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ID-FRONTIERS for June 1-4, 2005
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Messages are displayed in the order they were received.
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| Subject | From | Date | Time |
| DOWITCHER IN NEBRASKA | Kevin Karlson | Wed, 1 Jun 2005 | 8:22am |
| Re: DOWITCHER IN NEBRASKA | Alvaro Jaramillo | Wed, 1 Jun 2005 | 9:19am |
| Dowitcher in Nebraska follow-up | Kevin Karlson | Wed, 1 Jun 2005 | 6:38pm |
| Re: DOWITCHER IN NEBRASKA | Matt Kenne | Wed, 1 Jun 2005 | 7:27pm |
| Re: Mystery Gull - Ponce Inlet | Martin Reid | Thu, 2 Jun 2005 | 4:09am |
| Re: Mystery Gull - Ponce Inlet | Larry Manfredi | Thu, 2 Jun 2005 | 5:25am |
| Re: Mystery Gull - Ponce Inlet | Fernando Arce | Thu, 2 Jun 2005 | 7:49am |
| dowitcher subspecies query | julian hough | Thu, 2 Jun 2005 | 10:09am |
| New hybrid warbler photos, and sound files posted | Allen Chartier | Thu, 2 Jun 2005 | 10:28am |
| Re: DOWITCHER IN NEBRASKA | Kevin Karlson | Thu, 2 Jun 2005 | 12:26pm |
| Re: dowitcher subspecies query | Matt Sharp | Thu, 2 Jun 2005 | 1:10pm |
| Re: dowitcher subspecies query | Alvaro Jaramillo | Thu, 2 Jun 2005 | 1:46pm |
| Re: dowitcher subspecies query | Diane and Kayo Roy | Thu, 2 Jun 2005 | 2:11pm |
| RFI; Brewster's Warbler types ratio | Gary l Felton | Thu, 2 Jun 2005 | 2:41pm |
| How difficult, really, are the wood-pewees? | Ted Floyd | Fri, 3 Jun 2005 | 4:52am |
| Re: Mystery Gull - Ponce Inlet | Keith Arnold | Fri, 3 Jun 2005 | 8:00am |
|
To use email addresses replace '(AT)' with '@'.
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Subject: DOWITCHER IN NEBRASKA
From: Kevin Karlson <karlson3(AT)COMCAST.NET>
Date: 1 Jun 2005 8:22am
The Short-billed Dowitcher in the photos is not atypical at all, but a
very representative of a freshly molted hendersoni SB Dowitcher. After
studying dowitchers in e. Texas for the past four springs (where ALL
birds are hendersoni; griseus does not occur on the Texas Gulf coast,
according to our data), I have seen many of these birds in very fresh
plumage, where the orange color on the breast and vent has not yet fully
molted or worn in. The rich color becomes brighter with feather wear as
the pale edges of freshly replaced breeding feathers wear off, which
explains the overall pale appearance to the underparts. Short-bills
typically molt colorful underpart feathers starting with the upper
breast and head, and completing full underpart molt with the lower belly
and vent, unlike LB Dowtichers, who show more color in the vent and
belly prior to completing molt on upper breast and head. The upperparts
are typical of hendersoni, with broad, bright, wide feather edges that
will wear to a brighter orange color with time. Most birds that I see in
this very fresh plumage are in early to mid-April, with brighter
coloration occuring by early to mid-May. This would account for the
shortage of birds in this very fresh plumage in Nebraska in mid-May. The
spotting on the lower flank is also typical of hendersoni, but not
griseus, which would show spotting in the upper breast area but fairly
heavy barring on the lower flanks. The orange coloration that is visible
in the vent area would also be atypical for griseus, which is highly
variable in breeding plumage in respect to the amount of orange
coloration to upper breast and chest and barring on flanks but mostly
exhibits a pale, whitish ventral area. The "kink" in the bill close to
the tip is another trait typical of SB Dowitcher, as opposed to the
tapered bill tip on LB Dowticher. Please excuse the word typical and
atypical that I often use, due to regular variation that occurs in all
SB Dowitcher sub-species.
