://www.helsinki.fi/~rauste/gulls/tomppa2.html (5 pictures)
--
Visa Rauste
Visa.Rauste(AT)Helsinki.FI, tel +358-9-19144146
[ << | >> | ^^ ]
Subject: Re: Argentatus vs. hyperboreus: hybrid or not ?
From: Dick Newell <dick.newell(AT)MACUNLIMITED.NET>
Date: 18 Dec 2003 11:55am
On 18/12/03 11:13 am, "Peter Adriaens" <peter.adriaens(AT)DUTCHBIRDING.NL>
wrote:
> To me, this improper balance suggests that many of these 'Herring Gull
> types' are just that -- pale Herring Gulls. Is there any reason to think
> otherwise ?
> Best regards,
> Peter
>
Well Peter, you may be right, but I think there is a rational argument as to
why they are not "pure" Herring Gulls. Of course one could get into a
semantic argument about what one means by a Herring Gull - or even a species
when it comes to gulls. If I understand Pierre André's Auk paper - are not
all of these gulls just mixtures?
If one first considers Kumlien's Gull it is notable that it is more variable
than supposed "pure" species. Although it is now generally accepted that it
is a mixture of Iceland and Thayer's Gulls, the majority of them are more
similar to Iceland Gull than they are to Thayer's in both plumage and
structure.
These supposed Glaucous x Herring types are certainly very variable, from
those with very obvious Glaucous Gull influence to those which look more
like Herring Gulls (the majority).
Why should most of them look more like one species than the other? This
could simply be because the introgression of A into B will produce more
B-type offspring than the other way round because further crosses are more
likely to be with B and so B-type appearance will dominate.
Further, in the case of Glaucous x Herring hybrids, it could well be that
the ones that look more like Glaucous Gulls also have more Glaucous-like
migratory behaviour and are less likely to move south.
When someone finds a corps or catches of one of these things, I suggest they
pluck some feathers and send them to Pierre-André. Unfortunately one might
have to test quite a few before finding one with the right set of female
ancestors!
I hope this makes sense.
Dick, Cambridge, UK
[ << | >> | ^^ ]
Subject: Re: More from Dennis Paulson on NZ GP
From: Chris Corben <corben(AT)HOARYBAT.COM>
Date: 18 Dec 2003 12:51pm
Gooday Dennis and all
> I then got out all of our wing specimens, and indeed it looks as if
> the tertials are longer on fulva on the average, in both adults and
> juveniles, but again there's overlap. I've put typical individuals on
How are you measuring the tertials? Is this relative to the primaries, or
are you actually measuring the feathers?
> that word again) evidence that the bird is in molt! I don't agree
> with the argument that because you can see feather bases, the bird is
> in molt. I didn't know any other way to check this than by looking at
> photos of shorebirds, and in my 1993 book, there are a fair number of
> juvenile shorebirds that show exposed feather bases and disheveled
> feathers, especially the lower scapulars. Some examples: Least
> Sandpipers (p. 273), Curlew Sandpiper (308), Buff-breasted Sandpiper
> (317).
Unfortunately, I have no ready access to ANY published photos including
Dennis' excellent book. So I have to go from memory.
I am not trying to say that exposure of the bases, in itself, demonstrates
that feathers are missing. It's at least partly a matter of degree, and
partly a matter of seeing things in context. But surely there can be no
doubt that the big feathers with extensively black bases, showing just below
the brightly fringed upper scapulars, must be examples of the longer
scapulars of one of the lower (=posterior) rows. So where are the rest of
them? Irrespective of my interpretation of their shapes, there aren't nearly
enough of them visible to represent a full set.
As to their shapes, they look to me like feathers highly abraded so that
they have long, attenuated tips, a common thing to happen with the longer
scapulars on shorebirds. But I could be wrong about that, since it is hard
to decide where these feathers end, and the underlying wing coverts start.
But it doesn't make any difference to the point that lots of these feathers
are missing.
The wing coverts also show a couple of extensively exposed feathers which I
interpret to be median coverts. These are the feathers which look very brown
with white teeth. To me, their bases look so exposed that I have to conclude
that the more upper (=anterior) row/s which normally cover their bases, are
missing, or maybe growing in. You can see wing coverts above these which
have blacker centres, suggesting, but not proving, that these are feathers
of a later generation.
To me, it looks like there are lots of scapulars, and lots of wing coverts
missing, or at least, not fully grown.
In any case, how could juvenal upper scapulars look so fresh in late
November? To my eyes, these look like a new generation of feathers.
> Furthermore, even if the tertials were "markedly worn at the tips"
> (that's not at all obvious to me), that is not evidence that it's not
> a juvenile. We have juvenile specimens from as late as late October,
I wasn't trying to argue that the tertials aren't juvenal feathers. My point
was that if they are worn at the tips, their lengths may give a deceptive
impression of primary projection.
> in Hawaii). Also, the primary tips not being exactly together doesn't
> necessarily tell us anything about the bird's orientation, as birds
> don't always hold both of their wings in exactly the same position.
> Think of the way a bird's wings fold, and try to imagine that they
> could be folded exactly the same, with the position involving three
> different joints. It's actually quite common for them to be
I don't dispute that, but surely it raises doubts. The bird does look
swivelled away at the rear to me, anyway, though I'm not quite sure why I
think that. But the fact that the primary tips are not equal, does at least
make you think that orientation could be making interpretation unreliable.
If you look at Howell et al 2003 (Condor, 105, part 4: 635 - 653), it
suggests that the Pluvialis plovers might have a Simple Alternate Strategy,
citing a paper by Howell and Pyle (2002, Western Birds, 33:268-270). If
true, this would mean that the first post-juvenal molt would be the molt
which produces 1st Alternate plumage. If this was such a case, then it could
be that the eyebrows have already molted into new, 1st Alternate feathers.
Hence white.
