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ID-FRONTIERS for July 1-8, 2000
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Messages are displayed in the order they were received.
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| Subject | From | Date | Time |
| European seabird records | Ned Brinkley | Sat, 1 Jul 2000 | 6:40am |
| dunlin vs. curlew sandpiper revisited | Paul Conover | Thu, 6 Jul 2000 | 7:43am |
| Re: dunlin vs. curlew sandpiper revisited | Adriaens, Peter | Thu, 6 Jul 2000 | 8:10am |
| Dunlin vs. Curlew: Another view | Swmavocet(AT)AOL.COM | Thu, 6 Jul 2000 | 7:31pm |
| Dunlin vs. Curlew Sandpiper...... | Angus Wilson | Thu, 6 Jul 2000 | 9:26pm |
| Dunlin/Curlew Sandpiper wingprojection | Koen Verbanck | Fri, 7 Jul 2000 | 6:40am |
| Variability of Curlew SP Bill | James H. Barton | Fri, 7 Jul 2000 | 9:57am |
| birdsong guides | James Bouldin | Fri, 7 Jul 2000 | 1:42pm |
| Re: birdsong guides | Steve Sosensky | Fri, 7 Jul 2000 | 2:23pm |
| Re: birdsong guides | Bill Principe | Fri, 7 Jul 2000 | 2:21pm |
| Dunlin/Curlew Sandpiper wingprojection | DJLauten and KACaste | Fri, 7 Jul 2000 | 6:55pm |
| Ontario Slaty-backed Gull | Robert H. Lewis | Fri, 7 Jul 2000 | 9:06pm |
| dunlin vs. curlew sandpiper | Paul Conover | Sat, 8 Jul 2000 | 7:48am |
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[ << | >> | ^^ ]
Subject: European seabird records
From: Ned Brinkley <Phoebetria(AT)AOL.COM>
Date: 1 Jul 2000 6:40am
In the past week, I’ve gotten extremely helpful notes from Europe on the
current status of records of several seabird vagrants -- from Italy (Ottavio
Janni) and Belgium (Gunter de Smet). I attach their correspondence below.
Though only marginally related to identification, I think they will be of
interest to ID-Frontiers’ subscribers.
Gunter de Smet (Chair of the BAHC) writes: “The evidence for Wandering
Albatross in Belgium is extremely poor. The bird in September 1833 near
Antwerpen (Antwerpen) was first reported as second hand information by Boïe,
who was informed by Drapiez. It was first published in Isis, 1835:259. There
is no description of the bird, and no specimen has been preserved. The
identification of the bird killed on 27 April 1887 at Blankenberge
(West-Vlaanderen) could not be confirmed by ornithologists at the time
(Dubois A., Ornis VI, 1890:343). The bird was reportedly killed with a stick,
and eaten by a light house worker. When Dubois inquired if any part of the
bird had been preserved, the keeper of the lighthouse told that "rats or a
cat had probably carried away the head of the albatross, and that nothing
remained." A head, allegedly from the 1887 albatross, is still preserved at
the Royal Belgian Institute for Natural Sciences, but should be considered a
fraud, as already pointed out by Dupond (1945). The head was found in the
collection of de Hemptinne. In 1958 a Giant Petrel from this collection was
offered to the Royal Belgian Institute for Natural Sciences, proving that de
Hemptinne owned other seabird specimens from the southern hemisphere. For
obvious reasons, both records have not been accepted by the Belgian Rarities
Committee (BAHC).”
Ottavio Janni sends the following notes:
“Black-footed Albatross: This has not been accepted to the Italian
list as it is thought it may have been ship assisted. The record is
from Nov. 10 1971 from Torre faro in Sicily. This is where the
Straits of Messina are at their narrowest and is somewhat of a
concentration point for migrating seabirds, but lots of large ships
pass through there as well.