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Subject: Re: DOWITCHER IN NEBRASKA
From: Alvaro Jaramillo <chucao(AT)COASTSIDE.NET>
Date: 1 Jun 2005 9:19am
Kevin et al.
This is really interesting information, and it makes me want to start
looking more carefully at dowitchers again. I kind of just listen to them
now. I do have two questions. 1) How do you really know that there are no
griseus on the Gulf Coast? It is always tricky to identify any subspecies
outside of its breeding range, and how you interpret variation may be due to
how you are defining the two subspecies 2) there is a large area, mainly in
northern Ontario, where griseus gradually blends in to hendersoni. It is not
a clean break as far as I know, and maybe Ron Pittaway could jump in here if
he has more recent information. So given that there are many intermediates,
and the fact that this Nebraska bird does not look typical for a hendersoni,
how certain can one be of the subspecific identification?
Thanks for the interesting post.
Al
Alvaro Jaramillo
chucao(AT)coastside.net
Half Moon Bay, CA
Field Guides - Birding Tours Worldwide
http://www.fieldguides.com/home.htm
> -----Original Message-----
> From: NBHC ID-FRONTIERS Frontiers of Field Identification
> [mailto:BIRDWG01(AT)LISTSERV.ARIZONA.EDU] On Behalf Of Kevin Karlson
> Sent: Wednesday, June 01, 2005 8:22 AM
> To: BIRDWG01(AT)LISTSERV.ARIZONA.EDU
> Subject: [BIRDWG01] DOWITCHER IN NEBRASKA
>
> The Short-billed Dowitcher in the photos is not atypical at all, but a
> very representative of a freshly molted hendersoni SB Dowitcher. After
> studying dowitchers in e. Texas for the past four springs (where ALL
> birds are hendersoni; griseus does not occur on the Texas Gulf coast,
> according to our data), I have seen many of these birds in very fresh
> plumage, where the orange color on the breast and vent has not yet fully
> molted or worn in. The rich color becomes brighter with feather wear as
> the pale edges of freshly replaced breeding feathers wear off, which
> explains the overall pale appearance to the underparts. Short-bills
> typically molt colorful underpart feathers starting with the upper
> breast and head, and completing full underpart molt with the lower belly
> and vent, unlike LB Dowtichers, who show more color in the vent and
> belly prior to completing molt on upper breast and head. The upperparts
> are typical of hendersoni, with broad, bright, wide feather edges that
> will wear to a brighter orange color with time. Most birds that I see in
> this very fresh plumage are in early to mid-April, with brighter
> coloration occuring by early to mid-May. This would account for the
> shortage of birds in this very fresh plumage in Nebraska in mid-May. The
> spotting on the lower flank is also typical of hendersoni, but not
> griseus, which would show spotting in the upper breast area but fairly
> heavy barring on the lower flanks. The orange coloration that is visible
> in the vent area would also be atypical for griseus, which is highly
> variable in breeding plumage in respect to the amount of orange
> coloration to upper breast and chest and barring on flanks but mostly
> exhibits a pale, whitish ventral area. The "kink" in the bill close to
> the tip is another trait typical of SB Dowitcher, as opposed to the
> tapered bill tip on LB Dowticher. Please excuse the word typical and
> atypical that I often use, due to regular variation that occurs in all
> SB Dowitcher sub-species.