Another possibility is that the eyebrows are still juvenal feathers which
have faded to white. I actually can't see the slightest problem with that
idea. I have seen a specimen, alleged to be of fulva, in the Cal Academy
collection, which showed very little hint of yellow in late September! I
also watched, at some length, a bird in California which was widely touted
as a juvenal AMGP but which looked structurally identical (to my eyes) to
the two obvious PAGPs next to it. It was being IDed as AMGP by color. But
when the wind ruffled the breast feathers, you could see lots of golden
color hidden underneath, but not visible at the surface. The eyebrows looked
white.
The NZ bird does seem to be quite yellow around the face, and with yellow
tints in the upper breast. Would this be consistent with AMGP?
Pierre-André Crochet wrote:
>The chest feathers in juvenile have a thin dark shaft and some grey bars,
>creating a barred pattern. This is clearly visible on the NZ bird and is
sufficient >to make it a 1cy.
But I really doubt these are juvenal feathers. My impression is that most of
the breast is fresh and grey, while much of the flanks are of older, browner
feathers. Don't others see this too?
>Scapulars are clearly of two generations, with old grey and white feathers
>(especially lower scaps) and recent, golden and black feathers.
Could these "old grey and white feathers " be those two prominent feathers
which I think are median coverts?
Whatever, I think the most important point is that the stark white
supercilium in no way argues against the bird being a PAGP. And I argue that
the grey breast feathers are also not a good argument either way. We have to
be careful not to read too much into features which apply best to birds in
fresh juvenal plumage, since this isn't a bird in fresh, juvenal plumage.
Cheers, Chris.
Chris Corben
corben(AT)hoarybat.com
[ << | >> | ^^ ]
Subject: Re: Argentatus vs. hyperboreus: hybrid or not ?
From: Harry Lehto <hlehto(AT)OJ287.ASTRO.UTU.FI>
Date: 18 Dec 2003 12:57pm
> Peter wrote:
> > To me, this improper balance suggests that many of these 'Herring Gull
> > types' are just that -- pale Herring Gulls. Is there any reason to think
> > otherwise ?
No reason in my opinion, I whole heartedly agree with you.
And Dick replies to Peter (I'm picking certain points here):
> Well Peter, you may be right, but I think there is a rational argument as to
> why they are not "pure" Herring Gulls. ...
>...
> These supposed Glaucous x Herring types are certainly very variable, from
> those with very obvious Glaucous Gull influence to those which look more
> like Herring Gulls (the majority).
(see comments above)
> ...
> Why should most of them look more like one species than the other?
>...
Here's an rough drawing (below). Say you have a conbination of traits of
Herring Gull and Glaucous Gull. In Herring Gull the variation in the plumage
patterns is very large. In Glaucous Gull it is relatively small.
So naturally the ones on the right on the graph (letters AA) below may
look quite glaucous-like in some features, but there is a continuous cline
from pale to very dark herring gulls. From these palest Herring Gulls
there is an obvious gap to hybrids and then AGAIN from hybrids to
glaucous gulls. If the variation in argentatus is large then it is clear
that the true hybrids (HH) look quite glaucous like on average.
Because of parentage and the variation of within argentatus there are some
hybrids that are more herring gull-like than the "average" hybrids. The
variation within the hybrids is in my experience considerably smaller
than within argentatus and a bit larger than within glaucous gull.
AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA HH G
> Further, in the case of Glaucous x Herring hybrids, it could well be that
> the ones that look more like Glaucous Gulls also have more Glaucous-like
> migratory behaviour and are less likely to move south.
Well, pale Herring Gulls can be seen in Finland in July. However, they
seem to be more common in winter time, at the same time glaucous and
true hybrids tend to be more common too, that is when the white sea and
everything east of it all the way to the Bering straights freeze.
Harry
_____________________________________________________________________
Dr. Harry J Lehto Assistant Professor, Docent
Tuorla Observatory Yliassistentti, Dosentti
Turku University Tel: +358-2-2744263
Väisäläntie 20 Fax: +358-2-2433767
21500 Piikkiö, FINLAND email: hlehto(AT)utu.fi
______________________________________________________________________
[ << | >> | ^^ ]
Subject: Re: Argentatus vs. hyperboreus: hybrid or not ?
From: Peter Adriaens <peter.adriaens(AT)dutchbirding.nl>
Date: 18 Dec 2003 1:06pm
Hi Dick,
I can see what you mean. However:
>>
> If one first considers Kumlien's Gull it is notable that it is more
> variable
> than supposed "pure" species. Although it is now generally accepted that
> it
> is a mixture of Iceland and Thayer's Gulls, the majority of them are more
> similar to Iceland Gull than they are to Thayer's in both plumage and
> structure.
>
Not sure if I agree with you there, but let's not get into this for now...
> These supposed Glaucous x Herring types are certainly very variable, from
> those with very obvious Glaucous Gull influence to those which look more
> like Herring Gulls (the majority).
>
Do you have any references or evidence that the majority of such hybrids
would look more like Herring Gulls? As far as I know, this is not the case
in Iceland (cf. the articles by Ingolfsson)! Let us stick to the evidence
and look at the situation on the breeding grounds first, rather than make
assumptions on the basis of birds of uncertain identity.
> Why should most of them look more like one species than the other? This
> could simply be because the introgression of A into B will produce more
> B-type offspring than the other way round because further crosses are more
> likely to be with B and so B-type appearance will dominate.
> Further, in the case of Glaucous x Herring hybrids, it could well be that
> the ones that look more like Glaucous Gulls also have more Glaucous-like
> migratory behaviour and are less likely to move south.
>
While this is entirely possible, it is only a theory. Note your use of the
words "should", "could", and "likely".
If you take into account that pale Herring Gulls do exist (and are
regular), there is little reason to identify so many 'pale herring gull
types' as hybrids. Where and how exactly would you draw the line?
If you remember, you and I saw a few very pale, fresh juvenile Herring
Gulls in southern Finland in early August of last year, far away from any
Glaucous Gulls.
What would you call such birds if they were to turn up on your local patch
(out of context) a few months later, in a more worn and even paler state
of plumage?