Wandering Albatross: Unlike the previous species, this has been
admitted to the Italian list, though there are suspicions of ship
assistance. The specimen was collected off Sicily Oct 4 1957, it
weighed 6800g and had an empty stomach when it was captured. I don't know
the reason why Wandering was accepted and Black-footed rejected.
Southern Giant Petrel: There is an accepted record from Italy, of a
bird at sea between Puglia and Albania on Sept. 2, 1991. I dont know
if this is a sight, specimen, or photographic record.
Elegant Tern: The record from Sicily was not accepted by the Italian
Records Committee, though it was seen by an excellent observer
Cape Petrel: There is one accepted record (from Sicily in Sept.
1964), and in addition another bird was supposed to have been
collected in the Gulf of Salerno (just south of Naples) in 1977, but
the specimen cannot be found.”
I should point out that Bill Bourne’s article on long-distance vagrancy in
tubenoses covers a lot of similar ground and records similar doubts and
frustrations in dealing with such records; the origins of so many of these
birds will never be strictly knowable, of course, as Bourne and others point
out, but there is probably some value in keeping track of them, should
patterns of vagrancy emerge at some point.
Ned Brinkley
Cape Charles, Virginia, USA
[ << | >> | ^^ ]
Subject: dunlin vs. curlew sandpiper revisited
From: Paul Conover <conover(AT)TALSTAR.COM>
Date: 6 Jul 2000 7:43am
I've been somewhat puzzled by the response to the photo of the mystery
sandpiper at Angus Wilson's site:
http://www.best.com/~petrel/BSmallSHorebird.html
On first glance, the bird struck me as a Dunlin, odd only in its
posture.
This didn't seem extraordinary, as the bird was caught in motion, and seems
to have its feathers tightly pressed to its body, possibly against the heat
of a Texas beach in April. Otherwise, the expression and all plumage
features didn't seem any different from the other thousands of basic Dunlin
that spend a good part of the "colder" months along the Gulf Coast. It
basically seemed like the face of a Dunlin frozen on a running body.
I suspected that the photographer was caught in a common situation,
i.e.,
being sure at the time of what he was photographing, and not seeing
anything remarkable about it until he looked at the photo afterwards and
noticed that it looked reminiscent of another species. I don't know if this
bird was ever put on a hotline, or if any other shots were taken of it. If
this bird was submitted to us
as a quiz bird, perhaps there are more diagnostic shots of it on the roll.
If it was submitted just to solicit commentary, I'd have to guess that my
suspicions are correct and that he thought as he was photographing it that
it was a Dunlin.
I was surprised to find that others thought it might be a Curlew
Sandpiper.
Many of the responses are based on the bird's posture, which is
misleading. Motion shots catch views that we rarely see.
Some suggest that the bird's legs are too long for Dunlin. Certainly,
when
Dunlin are preening or resting, they appear very squat, with short tibiae,
but when feeding, especially in muddy fields or hot beaches, they can
appear a bit stork-legged. If anything, this bird looks too short-legged
for a Curlew, which seems contrary given that the bird is stretching out to
move.
Others thought that the bird had too long of a neck for Dunlin.
However,
views can be misleading. The Curlew photos show a bird that seems have no
neck at times, but nobody suggested that it might be a Dunlin. Nor did the
plumpness of the Curlew have anyone calling it a Dunlin.
The fact that the wingtips seem to distance the tail attracted many
comments. Maybe this bird is a Curlew, and maybe this is indisputable
proof, but I have a feeling that it's just a side-effect of the bird being
in motion. Its wings are pressed more tightly to the body. Anyone who's
ever measured a wing knows that a flattened wing can be a great deal longer
than a wing "at rest", and my guess is that this is what we're seeing here.
The supercilium seems perfect in shape for a Dunlin, especially a worn
late-winter one. This droopy, wispy supercilium is a major contributor to
the characteristic facial expression of winter Dunlin. It shows up more
distinctly here because we're dealing with a great, well-focused photo.