>
>
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> bin/wa?SUBED1=birdwg01
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Subject: Dowitcher in Nebraska follow-up
From: Kevin Karlson <karlson3(AT)COMCAST.NET>
Date: 1 Jun 2005 6:38pm
I want to qualify some statements that I made in my recent posting to
the Nebraska hendersoni Dowitcher. First of all, I forgot to sign my
name to the posting, which was an oversight due to my inexperience with
posting on the listserve and I was alerted to this oversight by a
subscriber. Secondly, I should have qualified my statement that "ALL
dowitchers on Texas' Gulf Coast are hendersoni" to "all dowitchers that
I have identified in SPRING are hendersoni". During the last five years,
I have visited S. Padre Island after leading tours at the Rio Grande
Valley Bird Festival. I regularly go the S. Padre to photograph
shorebirds before or after the festival, and I have some photos of dark
birds that could possibly be griseus, or even Long-billed Dowitchers.
Most of the criteria that we (co-authors Michael O'Brien and Richard
Crossley, The Shorebird Guide) use to identify dowitchers to species
point to Long-billed on several questionable birds, but the overall size
and bill shape and lengths are consistent with Short-billed Dowitcher. I
am not as confident in the distribution of hendersoni dowitchers during
fall migration as I am in spring, and it is entirely possible that
griseus might move along the Texas coast in fall. If they do, they are
in the extreme minority, with most, if not all, migrating/wintering
dowitchers on the lower Texas Coast hendersoni. I have also photographed
dowitchers in the Cayman Islands in early March, and all were hendersoni
in nonbreeding plumage.
To answer Alvaro's question about why we are sure about separating
sub-species, I should learn to never use the words "always" or "all"
when referring to a conclusion, regardless of how much study when into
it. I am very confident, however, that I have never been able to
identify, or even pose a "possible" griseus dowitcher along the Texas
Coast in March-May over the last four years. Michael O'Brien, who leads
tours for WINGS to the upper Texas Coast each spring, shares my
conclusions. I have looked at thousands of individuals during this time,
both in full non-breeding, transition and breeding plumage, and none
even suggested the wide range of appearances of griseus that we see in
the northeast every spring during migration. We get tens of thousands of
griseus Short-bills every May migrating and staging in the NJ tidal
marshes, with about five percent hendersoni mixed in for direct
comparison. If you travel a short twenty miles as the crow flies from
Cape May to Delaware, that number probably increases to about 40 percent
(please don't ask me for details about this number. I am basing it on 25
years of birding these locations), reflecting a more interior flyway
influence of Bombay Hook and surrounding Delaware Bayshore locations. It
is usually immediately obvious when a hendersoni appears in a flock of
griseus dowitchers, both by the general larger size and intensity of
coloration to the complete orange underparts. The width and added
brightness of the back feather fringes is also usually obvious in
hendersoni, especially with full breeding plumage birds. Problem birds
do occur, however, that occasionally require extra scrutiny, and
sometimes result in caution to putting any subspecies name to certain
individuals. I have never, however, seen any of these birds in Texas
during spring migration. When I visited Galveston, High Island, Bolivar
Flats this past early March, most of the dowitchers were in nonbreeding
plumage. Hendersoni is fairly distinctive in nonbreeding plumage when
compared to griseus, mostly by the wide, pale upperparts feather edges.
They are also quite a bit paler overall in comparison to nonbreeding
griseus, although birds in worn plumage could pose a problem. Many
spring nonbreeding hendersoni have lost the bright feather edges to the
upper back, but show a good deal of wide, pale fringing to the wing
coverts and tertials, which were molted later in the season. We will be
covering molt shedule and timing of dowitchers and all other shorebirds
in our book, which should be available next spring. On the Florida Gulf
Coast, where both species occur in migration, a direct comparison of
griseus and hendersoni is possible.