Wishing you a white-winged Christmas,
Peter
[ << | >> | ^^ ]
Subject: Re: Argentatus vs. hyperboreus: hybrid or not ?
From: Tim Vaughan <timvaughan(AT)TALK21.COM>
Date: 18 Dec 2003 2:17pm
Hi,
I agree that this Herring Gull is more likely to be a variation within
L.a.argentatus rather than a hybrid HGull x Glaucous. Over the past decade
occasional birds like this have been seen in winter in NW England and each time
I am not convinced that they show enough features that aren't within the
massive range shown by Herring Gulls. In fact In have never knowingly seen a
hybrid...but then maybe I have ?.......
Best wishes,
Tim Vaughan
Seaforth, UK
--------------------
talk21 your FREE portable and private address on the net at
http://www.talk21.com
[ << | >> | ^^ ]
Subject: Re: Pacific Golden-Plover in Barbados?
From: julian hough <jrhough1(AT)SNET.NET>
Date: 18 Dec 2003 5:52pm
The pictures on Floyd's page look like fulva, with a nice yellow-buff
flush to the face, conspicuous yellow notches to the upperparts, longish
bill, contrastingly whitish belly (often seen on juv/1st cal fulva, as
opposed to dominica), short primary projection, and from what can be
seen of the legs, they look like they are long.
(Of course, if he posts the summer-plumaged photos and it's a full-blown
dominica, I'll look rather foolish...)
Here's hoping for barred, white flank stripes......
Julian Hough,
CT, USA
[ << | >> | ^^ ]
Subject: Re: the NZ GP
From: matt kenne <mkenne(AT)NETAMUMAIL.COM>
Date: 18 Dec 2003 10:53pm
Chris wrote:
> If you look at Howell et al 2003 (Condor, 105, part 4: 635 - 653), it
> suggests that the Pluvialis plovers might have a Simple Alternate
Strategy,
> citing a paper by Howell and Pyle (2002, Western Birds, 33:268-270). If
> true, this would mean that the first post-juvenal molt would be the molt
> which produces 1st Alternate plumage. If this was such a case, then it
could
> be that the eyebrows have already molted into new, 1st Alternate feathers.
> Hence white.
I think it's just too soon (or too late) for the white eyebrow to result
from 1st alternate plumage. From Oscar and Patricia Johnson's field work on
wintering PAGP in Hawaii (Condor 85:406-419):
Under prealternate molt- "As briefly mentioned in Figure 1, the first
indications of prealternate molting were seen in late January. They
consisted of slightly brighter coloration on the back and crown combined
with faint suggestions of the incoming supercilliary and neck stripes."
Under prebasic molt- "As the prebasic molt of adults neared completion, the
feathering of the head and neck provided the last evidence of earlier
breeding coloration. Although the white feathers of the supercilliary line
and neck stripe were replaced by buffy feathers, the latter continued to
produce a pattern that was discernable for several weeks. With time, this
pattern faded and by early December relatively little of it remained. At
this point, the basic body plumages of adults and juveniles were essentially
identical and the two groups could not be distinguished unless the birds
were in the hand."
> Whatever, I think the most important point is that the stark white
> supercilium in no way argues against the bird being a PAGP. And I argue
that
> the grey breast feathers are also not a good argument either way. We have
to
> be careful not to read too much into features which apply best to birds in
> fresh juvenal plumage, since this isn't a bird in fresh, juvenal plumage.
I agree that this bird shouldn't be judged by juvenal standards- by the
mid/end of November, the bird should be in new basic plumage with few worn
juvenal body feathers remaining. Almost 100% of Johnsons' Hawaii birds were
visually determined to be in "basic" plumage by late Nov, but granted, they
weren't searching for retained juvenal plumage- they were just looking for
retained alternate plumage and leaving the aging of basic-plumage birds to
in-hand checks of primary wear. The bird behind the mystery bird is what I
think an adult PAGP almost molted into basic plumage from black/white/and
gold breeding plumage should look like at the mid/end of Nov- even including
a couple of retained blackish feathers in the breast/belly. Given the major
difference in appearance between the two, I don't think the plover in
question came from the same plumage starting point as the one in back. I
think either: (1) The bird is mostly in 1st basic, which accounts for some
fresh, gold-spotted scaps along with the retained worn, faded, and pointy
scaps that I see. The exposed coverts look faded enough to be retained juv
coverts awaiting new 1st-basic overlays. There is no problem with molting
primaries affecting perceptions, because PAGP don't lose primaries until
their second fall/winter. Or, (2) The bird never achieved black-and-white
alternate breeding plumage or migrated north. It summered in NZ, fading the
1st basic plumage and whatever basic-looking "alternate" plumage it got. A
regular portion of 1-year old birds follow this strategy before heading
north the following year. There might be a problem with molted primaries
because "summering" birds start primary molt early (July), with molt
completing by the end of Nov. Molt timing doesn't agree with this option,
though, because the faded "summering" plumage should be mostly changed to
regular 2nd-basic by Nov 21. Maybe if David James still subscribes to this
list he could offer us his viewpoint from Down Under?
Happy Holidays!
Matthew Kenne
Algona, Iowa
mkenne(AT)netamumail.com
[ << | >> | ^^ ]
Subject: Easton's 'Mystery Gull'---again!
From: Dave DeReamus <becard(AT)FAST.NET>
Date: 19 Dec 2003 1:28am
Hi all,
You may remember (or might want to forget) my posting about a "dark-mantled,
yellow-legged" gull that was found in Easton, PA back in the fall of 2000.
I got many great responses and the general consensus seemed to be that it
was most likely an aberrant Herring Gull, possibly of the subspecies
'argentatus'. Well, I found it again on December 11th and 12th and managed
to get a few more photos of it. They're not the best, but if anyone would
like to take a look at them, along with the others from back in 2000, they
can be directly accessed at the following address on my Website:
http://www.users.fast.net/~becard/index8.html
Any additional comments or suggestions on this 4-year long mystery would be
greatly appreciated.