My experience with basic Curlew comes strictly from photos, but I have
yet
to see a Curlew face in any photo that looks anything like this. I don't
mean plumage features strictly--I mean the same type of individual
personality that allows us to tell one human from another. Dwelling too
intently on plumage in this regard could well mean missing the forest for
the trees.
The level of focus for the mystery photo allows a great look at the
feathers, as well. The shaft streaking appears fine for Dunlin, especially
the streaking on the median coverts, a few of which are peeking out.
Compare these median coverts with those on the wing-shot at:
http://www.talstar.com/users/conover/dunlin.html
{while you're at it, view the other photos. unfortunately the basic
dunlin
is a bit blurry, but a good comparison shot.}
I don't know what plumage produced these coverts with their broad dark
shaft streak tapering down to the tip, and I don't know if Curlew shows a
similar pattern there, but it would be worthwhile for someone with
specimens at hand to check it out.
All in all, I know that some heavier hitters than me have weighed in on
this topic, many with an opposing view. I can only say that I'm going to
be very surprised if additional photos prove that this is a Curlew. I've
never seen a basic Curlew, but I have seen tens of thousands of Dunlin in
the same geographic region that this photo was taken [and where a Curlew is
a rarity that would stand out], and I'd be floored to find out that Curlew
could look exactly like Dunlin.
P. Conover
Louisiana/Florida
[ << | >> | ^^ ]
Subject: Re: dunlin vs. curlew sandpiper revisited
From: "Adriaens, Peter" <padriaens(AT)C2000.BE>
Date: 6 Jul 2000 8:10am
When viewing other birders' reactions to this photograph over the
last few weeks, I must say I have had very much the same reaction as Paul
expresses here.
There was one person who said to have a photograph of a basic Curlew
Sandpiper that looked exactly like the 'mystery' bird -- I would definitely
be interested in seeing it, and I wonder why it has not been passed on to
someone with a scanner yet, as it would be very relevant in this discussion.
Best regards,
Peter Adriaens
==>-----Original Message-----
==>From: Paul Conover [mailto:conover(AT)TALSTAR.COM]
==>Sent: donderdag 6 juli 2000 17:41
==>To: BIRDWG01(AT)LISTSERV.ARIZONA.EDU
==>Subject: [BIRDWG01] dunlin vs. curlew sandpiper revisited
==>
==>
==> I've been somewhat puzzled by the response to the
==>photo of the mystery
==>sandpiper at Angus Wilson's site:
==>
==>http://www.best.com/~petrel/BSmallSHorebird.html
==>
==>
==> On first glance, the bird struck me as a Dunlin, odd
==>only in its posture.
==>This didn't seem extraordinary, as the bird was caught in
==>motion, and seems
==>to have its feathers tightly pressed to its body, possibly
==>against the heat
==>of a Texas beach in April. Otherwise, the expression and all plumage
==>features didn't seem any different from the other thousands
==>of basic Dunlin
==>that spend a good part of the "colder" months along the Gulf
==>Coast. It
==>basically seemed like the face of a Dunlin frozen on a running body.
==> I suspected that the photographer was caught in a
==>common situation, i.e.,
==>being sure at the time of what he was photographing, and not seeing
==>anything remarkable about it until he looked at the photo
==>afterwards and
==>noticed that it looked reminiscent of another species. I
==>don't know if this
==>bird was ever put on a hotline, or if any other shots were
==>taken of it. If
==>this bird was submitted to us
==>as a quiz bird, perhaps there are more diagnostic shots of
==>it on the roll.
==>If it was submitted just to solicit commentary, I'd have to
==>guess that my
==>suspicions are correct and that he thought as he was
==>photographing it that
==>it was a Dunlin.
==> I was surprised to find that others thought it might
==>be a Curlew
==>Sandpiper.
==> Many of the responses are based on the bird's
==>posture, which is
==>misleading. Motion shots catch views that we rarely see.