In breeding plumage, hendersoni typically shows a bright, orange
coloration from the upper breast to vent, while griseus exhibits a
mostly, clean whitish vent and lower belly. Griseus is highly variable
in breeding plumage, in my opinion much more so than hendersoni. They
can show a good deal of orange color to the upper and central breast
area, or somewhat restricted, broken paler color during migration in
mid-to late May. They typically show spotting on the upper breast and
upper flanks, but unlike hendersoni, have a good deal of fairly heavy
barring on the lower flanks. First summer birds that molt only a portion
of breeding feathers during their first calendar year can pose a
problem, and we often have a number of these individuals spending the
summer in NJ, with no hormonal urge to fly any further north to breeding
areas. Molting birds that appear in July-Aug are a bit more difficult,
but once again the larger size and complete orange underparts are
typically helpful. There is a good possibility that I am overlooking
intermediate birds and passing them off as griseus, or not ascribing a
subspecies name to them, but they are definitely in the low minority of
individuals. I am surprised that Alvaro would mention that there are
many intermediate plumaged birds, since the number of puzzling
individuals in spring and late summer are few compared to the tremendous
number of griseus that we regularly see. I also have not encountered any
of these individuals in east Texas, but given that the overlap
population is in Ontario, I would suspect that these birds move along
the Atlantic flyway in migration in spring. I do see birds in NJ in
spring and July-Aug. in NJ that cause a few problems in regards to
subspecies, but the number is typically very small.
As far as Alvaro's comment that this Nebraska dowitcher is not typical
of hendersoni, I respectfully disagree. I see numbers of birds in this
exact plumage state near High Island/Galveston every spring, and we are
using a two photos that are virtually identical to the Nebraska bird in
our book. I will be posting these on my friend Lloyd Spitalnik's website
tomorrow (www.lloyd22.com/gallery15.htm) for anyone who wants to see
them. One is a sleeping bird that we use to separate posture and weight
distribution differences between Long and Short-billed Dowitchers, and
another is used to compare sizes of Stilt Sandpiper to other similarly
sized shorebirds. I have numerous photos of similar plumaged hendersoni
dowitchers from this area, but the time frame is generally late March to
mid-April. By May, most hendersoni have molted into a more complete
breeding plumage, and the back feathers have worn the pale fringes to a
more rich orange color. Before I became interested in subspecies of
dowitchers, I probably would have looked at these birds and just passed
them off as SB Dowitchers, but focusing on subspecies and photographing
many individuals has brought some decent conclusions. I am not proposing
that everything I am saying is 100 percent correct, and I am not used to
airing my opinions in public, but I do enjoy sharing what I have
recently learned with others and learning from the criticism and
responses that come in.
I do not consider myself an expert on dowitchers, but I have been
listening and learning from Michael and Richard for the past three
years, and things make a good deal more sense now than five years ago.
We will be comparing in depth Long and Short-billed Dowitchers in our
new book, and include a number of criteria that have not been published
in any field guides and that have been proven to truly work in the field
over a period of years. We attempt to identify the subspecies of SB
Dowitcher in juvenile, nonbreeding, transition and breeding plumage, and
use the word "possible" in several photo captions. If we get people
thinking a bit harder about some of these common shorebirds that have
given birders trouble for many years, then our job has been a success.
Thanks for listening.
Kevin Karlson
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Subject: Re: DOWITCHER IN NEBRASKA
From: Matt Kenne <mkenne(AT)NETAMUMAIL.COM>
Date: 1 Jun 2005 7:27pm
Hi All,
I understand the darkening of feathers by the wearing off of a paler
edge to a different color subterminally- breast /belly feathers in
dowitchers, face/chest in Lapland Longspur, white markings on edges of
the back feathers in LBDO, but I don't understand how this would occur
on the back of this particular dowitcher (and, by extension, Texas
hendersonis). If the pale edges wore down on this bird, there would only
be the dark centers to the feathers remaining- I can't see from these
photos where there would be anything left that would appear like the
very wide and buffy/orangish/golden fringe on our usual hendersoni SBDOs
around here. And the edge certainly couldn't "fade" to a darker shade
than what seems to be the color in these photos, could it? Where does
the "orange" come from?