Happy Holidays and Good Birding,
Dave DeReamus
Compiler of the 'Eastern PA Birdline'
Easton, PA
becard(AT)fast.net
Eastern PA Birding Website: http://www.users.fast.net/~becard/index.html
[ << | >> | ^^ ]
Subject: Re: Argentatus vs. hyperboreus: hybrid or not ?
From: Dick Newell <dick.newell(AT)MACUNLIMITED.NET>
Date: 19 Dec 2003 3:32am
Hi Peter
[first - can the list moderator tell us if we should take this discussion
private?]
***I'll try and answer your points with lines like this.
I have no proof of what I am saying, so I may be wrong - but I am trying to
draw inferences from what I see - which is incomplete information. The 2
alternative theories need testing either by DNA or someone taking a good
look at birds on the breeding grounds to see what they look like, and to see
what is the incidence of hybrid pairs.
On 18/12/03 8:06 pm, "Peter Adriaens" <peter.adriaens(AT)DUTCHBIRDING.NL>
wrote:
> Hi Dick,
> I can see what you mean. However:
>
>>>
>> If one first considers Kumlien's Gull it is notable that it is more
>> variable
>> than supposed "pure" species. Although it is now generally accepted that
>> it
>> is a mixture of Iceland and Thayer's Gulls, the majority of them are more
>> similar to Iceland Gull than they are to Thayer's in both plumage and
>> structure.
>>
>
> Not sure if I agree with you there, but let's not get into this for now...
***I wouldn't want to get into an argument about this either! The point is
based on my experiences in California, Niagara and the East coast
>
>
>> These supposed Glaucous x Herring types are certainly very variable, from
>> those with very obvious Glaucous Gull influence to those which look more
>> like Herring Gulls (the majority).
>>
>
> Do you have any references or evidence that the majority of such hybrids
> would look more like Herring Gulls?
***we all seem to agree that the majority (not all) of these birds look more
like Herring Gulls than Glaucous Gulls and I previously proposed a theory to
explain why this might be (actually 2 theories!). No I don't have a
reference.
> As far as I know, this is not the case
> in Iceland (cf. the articles by Ingolfsson)! Let us stick to the evidence
> and look at the situation on the breeding grounds first, rather than make
> assumptions on the basis of birds of uncertain identity.
***Of course one must include generations of hybrid beyond the first and
maybe one should look at Mendelian implications. In Iceland, is it not more
a case of a hybrid zone than a case of introgression of one species into
another? I don't have the Ingolfsson articles. The answer to this question
really depends on the dynamics of the 2 populations, and also, what we see
in the south depends on the migration strategies of the 2 species. The
situation up there in Finnmark (or wherever) is almost certainly different
from the situation in Iceland. (that's a point - are we agreed on where
these birds might be coming from? - does anyone have a supported theory
about this?)
>
>
>> Why should most of them look more like one species than the other? This
>> could simply be because the introgression of A into B will produce more
>> B-type offspring than the other way round because further crosses are more
>> likely to be with B and so B-type appearance will dominate.
>> Further, in the case of Glaucous x Herring hybrids, it could well be that
>> the ones that look more like Glaucous Gulls also have more Glaucous-like
>> migratory behaviour and are less likely to move south.
>>
>
> While this is entirely possible, it is only a theory. Note your use of the
> words "should", "could", and "likely".
***oh absolutely it's only a theory, and so is your explanation "only" a
theory. I (and one or two other people) once had a theory that a funny skua
that turned up injured in the Scilly Isles was not a Bonxie (many informed
people were saying it was just a Bonxie) - and (unusually) I was right!
>
> If you take into account that pale Herring Gulls do exist (and are
> regular), there is little reason to identify so many 'pale herring gull
> types' as hybrids. Where and how exactly would you draw the line?
> If you remember, you and I saw a few very pale, fresh juvenile Herring
> Gulls in southern Finland in early August of last year, far away from any
> Glaucous Gulls.
> What would you call such birds if they were to turn up on your local patch
> (out of context) a few months later, in a more worn and even paler state
> of plumage?
***what I would call them would depend on how many traits of Glaucous I
could pick out. Glaucous-type traits would be a very obvious broken
eye-ring, obvious dark sub-terminal chevrons in the primaries, frilly
scapulars would be supportive, as would translucent primaries, lack of a
tail-band, a Glaucous-like head-shape and so on - I wouldn't class all pale
Herring Gulls as hybrids. e.g. I am not a supporter of the Italian gull as a
hybrid, but it may be, it's a "don't know" in my book.
>
> Wishing you a white-winged Christmas,
*** I am all for that!
Dick
> Peter
>
[ << | >> | ^^ ]
Subject: Re: Argentatus vs. hyperboreus: hybrid or not ?
From: Millington/BIS <sales(AT)birdingworld.co.uk>
Date: 19 Dec 2003 4:02am
Hi Dick and Peter and moderator,
Please don't take this discussion private.
I've been following it with great interest (but saying nothing)
I'm sure there are others like me.
If it is deemed unsuitable for this chat group,
maybe slip it across to a currently quiet one like Surfbirdnews
If you go somewhere else with it, please link us there
cheers
Richard
_____________________________
----- Original Message -----
From: "Dick Newell" <dick.newell(AT)MACUNLIMITED.NET>
Sent: 19 December 2003 10:33
Subject: Re: [BIRDWG01] Argentatus vs. hyperboreus: hybrid or not ?
> Hi Peter
> [first - can the list moderator tell us if we should take this discussion
> private?]
[ << | >> | ^^ ]
Subject: Re: Argentatus vs. hyperboreus: hybrid or not ?
From: Matt Sharp <sharp(AT)ACNATSCI.ORG>
Date: 19 Dec 2003 8:11am
With sympathies to all who find gull discussion
tedious I just want to second Richards request
to keep this thread public.
Happy Holidays
Matt
>>> Millington/BIS <sales(AT)BIRDINGWORLD.CO.UK> 12/19/03 06:01AM >>>
Hi Dick and Peter and moderator,
Please don't take this discussion private.