==> Some suggest that the bird's legs are too long for
==>Dunlin. Certainly, when
==>Dunlin are preening or resting, they appear very squat, with
==>short tibiae,
==>but when feeding, especially in muddy fields or hot beaches, they can
==>appear a bit stork-legged. If anything, this bird looks too
==>short-legged
==>for a Curlew, which seems contrary given that the bird is
==>stretching out to
==>move.
==> Others thought that the bird had too long of a neck
==>for Dunlin. However,
==>views can be misleading. The Curlew photos show a bird that
==>seems have no
==>neck at times, but nobody suggested that it might be a
==>Dunlin. Nor did the
==>plumpness of the Curlew have anyone calling it a Dunlin.
==> The fact that the wingtips seem to distance the tail
==>attracted many
==>comments. Maybe this bird is a Curlew, and maybe this is indisputable
==>proof, but I have a feeling that it's just a side-effect of
==>the bird being
==>in motion. Its wings are pressed more tightly to the body.
==>Anyone who's
==>ever measured a wing knows that a flattened wing can be a
==>great deal longer
==>than a wing "at rest", and my guess is that this is what
==>we're seeing here.
==>
==> The supercilium seems perfect in shape for a Dunlin,
==>especially a worn
==>late-winter one. This droopy, wispy supercilium is a major
==>contributor to
==>the characteristic facial expression of winter Dunlin. It
==>shows up more
==>distinctly here because we're dealing with a great,
==>well-focused photo.
==> My experience with basic Curlew comes strictly from
==>photos, but I have yet
==>to see a Curlew face in any photo that looks anything like
==>this. I don't
==>mean plumage features strictly--I mean the same type of individual
==>personality that allows us to tell one human from another.
==>Dwelling too
==>intently on plumage in this regard could well mean missing
==>the forest for
==>the trees.
==> The level of focus for the mystery photo allows a
==>great look at the
==>feathers, as well. The shaft streaking appears fine for
==>Dunlin, especially
==>the streaking on the median coverts, a few of which are peeking out.
==>Compare these median coverts with those on the wing-shot at:
==>
==>http://www.talstar.com/users/conover/dunlin.html
==>
==> {while you're at it, view the other photos.
==>unfortunately the basic dunlin
==>is a bit blurry, but a good comparison shot.}
==>
==> I don't know what plumage produced these coverts
==>with their broad dark
==>shaft streak tapering down to the tip, and I don't know if
==>Curlew shows a
==>similar pattern there, but it would be worthwhile for someone with
==>specimens at hand to check it out.
==>
==> All in all, I know that some heavier hitters than me
==>have weighed in on
==>this topic, many with an opposing view. I can only say that
==>I'm going to
==>be very surprised if additional photos prove that this is a
==>Curlew. I've
==>never seen a basic Curlew, but I have seen tens of thousands
==>of Dunlin in
==>the same geographic region that this photo was taken [and
==>where a Curlew is
==>a rarity that would stand out], and I'd be floored to find
==>out that Curlew
==>could look exactly like Dunlin.
==>
==>
==>P. Conover
==>Louisiana/Florida
==>
[ << | >> | ^^ ]
Subject: Dunlin vs. Curlew: Another view
From: Swmavocet(AT)AOL.COM
Date: 6 Jul 2000 7:31pm
Ooops. Just now, while browsing the excellent book America's 100 Most Wanted
Birds (Mlodinow and O'brien, 1996), I happened to come across the picture on
p. 472 (credited to B. Chudleigh/VIREO) labelled "Curlew Sandpiper."
Hmmm. IMHO, my comparison of this photo with the Small bird shows that its
legs appear proportionally shorter than Small's, the bill is less evenly
curved (especially the lower mandible), the breast area is just as dusky, and
the supercilium is as poorly defined if not more so.
Having only seen one alternate pl. female Curlew, I don't have any experience
with basic pl. to draw on. However, these two pictures appear to me to be
nearly identical. Are they both Dunlin?