Matthew Kenne
Algona, Iowa
mkenne(AT)netamumail.com
Kevin Karlson wrote:
> The Short-billed Dowitcher in the photos is not atypical at all, but a
> very representative of a freshly molted hendersoni SB Dowitcher. After
> studying dowitchers in e. Texas for the past four springs (where ALL
> birds are hendersoni; griseus does not occur on the Texas Gulf coast,
> according to our data), I have seen many of these birds in very fresh
> plumage, where the orange color on the breast and vent has not yet
> fully molted or worn in. The rich color becomes brighter with feather
> wear as the pale edges of freshly replaced breeding feathers wear
> off, which explains the overall pale appearance to the underparts.
> Short-bills typically molt colorful underpart feathers starting with
> the upper breast and head, and completing full underpart molt with the
> lower belly and vent, unlike LB Dowtichers, who show more color in the
> vent and belly prior to completing molt on upper breast and head. The
> upperparts are typical of hendersoni, with broad, bright, wide feather
> edges that will wear to a brighter orange color with time.
And in his latest post:
"By May, most hendersoni have molted into a more complete breeding
plumage, and the back feathers have worn the pale fringes to a more rich
orange color."
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Subject: Re: Mystery Gull - Ponce Inlet
From: Martin Reid <upupa(AT)AIRMAIL.NET>
Date: 2 Jun 2005 4:09am
Dear all,
I am inclined to think that this is a HERG. In TEXAS we are blessed with a
small number of such gulls from late Spring through the Summer, and I've
previously tried to make them into all kinds of things...
I don't think it's a RBGU for the following reasons:
The rear structure is wrong, with the wings short and tail long (wear
cannot account for this.) RGBUs always have a long-winged, short-tailed look.
The eye is not dark, thus if an RBGU it must be 3CY; I've looked at loads
of first-Spring RGBUs and have yet to see one with anything but dark eyes.
The dark smudging on the underparts is not staining but the remains of a
more extensive natural coloration; no plumage of RBGU has this kind of
smudginess - especially as a 3CY.
Some of the few scaps that show any pattern have dark shafts - this again
is not normal for RBGU, especially a 3CY.
Every winter I see a few small (presumably female) dainty, dove-headed
HERGs that I try to make into something else, but they are just small,
dainty HERGs... Thus this looks as I would expect some worn retarded
3CY/advanced 2CY HERGs to look.
Cheers,
Martin
Martin Reid
San Antonio, Texas
mailto:upupa(AT)airmail.net
http://www.martinreid.com
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Subject: Re: Mystery Gull - Ponce Inlet
From: Larry Manfredi <birderlm(AT)BELLSOUTH.NET>
Date: 2 Jun 2005 5:25am
It is possible that it is a Herring Gull but how can you account for the
small size? Herring Gulls are larger than Lesser Black-backed Gulls and
Ring-billed Gulls are smaller than Lesser Black-backed Gulls, Bob said the
bird was smaller than a Lesser Black-backed Gull. Of course it could be a
runt Herring Gull but it would have to be a pretty small runt pretty far
outside the range of a normal Herring Gull. The other point is that on my
computer screen the eye of the bird is dark not yellow.
Another point that I would like to make is that my first impression and what
Dexter thought, is that it is a Ring-billed Gull regardless of what the
plumage looks like. To me it has more of the "Jizz" for a Ring-billed than
a Herring Gull.
Larry Manfredi
P.S. As I am finishing this up Bob is telling us that the bird was the same
size as a Lesser Black-backed Gull, what's up with that Bob? How is this
going to hold up in a court of Law??? Below is what you wrote yesterday
Bob!!