I've been following it with great interest (but saying nothing)
I'm sure there are others like me.
If it is deemed unsuitable for this chat group,
maybe slip it across to a currently quiet one like Surfbirdnews
If you go somewhere else with it, please link us there
cheers
Richard
[ << | >> | ^^ ]
Subject: Re: Argentatus vs. hyperboreus: hybrid or not ?
From: Peter Adriaens <peter.adriaens(AT)dutchbirding.nl>
Date: 19 Dec 2003 8:21am
> I have no proof of what I am saying, so I may be wrong - but I am trying
> to
> draw inferences from what I see
>
Ok, but what you see, are birds (far) away from the breeding grounds, out
of their normal context, right? If we really want to learn new facts about
them, this is not a good starting point.
> ***we all seem to agree that the majority (not all) of these birds look
> more
> like Herring Gulls than Glaucous Gulls
>
No! The point is that we give a different meaning to "these birds". In my
view, they are Herring Gulls, and that is why they are so similar to
Herring Gull... In your opinion, they are hybrids (backcrosses?) that are
similar to Herring Gull.
> ***Of course one must include generations of hybrid beyond the first and
> maybe one should look at Mendelian implications. In Iceland, is it not
> more
> a case of a hybrid zone than a case of introgression of one species into
> another?
>
Well, yes. A restricted hybrid zone makes more sense anyway, since
Glaucous and European Herring Gull are different species. The number of
mixed pairs is even said to be declining these days (any Icelandic birders
on this list who can confirm this?).
Do you think Glaucous and European Herring Gull are that closely related
to allow for widespread gene introgression of the one species into the
other?
> The answer to this question
> really depends on the dynamics of the 2 populations, and also, what we see
> in the south depends on the migration strategies of the 2 species. The
> situation up there in Finnmark (or wherever) is almost certainly different
> from the situation in Iceland. (that's a point - are we agreed on where
> these birds might be coming from? - does anyone have a supported theory
> about this?)
>>
Again, as far as I know, there is still no evidence of interbreeding of
the two species in Finmark. In addition, if there is a hybrid zone up
there (which is possible, of course), why would the situation be very
different from the one in Iceland? They are still the same two species!
Since you mention migration strategies: from ringing recoveries, we know
that Herring Gulls from Finmark reach western Europe (Belgium,
Britain,...) in winter. As some of these northern Herring Gulls can be
very pale, the occurrence of pale northern Herring Gulls in western Europe
in winter is easily explained.
Peter
[ << | >> | ^^ ]
Subject: RE : Argentatus vs. hyperboreus:
hybrid or not ?
From: =?iso-8859-1?Q?Pierre-Andr=E9_CROCHET?= <crochet(AT)CEFE.CNRS-MOP.FR>
Date: 19 Dec 2003 8:53am
Well, wince some people seem to be interested in this topic (sorry ot the
others), I thought I might say something, since Dick (salut Dick!) quoted "my"
work and Peter (salut Peter!) said some things I can't agree totally with.
I think the first point to settle is that we can't answer the question of
whether the pale Herring gulls are "intergrades" or part of the normal variation
of Herring Gull with the available data. The second point to settle is that
this question is somewhat academic: there is apparently enough gene flow among
large gulls so that part of the variation of one species can be explained by
past introgression with other species.
First, hybrids or intergrades? There seems to be a few undisputed hybrids
Herring X Glaucous (I mean one parent is Herring and one is Glaucous) out there
(in Europe). These birds have really intermediate characters, as can be expected
for a F1 progeny. I think we can all agree that the "pale Herring" that are
being discussed here are not F1 hybrids (or at least that most are not), for the
reasons developed by Peter.
Second, are they part of the variation of pure Herring (as Peter seems to
believe) or do they result from introgression between Herring and Glaucous?
That's the difficult part. I'm convinced that its possible that these birds are
intergrades. There is enough hybridisation going out to make this possible. The
fact that these birds come from NW Siberia or NE Finmark does not bother me.
Glaucous and Herring come very close together there (if not actually together),
and hybrids are mostly the results of out of range birds (see YLG hybrids in
Holland...). So, nothing that we know of these birds allows us to dismiss the
possibility that these pale Herring are intergrades. I have a sample of Glaucous
Gull from W Siberia with an haplotypes that is common in Scandinavian Herring
Gull (see Auk paper). This is no prove of current hybridization, but indicates
that exchange of genetic material between Glaucous and Herring in this region is
likely.
How to test the intergradation theory? Well, if these pale birds are just pale
Herring, they should be typical Herring for other genes. You should not see any
difference between these birds and typical Herring from the same populations
when you look at microsatellites, because there is NO reason to expect that
microsatellites and plumage traits are linked (I mean physically linked, ie
close in the genome). On the other hand, if they are intergrades, they should
have inherited not only these plumage traits, but also other genes, and in
microsatellites they should be somehow similar to Glaucous. To be technical,
there should be no linkage disequilibrium between microsatellites and plumage
traits if they are "pure" Herring, but there should be some if they are
intergrades.
Theoretically, the answer is thus very simple: take feather or blood samples
from these pale Herring, and compare their multilocus genotype (based on, say,
15-20 microsatellites) with genotypes of standart looking Herring and Glaucous.
Technically, we still don't have that many microsatellite loci working on large
gulls (that should not take more than 1-2 years to solve) and we still have not
enough samples of Glaucous Gull available to do the analyses. This could be a
bit longer to solve...
Anyway, it might be a good idea to try to sample any pale Herring that you come
across.
Hope this has been if interest to somebody...
Best,
Pierre
Pierre-André Crochet
CEFE-CNRS
1919, route de Mende
34293 Montpellier cedex 5
France
tel: + 33 6 07 32 60 75
fax: + 33 4 67 41 21 38
crochet(AT)cefe.cnrs-mop.fr
-----Message d'origine-----
De : NBHC ID-FRONTIERS Frontiers of Field Identification
[mailto:BIRDWG01(AT)LISTSERV.ARIZONA.EDU] De la part de Peter Adriaens
Envoyé : vendredi 19 décembre 2003 16:22
À : BIRDWG01(AT)LISTSERV.ARIZONA.EDU
Objet : Re: [BIRDWG01] Argentatus vs. hyperboreus: hybrid or not ?