Maybe one of the authors or the photographer would give permission to scan
this photo so that a direct comparison could be made for those who do not
have the book...
Steve McConnell
Trussville, AL
[ << | >> | ^^ ]
Subject: Dunlin vs. Curlew Sandpiper......
From: Angus Wilson <wilsoa02(AT)ENDEAVOR.MED.NYU.EDU>
Date: 6 Jul 2000 9:26pm
Hopefully the continuing debate on separation of basic-plumage Dunlin from
Curlew Sandpiper has made it clear that this can be a tricky ID. We have heard
conflicting, but seemingly reasonable, opinions from birders in both North
America and Europe and have reached no strong consensus.
Steve McConnell's comments on the photo in "America's 100 Most Wanted Birds"
reinforces this fact. I suspect the photo by B. Chudleigh he refers to, was
taken in New Zealand where Curlew Sandpiper occurs widely in small numbers and
Dunlin is a significant rarity. In the photo, the left wing is drooped forward
slightly revealing predominantly white uppertail coverts, however, we cannot
see
the very center of the white patch to confirm or refute the presence of a dark
central bar.
The somewhat out of focus shorebird in the background looks like a Wrybill
(Anarhynchus frontalis) to me, which of course is a New Zealand endemic (fodder
for another thread?). Perhaps Steve Mlodinow or Mike O'Brien can confirm or
refute the location of the picture?
I will be very happy to post any additional photos of basic-plumaged Dunlin or
Curlew Sandpiper for our collective enjoyment and scrutiny. Thanks again to
everyone who has chipped in so far.
Angus Wilson
New York City
wilsoa02(AT)med.nyu.edu
[ << | >> | ^^ ]
Subject: Dunlin/Curlew Sandpiper wingprojection
From: Koen Verbanck <verbanckk(AT)online.be>
Date: 7 Jul 2000 6:40am
Dit is een meerdelig bericht in MIME-indeling.
----INCLUDING text/plain MIME SECTION----
Angus Wilson wrote:
>Hopefully the continuing debate on separation of basic-plumage >Dunlin from
Curlew Sandpiper has made it clear that this can be a >tricky ID. We have
heard conflicting, but seemingly reasonable, >opinions from birders in both
North America and Europe and have >reached no strong consensus.
Pictures of birds taken from a certain angle or showing a bird in an odd
position can indeed cause confusion.
In most cases when you actually see the bird identification is mostly
straightforward. This certainly is true in this specific case.
Nevertheless are discussion like the one we are having now interesting
because it forces everyone who is taking part to stand still by things you
normally taken for granted.
Paul Conover wrote:
>The fact that the wingtips seem to distance the tail attracted many
>comments. Maybe this bird is a Curlew, and maybe this is >indisputable
proof, but I have a feeling that it's just a side-effect of >the bird being
in motion. Its wings are pressed more tightly to the >body. Anyone who's
ever measured a wing knows that a flattened >wing can be a great deal longer
than a wing "at rest", and my guess >is that this is what we're seeing here.
I don't think you can explain such a substantial wingprojection by what Paul
is suggesting. The picture shows an active feeding bird, so there is no
reason to believe that we are dealing with a flattened wing (besides both
wings are showing the same clearly projection. I would even suspect that in
the posture the bird is standing in, a flattend wing would not enlarge but
if there would be any changing at all rather diminish the wingprojection).
The information I have tells me that in Dunlin the wings are shorter or
level the tail (Others wrote that the wings can project a little bit). So
because of this substantial wingprojection beyond the tail this bird can't
be a Dunlin. Maybe the discussion should concentrate a bit more on this, in
my opinion, diagnostic(?) feature.
I enclosed a picture of juv. moulting to 1winter plumage Curlew Sandpiper
that I took in Belgium. A fine example of an non-confusing picture.
Greetings Verbanck Koen.