Size was just a tad smaller than Lesser Black-backed, which was seen nearby
by Dex and Alex,
-----Original Message-----
From: NBHC ID-FRONTIERS Frontiers of Field Identification
[mailto:BIRDWG01(AT)LISTSERV.ARIZONA.EDU]On Behalf Of Martin Reid
Sent: Thursday, June 02, 2005 7:19 AM
To: BIRDWG01(AT)LISTSERV.ARIZONA.EDU
Subject: Re: [BIRDWG01] Mystery Gull - Ponce Inlet
Dear all,
I am inclined to think that this is a HERG. In TEXAS we are blessed with a
small number of such gulls from late Spring through the Summer, and I've
previously tried to make them into all kinds of things...
I don't think it's a RBGU for the following reasons:
The rear structure is wrong, with the wings short and tail long (wear
cannot account for this.) RGBUs always have a long-winged, short-tailed
look.
The eye is not dark, thus if an RBGU it must be 3CY; I've looked at loads
of first-Spring RGBUs and have yet to see one with anything but dark eyes.
The dark smudging on the underparts is not staining but the remains of a
more extensive natural coloration; no plumage of RBGU has this kind of
smudginess - especially as a 3CY.
Some of the few scaps that show any pattern have dark shafts - this again
is not normal for RBGU, especially a 3CY.
Every winter I see a few small (presumably female) dainty, dove-headed
HERGs that I try to make into something else, but they are just small,
dainty HERGs... Thus this looks as I would expect some worn retarded
3CY/advanced 2CY HERGs to look.
Cheers,
Martin
Martin Reid
San Antonio, Texas
mailto:upupa(AT)airmail.net
http://www.martinreid.com
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Subject: Re: Mystery Gull - Ponce Inlet
From: Fernando Arce <fernand_arce(AT)YAHOO.ES>
Date: 2 Jun 2005 7:49am
I missed the original post. can any one send it again ?
Regards
Fernando
----- Original Message -----
From: "Larry Manfredi" <birderlm(AT)BELLSOUTH.NET>
To: <BIRDWG01(AT)LISTSERV.ARIZONA.EDU>
Sent: Thursday, June 02, 2005 2:25 PM
Subject: Re: [BIRDWG01] Mystery Gull - Ponce Inlet
> It is possible that it is a Herring Gull but how can you account for the
> small size? Herring Gulls are larger than Lesser Black-backed Gulls and
> Ring-billed Gulls are smaller than Lesser Black-backed Gulls, Bob said the
> bird was smaller than a Lesser Black-backed Gull. Of course it could be a
> runt Herring Gull but it would have to be a pretty small runt pretty far
> outside the range of a normal Herring Gull. The other point is that on my
> computer screen the eye of the bird is dark not yellow.
>
> Another point that I would like to make is that my first impression and
> what
> Dexter thought, is that it is a Ring-billed Gull regardless of what the
> plumage looks like. To me it has more of the "Jizz" for a Ring-billed
> than
> a Herring Gull.
>
> Larry Manfredi
>
> P.S. As I am finishing this up Bob is telling us that the bird was the
> same
> size as a Lesser Black-backed Gull, what's up with that Bob? How is this
> going to hold up in a court of Law??? Below is what you wrote yesterday
> Bob!!
>
> Size was just a tad smaller than Lesser Black-backed, which was seen
> nearby
> by Dex and Alex,
>
>
>
> -----Original Message-----
> From: NBHC ID-FRONTIERS Frontiers of Field Identification
> [mailto:BIRDWG01(AT)LISTSERV.ARIZONA.EDU]On Behalf Of Martin Reid
> Sent: Thursday, June 02, 2005 7:19 AM
> To: BIRDWG01(AT)LISTSERV.ARIZONA.EDU
> Subject: Re: [BIRDWG01] Mystery Gull - Ponce Inlet
>
> Dear all,
> I am inclined to think that this is a HERG. In TEXAS we are blessed with
> a
> small number of such gulls from late Spring through the Summer, and I've
> previously tried to make them into all kinds of things...
> I don't think it's a RBGU for the following reasons:
> The rear structure is wrong, with the wings short and tail long (wear
> cannot account for this.) RGBUs always have a long-winged, short-tailed
> look.