> I have no proof of what I am saying, so I may be wrong - but I am trying
> to
> draw inferences from what I see
>
Ok, but what you see, are birds (far) away from the breeding grounds, out
of their normal context, right? If we really want to learn new facts about
them, this is not a good starting point.
> ***we all seem to agree that the majority (not all) of these birds look
> more
> like Herring Gulls than Glaucous Gulls
>
No! The point is that we give a different meaning to "these birds". In my
view, they are Herring Gulls, and that is why they are so similar to
Herring Gull... In your opinion, they are hybrids (backcrosses?) that are
similar to Herring Gull.
> ***Of course one must include generations of hybrid beyond the first and
> maybe one should look at Mendelian implications. In Iceland, is it not
> more
> a case of a hybrid zone than a case of introgression of one species into
> another?
>
Well, yes. A restricted hybrid zone makes more sense anyway, since
Glaucous and European Herring Gull are different species. The number of
mixed pairs is even said to be declining these days (any Icelandic birders
on this list who can confirm this?).
Do you think Glaucous and European Herring Gull are that closely related
to allow for widespread gene introgression of the one species into the
other?
> The answer to this question
> really depends on the dynamics of the 2 populations, and also, what we see
> in the south depends on the migration strategies of the 2 species. The
> situation up there in Finnmark (or wherever) is almost certainly different
> from the situation in Iceland. (that's a point - are we agreed on where
> these birds might be coming from? - does anyone have a supported theory
> about this?)
>>
Again, as far as I know, there is still no evidence of interbreeding of
the two species in Finmark. In addition, if there is a hybrid zone up
there (which is possible, of course), why would the situation be very
different from the one in Iceland? They are still the same two species!
Since you mention migration strategies: from ringing recoveries, we know
that Herring Gulls from Finmark reach western Europe (Belgium,
Britain,...) in winter. As some of these northern Herring Gulls can be
very pale, the occurrence of pale northern Herring Gulls in western Europe
in winter is easily explained.
Peter
--
passerelle antivirus du campus CNRS de Montpellier
--
--
passerelle antivirus du campus CNRS de Montpellier
--
[ << | >> | ^^ ]
Subject: Re: RE : Argentatus vs. hyperboreus:
hybrid or not ?
From: Peter Adriaens <peter.adriaens(AT)dutchbirding.nl>
Date: 19 Dec 2003 10:06am
Salut Pierre-André,
>
> I think the first point to settle is that we can't answer the question of
> whether the pale Herring gulls are "intergrades" or part of the normal
> variation of Herring Gull with the available data.
>
This implies that you cannot call such birds hybrids with any confidence,
which is what I wanted to point out.
> I think we can all agree that the "pale
> Herring" that are being discussed here are not F1 hybrids (or at least
> that most are not),
>
And that is really all I wanted to say!
I am no taxonomist, so I certainly don't know if and when introgression
with Glaucous Gull has been going on. However, I do not buy the hypothesis
that paleness of the wingtips alone would be enough to indicate any
Glaucous Gull influence, at least not in Europe. It cannot be that simple.
Large gulls are not that simple.
> Second, are they part of the variation of pure Herring (as Peter seems to
> believe) or do they result from introgression between Herring and
> Glaucous?
> That's the difficult part.
>
Very difficult! Even when you would prove that some 'pale herring gull
types' from a certain region (let's say NE Finmark) have Glaucous Gull
haplotypes, that still would not mean that birds from other regions, such
as southern Finland, have the same genetic influence too. So you would
need to look at significant numbers of pale birds from many different
regions.
> I'm convinced that its possible that these
> birds are intergrades.
>
I certainly believe that some of them are (and that some may even be F1
hybrids), but all of them? My guess is that both occur: intergrades (with
Glaucous Gull influence from I-don't-know-how-many generations ago), and
pale extremes of (pure) Herring Gulls.
>
> Anyway, it might be a good idea to try to sample any pale Herring that you
> come across.
>
Promised!
Peter
[ << | >> | ^^ ]
Subject: Fw: another Golden Plover identification
discussion
From: matt kenne <mkenne(AT)NETAMUMAIL.COM>
Date: 19 Dec 2003 4:22pm
Here's a note from Oscar Johnson.
Matthew Kenne
Algona, Iowa
mkenne(AT)netamumail.com
----- Original Message -----
From: <OWJohnson2105(AT)aol.com>
To: <mkenne(AT)netamumail.com>
Cc: <silcock(AT)rosssilcock.com>; <upupa(AT)airmail.net>;
<redwingatfp1986(AT)comcast.net>; <corben(AT)hoarybat.com>; <dpaulson(AT)ups.edu>
Sent: Friday, December 19, 2003 12:52 PM
Subject: Re: another Golden Plover identification discussion
> Greetings Matthew,
>
> Thanks for sending along the ID commentary from various people.
> Golden-Plovers in the Bay of Plenty bring back fond memories as my wife
and I saw them
> there along with a number of other species in March '01. Discussion
concerning
> the NZ bird comes at an opportune time as we recently completed a rather
> extensive manuscript on morphometrics in PAGPs and AMGPs. We have lots of
data from
> banding over the years, and gave special attention to interspecific
criteria
> the past couple of seasons in Hawaii and Alaska. The paper will appear
next
> spring in the journal Wader Study Group Bulletin. I'll refer to some of
our
> findings in what follows.
>
> First of all, I don't think there's any question that the bird, though
> unusually grayish, is a PAGP. This variation has been noted by others,
and a color
> photograph of a Pacific which is essentially identical to the NZ bird
appears
> in Golley & Stoddart (Birding World 4: 195-204, 1991, Plate 13).
>
> We've examined in some detail the bill/eye relationship put forth by
> Byrkjedal and Thompson. According to B&T, rearward projection of the bill
"reaches
> well beyond the eye in Pacific, but barely across the eye in American".