----DELETED image/jpeg MIME SECTION----
[ << | >> | ^^ ]
Subject: Variability of Curlew SP Bill
From: "James H. Barton" <redwing1986(AT)MEDIAONE.NET>
Date: 7 Jul 2000 9:57am
Friends-- On examining the photos and on reading the very
interesting discussion of Small's Dunlin/Curlew SP, I came to realize
that I had based my initial opinion of "Dunlin" primarily on the size,
shape and proportions of the head and bill. In particular, the latter
appeared to be characteristic of Dunlin in that the upper mandible
drooped at the tip instead of curving downward quite evenly throughout
its length.
My personal experience with CUSA is too limited to state that the
>presence< of a "typical Dunlin bill" argues convincingly against CUSA,
absent other evidence. Subscribers with sufficient experience with CUSA
might care to comment. But I can say that the >absence< of a "typical
Curlew Sandpiper bill" cannot be used to reject the possibility of that
species. Other evidence pro and con should continue to be sought.
.
Curlew SP is rare but regular in Massachusetts. Since I see only
one or two a year, I take the opportunity to study the birds carefully.
I have found our spring and summer birds to vary considerably both in
plumage and in bill shape. The upper mandible does not always curve
downward evenly; indeed, on North Monomoy Island in the mid 1980s, I
encountered an individual in nearly full alternate plumage which
presented very nearly a straight bill. It wasn't a Dunlin bill, but it
sure didn't look anything like the CUSA bill in the field guides. As a
result, several participants in the field trip I was leading refused
flatly and loudly to consider Curlew SP despite the evidence of all the
other field marks one could want.
Recently, in fall, I had the opportunity to work on a bird in basic
plumage at Plum Island, MA. It was feeding in a shallow pool close
by, and was clearly visible in silhouette. Its overall structure
suggested CUSA very strongly, but in the glare of the sun, very little
could be seen of its plumage, and the upper mandible, though evenly
curved, was only very slightly curved. I acknowledged that I might be
engaging in wishful thinking. Then the bird flew, showing its rump and
calling about five times, giving several people with me the convincing
evidence they needed for a life bird.
Yours,
Jim Barton
redwing1986(AT)mediaone.net
Cambridge, MA
[ << | >> | ^^ ]
Subject: birdsong guides
From: James Bouldin <jrbouldin(AT)HOTMAIL.COM>
Date: 7 Jul 2000 1:42pm
I wonder if anyone has opinions on any of the CD guides to western US
birdsongs. By my count there are at least three, two by Petersons and one
by Stokes. Of the two by Petersons, there is a great discrepancy in the
number of birdsongs included: 90 vs >500, yet the prices are not much
different. The Stokes guide also has >500 species included. Perhaps the one
with fewer songs is better organized or has a wider range of vocalizations
per species and is more suited for a beginner like myself?
Thank you.
Jim Bouldin
________________________________________________________________________
Get Your Private, Free E-mail from MSN Hotmail at http://www.hotmail.com
[ << | >> | ^^ ]
Subject: Re: birdsong guides
From: Steve Sosensky <Steve(AT)SOSENSKY.COM>
Date: 7 Jul 2000 2:23pm
At 01:41 PM 7/7/00 -0700, James Bouldin wrote:
>I wonder if anyone has opinions on any of the CD guides to western US
>birdsongs. By my count there are at least three, two by Petersons and one
>by Stokes. Of the two by Petersons, there is a great discrepancy in the
>number of birdsongs included: 90 vs >500, yet the prices are not much
>different. The Stokes guide also has >500 species included. Perhaps the one
>with fewer songs is better organized or has a wider range of vocalizations
>per species and is more suited for a beginner like myself?
Whether CD or tape, here is the breakdown on these different sets.
The 90 song Peterson set is called Birding By Ear. Species are grouped by
song type. It teaches you how to distinguish between similar songs, but is
insufficient for field identification.