We
> found this to be generally true, but there were exceptional individuals in
both
> species (shorter-billed Pacific and longer-billed American). To make
these
> measurements, we followed a straight line from the tip of the bill across
the
> nasal opening (i.e., the line runs slightly lateral to the culmen). When
I
> approximate this on image #1, it is clear that the bill does indeed go
"well beyond
> the eye" -- I estimate at least 5 mm. This falls outside the range of
> interspecific overlap we measured and places this individual solidly among
typical
> PAGPs.
>
> Some of the comments you forwarded have to do with tertial length relative
to
> the tail. Quoting Byrkjedal and Thompson, "the tip of the longest tertial
> ends just beyond the tail basis in the American, but over the outer third
of the
> tail in the Pacific". As with the bill/eye relationship, this difference
> often holds up, but there's much variation and we have photos of both
species in
> breeding plumage (no molt, tertials fully grown) with the tertial/tail
> relationship reversed from what B&T describe. In fact, note the photos on
the cover
> page of the BNA monograph (Johnson and Connors 1996) where relatively
short
> tertials are obvious on the Pacific and with a magnifying glass one can
see long
> tertials on the American. Bottom-line, the tertial/tail relationship can
be
> a helpful ID feature, but it can also be misleading.
>
> The same applies to a couple of other features mentioned by B&T --
distance
> between tips of primaries 9 &10, and length of tibia. Lots of variation
and
> interspecific overlap. Aside from breeding plumage, the only field
criteria
> that we found to be reasonably accurate were number of primary tips beyond
the
> tertials (2-3 Pacific, 4-5 American), and projection of the primaries past
the
> end of the tail (0-9 mm Pacific, 12-22 American). Unfortunately, my
computer
> is not showing clearly defined primary tips on the NZ photos, and given
the
> angle from which the pictures were taken it's not possible to accurately
estimate
> projection past the tail. Nonetheless, what I do see looks OK for
Pacific.
> Notably, primary projection appears to be identical on both birds in the
> photos as viewed from the same angle.
>
> The fine patterning on the breast plus what appears to be barring on the
> posterior flank immediately say juvenile to me. From the late November
time
> frame, this is an individual probably in early stages of postjuvenal
(prebasic I)
> body molt. Note the contrast in breast feathering between the two birds.
The
> smudgy effect on the left hand plover is very characteristic of an adult
in
> postbreeding (prebasic) molt.
>
> Happy Holidays, Wally
>
> Dr. Oscar W. Johnson
> Department of Ecology
> Montana State University
> Bozeman, MT 59717
> tel: 406-587-7305
> e-mail: owjohnson2105(AT)aol.com
>
[ << | >> | ^^ ]
Subject: More images of the Delaware plover
From: Anthony Gonzon <FlyersFan074(AT)AOL.COM>
Date: 19 Dec 2003 4:42pm
----INCLUDING text/plain MIME SECTION----
I have posted a few images of the Delaware bird on my site. The images can
be found at:
http://www.geocities.com/anthony_t_gonzon/plover.html
Any comments are welcome.
Anthony T. Gonzon, Jr.
Middletown, DE
flyersfan074(AT)aol.com
http://www.geocities.com/anthony_t_gonzon/home.html
----DELETED text/html MIME SECTION----
[ << | >> | ^^ ]
Subject: Re: Argentatus vs. hyperboreus: hybrid or not ?
From: Bruce Mactavish <bruce.mactavish1(AT)NF.SYMPATICO.CA>
Date: 19 Dec 2003 8:06pm
“no linkage disequilibrium between microsatellites and plumage traits if
they are "pure"” said Pierre-André Crochet
Thank God Herring Gulls and Glaucous Gulls don’t about know this!
I have long been fascinated by the difference between 1st winter gulls
identified as hybrid Glaucous Gull (GLGU) x Herring Gull (HEGU) in the
various European birding journals and on the Net versus the same hybrid
combination I see in Newfoundland (and occurs elsewhere in northeast
North America) Hybrid GLGUxHEGU in Newfoundland are typically very much
like Glaucous Gulls including bill pattern and over all paleness but
have solid medium brown wash on outer primaries, tertials and a faded
smithsonianus-like tail pattern. Typical gulls identified as GLGUxHEGU
in Europe are more like Herring Gulls dipped in flour with pale outer
primaries, argentatus-like tail band, pale broad fringed wing coverts
and scapulars, paler upperparts and a usually a dark Herring Gull-like
bill. In the last 15 years I can remember only one 1st winter gull in
Newfoundland that bore a resemblance to the typical hybrid European
GLGUxHEGU (or extremely pale argentatus Herring Gull) but I see several
classic 1st winter northeast North American GLGUxHEGU annually.
It is interesting to follow the discussion on ID Frontiers on whether
these are pale northern argentatus Herring Gulls or hybrid HEGUxGLGU or
some of each. I am not participating in that argument but would like to
point out that different populations of GLGU and HEGU can produce
different looking hybrids.
As I already pointed out typical northeast North America 1st winter
GLGUxHEGU are like Glaucous Gulls with some Herring Gull features. I
spent two summers based in Inuvik, Northwest Territories, Canada. This
town is adjacent to Yukon and 40 km inland from the Beaufort Sea.
Herring Gulls reach a northern breeding limit around Inuvik and overlap
with the Glaucous Gull, very common breeding along the coast. A minimum
5% of the gulls at the Inuvik dump were hybrid GLGUxHEGU. But rarely
were the hybrids like the ones I was familiar with in Newfoundland. The
adults had more extensive but grayer wing tip patterns and the subabults
were highly variable covering a range from odd Herring Gull-like birds
to odd Glaucous Gull-like birds. Juveniles seen in mid August to mid
September could look be like a GLGU heavily marked on wing coverts,
scapulars, dense wash of brown on body, solid brown outer primaries and
GLGU-like bill but with dirty pink base and poorly defined black tip. Or
could look like a pale smithsonianus Herring Gull with low contrast
between tertials and folded primaries and rest of upper parts. Or like
nominate Iceland Gull but too robust, black bill, coarsely marked wing
coverts and scapulars and dirty wash on outer primaries.