Of the two other sets, Stokes is more current at this time. It has more
species and includes songs and calls for recently split species (e.g. the
Solitary Vireo complex, and Oak / Juniper Titmouse). Both of these sets are
arranged taxonomically and should match your field guide to a large degree. I
don't believe that the Peterson set has been rearranged to the new AOU
taxonomic order.
I have the Stokes cassette tapes and am very happy with them.
Good birding,
Steve <mailto:steve(AT)sosensky.com>
Steve Sosensky, photographer www.sosensky.com
10834 Blix Street #213 818-508-4946
Toluca Lake, CA 91602 34*09'02" N, 118*22'47" W
Audubon in So. California www.audubon.org/chapter/ca/socal/
San Fernando Valley AS www.audubon.org/chapter/ca/sfvas/
[ << | >> | ^^ ]
Subject: Re: birdsong guides
From: Bill Principe <ThePrincipes(AT)EARTHLINK.NET>
Date: 7 Jul 2000 2:21pm
At 01:41 PM 7/7/2000 -0700, James Bouldin wrote:
>I wonder if anyone has opinions on any of the CD guides to western US
>birdsongs. By my count there are at least three, two by Petersons and one
>by Stokes.
There is another choice. The Peterson Multimedia Guide to North
American Birds CD-ROM. If you have a computer with a CD-ROM drive
handy, there are several reasons why this is a good choice.
. Virtually every North American bird is on the disc.
. It allows random access. You can jump right to the bird
you want, from a taxonomic list, an alphabetical list,
even an ID key.
. Most computer sound cards have a "line out" jack. You can
plug a patch cable from the "line out" to your portable
cassette recorder, and make tapes easily. (The difference
between "line out" and "speaker out" on computer sound
cards is that "line out" bypasses the poor quality audio
amplifier stage in most sound cards, so you get better
quality to the cassette recorder.)
. It is CHEAP. I have seen it as low as $9.95. For some
reasons, it shows up in the discount bin at Office
Depot and other office supply chains.
The disadvantage is that there are fewer samples of each species's
song, and little if any representation of geographical variation.
But it is still a great choice, and a good way to use your computer
while you're waiting for the latest message from Frontiers.
Bill Principe My heart in hiding
La Canada, California Stirred for a bird,
Los Angeles County the achieve of; the mastery of the thing!
34*11'N 118*12'W from "The Windhover"
ThePrincipes(AT)earthlink.net by Gerard Manley Hopkins
[ << | >> | ^^ ]
Subject: Dunlin/Curlew Sandpiper wingprojection
From: DJLauten and KACastelein <birdsong(AT)HARBORSIDE.COM>
Date: 7 Jul 2000 6:55pm
Folks,
Open up to page 160 in Photographic Guide to the Shorebirds of the World.
Take a look at pictures A, C, D, E, G and K. It looks to me that in each
of these cases the wingtips are longer than the tail. Is this from the
angle of the pictures, or is this reality? Look at the photo in question -
I do not think the wing projection in the photo in question is that much
longer than some of these photos to warrant a definative "not a Dunlin".
Love the discussion, very informative, but I can not comment too much
further on the bird since I have zero experience with CUSA.
Dave Lauten
Bandon, OR
birdsong(AT)harborside.com
[ << | >> | ^^ ]
Subject: Ontario Slaty-backed Gull
From: "Robert H. Lewis" <lewis(AT)BWAY.NET>
Date: 7 Jul 2000 9:06pm
Folks,
And now for something completely different.
Whether refreshing, cause for reminiscence, or cause for a groan, here is
news of some gull photos. I have just posted to my web site some photos of
the second accepted record of Slaty-backed Gull (L. schistisagus) from
Ontario, a bird seen by Bob Yukich and Juha Varrela on January 2, 1999.
Thanks to Alfred Adamo and Bob Yukich for getting the material to me.