The Inuvik Glaucous Gulls were probably barrovianus or at least more
closely affiliated with barrovianus then hyperboreus. To my eye
averaging smaller and darker above than the large pale hyperboreus birds
I was used to in winter in Newfoundland. Also darker yellow iris (some
with dark flecking) and redder orbital ring. The Inuvik Herring Gulls,
although not recognized as a different subspecies from Newfoundland
birds, seemed smaller, more compact, distinctly more black in wing tip,
probably slightly darker above, iris with greater tendency to contain
dark speckles.
Glaucous Gulls and Herring Gulls in northwest and northeast Canada
produce different looking hybrids. It seems likely that the hyperboreus
Glaucous Gull (adults with more heavily streaked head in winter than
eastern North American birds) and an argentatus Herring Gull in northern
Europe would produce yet another version - conceivably looking like
argentatus dipped in flour.
Bruce Mactavish
St. John's, Newfoundland
Canada
bruce.mactavish1(AT)nf.sympatico.ca
[ << | >> | ^^ ]
Subject: more on mystery nightjar from E Chiapas
From: Vladimir Dinets <v0v04ka(AT)HOTMAIL.COM>
Date: 20 Dec 2003 2:15am
Dear All,
I recieved very few replies concerning the ID of the bird. All 3 respondents
suggested buff-collared nightjar. I found a few more pictures of that
species, and indeed, they are very similar to my mystery bird, with two
differences: the one I videotaped has no buff collar, and has striking b&w
pattern on the scapulars.
Could it be C. r. troglodytes, the Central American subspecies? HBW states that
it has "scapulars more boldly spotted cinnamon and gray". It
also shows a gap in the species' range in Chiapas. If my bird is of this
subspecies, it would be the first record for Mexico, and an indication that
there might actually be no such gap.
I'd appreciate any comments, especially from people who have seen C. ridgwayi
troglodytes or its photos.
The video stills of the mystery nightjar can be seen at:
http://dinets.travel.ru/mexnightjar1.jpg
http://dinets.travel.ru/mexnightjar2.jpg
[ << | >> | ^^ ]
Subject: Re: Argentatus vs. hyperboreus: hybrid or not ?
From: Dick Newell <dick.newell(AT)MACUNLIMITED.NET>
Date: 20 Dec 2003 3:23am
On 20/12/03 3:06 am, "Bruce Mactavish" <bruce.mactavish1(AT)NF.SYMPATICO.CA>
wrote:
> I have long been fascinated by the difference between 1st winter gulls
> identified as hybrid Glaucous Gull (GLGU) x Herring Gull (HEGU) in the
> various European birding journals and on the Net versus the same hybrid
> combination I see in Newfoundland (and occurs elsewhere in northeast
> North America) Hybrid GLGUxHEGU in Newfoundland are typically very much
> like Glaucous Gulls including bill pattern and over all paleness but
> have solid medium brown wash on outer primaries, tertials and a faded
> smithsonianus-like tail pattern. Typical gulls identified as GLGUxHEGU
> in Europe are more like Herring Gulls dipped in flour with pale outer
> primaries, argentatus-like tail band, pale broad fringed wing coverts
> and scapulars, paler upperparts and a usually a dark Herring Gull-like
> bill. In the last 15 years I can remember only one 1st winter gull in
> Newfoundland that bore a resemblance to the typical hybrid European
> GLGUxHEGU (or extremely pale argentatus Herring Gull) but I see several
> classic 1st winter northeast North American GLGUxHEGU annually.
***this is almost to be expected as smithsonianus is closer to hyperboreus
than either are to argentatus and indeed the 1st year birds of hyperboreus
and smith are similar in a number of respects, but one is a lot darker than
the other. It is therefore not surprising, for example, that Nelson's Gull
often has a Glaucous-type bill - it's a trait common to both parents. I have
sometimes wondered whether the occasional chocolate flavoured argentatus,
resembling a smith is the result of Glaucous introgression into argentatus,
the result having the plumage tone of argy and the texture of hyperboreus.
Question: How often do Nelson's Gulls show pale fringed primaries with a
dark sub-terminal spot or chevron? If we ever get proof that these European
birds are hybrids, then I would regard this as a strong criterion for
identifying some of them.
Dick, Cambridge, UK
[ << | >> | ^^ ]
Subject: Variation in Larus thayeri
From: Joseph Morlan <jmorlan(AT)CCSF.ORG>
Date: 20 Dec 2003 9:19pm
If you're not fully saturated with unknowable or mutant gulls, here's a few
more from the West Coast.
I've posted three images of a pale 1st year presumed Thayer's Gull from
Half Moon Bay at:
http://community.webshots.com/album/104073794uAYlcq
The first three shots are of the bird in question with very heavily mottled
tertials. This is a feature I have never seen on thayeri before and is one
thing I look for on Iceland Gull. Is it from introgression or is it within
the range of variation of either Thayer's or Iceland? Is this a bird that
would be claimed as Thayer's if seen in the East?
A more "normal" pale thayeri follows for comparison.
Lastly are two images labeled "Apparent Glaucous Gull," a 2nd year bird
from Golden Gate Park in San Francisco. There has been some thoughtful
speculation that this bird may be a Glaucous X Glaucous-winged Gull with
some good arguments and additional photos at:
http://www.badboybirding.com/GLGUxGWGU_12112003.htm
This hybrid combination is much less often claimed than Herring X Glaucous
perhaps because of its close similarity to Glaucous combined with the
difficulty of knowing the range of variation in each of the presumed
parental species.
--
Joseph Morlan, Pacifica, CA 94044 jmorlan(AT)ccsf.org
California Birding & new rarities http://fog.ccsf.org/~jmorlan/
California Bird Records Committee http://www.wfo-cbrc.org/cbrc/
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