Bob Lewis
Sleepy Hollow, New York
http://www.bway.net/~lewis/birds/gulls.html
[ << | >> | ^^ ]
Subject: dunlin vs. curlew sandpiper
From: Paul Conover <conover(AT)TALSTAR.COM>
Date: 8 Jul 2000 7:48am
In my last post regarding the mystery sandpiper, I questioned whether
the
pattern evident on the median coverts [dark central wedge or stripe,
basically] of this bird was of use in identifying it to species.
Unfortunately, it seems that we'll need to break this bird down on a
feather-by-feather basis, which is at the same time one of the most
informative and most tedious exercises of this forum.
I was hoping that someone with a collection at hand could provide
descriptions of median coverts for the different plumages of both species,
as it'll be a few weeks before I'll be able to access specimens. If anyone
can, it would be appreciated.
Meanwhile, in browsing through the standard references and various
magazines, I've pored over photos of both species trying to get the hang of
the median covert patterns. From what I can see of exposed sections of this
tract, it seems that Dunlin have median coverts with dark wedges in at
least some basic plumages [it's hard to age some of the birds from
pictures]. This marking is present possibly as early as, or only in, the
first basic.
If the photo of the spread wing that I referred to at
http://www.talstar.com/users/conover/dunlin.html
is that of a first winter bird, [which I gather might be the case, if the
presence of buff margins to the marginal coverts is indicative of retained
juv feathers], then Dunlin may have these feathers as early as first basic,
or maybe only in first basic. Of course, they have them earlier, in
juvenile, and later, in first alternate, but I'm referring to basic
plumages at the moment.
Many of the photos or portrayals of alternate plumage birds show this
pattern also. Again, it's hard to age them, but if these birds are older
than first summer, then the pattern is apparently present in definitive
basic plumage as well, as the median coverts are holdovers from the
previous basic plumage.
If this bird is a Dunlin, the presence of this pattern on the median
coverts supports the ID.
Curlew Sandpiper in juvenile plumage of course has the strong
subterminal
markings which are the diagnostic point that birders searching for this
species often look for. This pattern is present on the median coverts,
which are retained throughout the first year. In all of the pictures of
juvenile Curlew Sandpiper which I have at hand [I have to add that the
majority of the pictures that I can find of this species are of juveniles],
there's no dark stripe or wedge present. The dark in this area of the
feather is limited to the shaft. Cramp and Simmons echoes this description.
Cramp and Simmons describe the median coverts of adult plumages of
Curlew
Sandpiper as having dark shafts only, as well. All of the photos that I
have at hand of definitive plumaged Curlew Sandpipers show a dark shaft
only there, giving the feathers a very even appearance.
If the mystery bird is a Curlew Sandpiper, it can't be a first basic
bird. If it were, we might see some of the subterminal markings, which may
or may not have worn off by April. What we wouldn't see is anywhere near
the amount of dark which is, in fact, present in the center of these median
coverts.
It also seems that it can't be an adult Curlew Sandpiper, as the median
covert pattern fits no adult plumage of that species.
I've felt from the outset that this bird is a Dunlin, and that
confusion
may stem from some observers' inexperience with American subspecies of
Dunlin. The bill length, leg length, and the lack of flank streaking is all
well within the range of American dunlins.
Also, the chances of any given variant of Dunlin in an area where there
are possibly millions of dunlins to choose from is certainly greater than
that of Curlew Sandpiper in an area where they are very rare, and certainly
far greater than of finding what would have been such a hard to ID Curlew
Sandpiper [i.e., a dead ringer for a Dunlin].
I have only ideas as to why the wings seem longer than the tail, but
it's
possible that this field mark is an indicator at best. Perhaps more
attention needs to be paid to this feature among American dunlins. I would
think that it's a pretty minor field mark to use to try to prove the
identification of what would be a very good rarity, especially on the basis
of one photograph.
I also think that we need more and better pictures of these species on
the
internet!
Paul Conover
Louisiana/Florida
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