> The eye is not dark, thus if an RBGU it must be 3CY; I've looked at loads
> of first-Spring RGBUs and have yet to see one with anything but dark eyes.
> The dark smudging on the underparts is not staining but the remains of a
> more extensive natural coloration; no plumage of RBGU has this kind of
> smudginess - especially as a 3CY.
> Some of the few scaps that show any pattern have dark shafts - this again
> is not normal for RBGU, especially a 3CY.
>
> Every winter I see a few small (presumably female) dainty, dove-headed
> HERGs that I try to make into something else, but they are just small,
> dainty HERGs... Thus this looks as I would expect some worn retarded
> 3CY/advanced 2CY HERGs to look.
> Cheers,
> Martin
>
>
> Martin Reid
> San Antonio, Texas
> mailto:upupa(AT)airmail.net
> http://www.martinreid.com
>
>
> Join or Leave BIRDWG01:
> http://listserv.arizona.edu/cgi-bin/wa?SUBED1=birdwg01
>
> Archives: http://listserv.arizona.edu/archives/birdwg01.html
>
>
> Join or Leave BIRDWG01:
> http://listserv.arizona.edu/cgi-bin/wa?SUBED1=birdwg01
>
> Archives: http://listserv.arizona.edu/archives/birdwg01.html
>
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Subject: dowitcher subspecies query
From: julian hough <jrhough1(AT)SNET.NET>
Date: 2 Jun 2005 10:09am
----INCLUDING text/plain MIME SECTION----
I've been away and am just catching up on the posts re:the Nebraska dowitcher. I
read Kevin's and Alvaro's posts with interests since I have had some queries of
my own regarding sub-specific identification of hendersonii.
I wrote an article in Birdwatch, a UK publication (some years ago now, don't
have the reference handy) about the potential identification pitfalls of
summer-garbed Long-billed Dowitcher and hendersonii and griseus Short-billed
Dowitchers.
At the time my field experience and references for that article were of birds
passing through Cape May between July-September, where griseus were predominant
but included varying numbers of hendersonii.
Where I live now, in CT, I see fewer dowichers in total, so breeding-plumaged
hendersonii are proportionately much scarcer during May-September at my
watchpoints, averaging 2 individuals per year.
My main query, and one that seems at odds with kevin's experiences, is that I
frequently see griseus with some colour on the underparts behind the legs and
intruding onto the ventral areas in a patchy, not continuous, pattern. I have
seen such birds in CT and in New Jersey, or wherever I have been looking at
dowitchers in the east.
I believe Alvaro and I have talked about this privately in the past, especially
with regards to the "intermediates" and the potential pairing of hendersonii and
griseus (which I believe has been documented from Ontario?).
If griseus have pale, whitish ventral areas, are these birds with patchy
colouring in the vent intermediates, hybrid hendersonii x griseus, or possibly
more likely, just individual variations of griseus?
If Alvaro or Kevin et al. that have obviously put time into dowitchers, and have
any helpful insights into these birds, I'd be keen to hear there explanations.
I'm keen to hear also how to identify hendersonii in non-breeding plumages since
this will be very interesting given current knowledge.
best,
Julian Hough,
CT, USA
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Subject: New hybrid warbler photos, and sound files posted
From: Allen Chartier <amazilia1(AT)COMCAST.NET>
Date: 2 Jun 2005 10:28am
Birders and Banders,
After much delay, I have finally put together a web page with all 15 photos,
and three sound files (with sonograms) of the hybrid warbler I captured and
banded at Metro Beach Metropark, Michigan, on May 14, 2005. Only four photos
of this bird have been posted previously, so there may be more grist for the
mill in the additional material :-)
I am still very interested in any additional comments anyone may have on
this bird.
Go to: http://www.amazilia.net/images/Birds/NewWarblers/Hybrid_Warbler.htm
Thanks!
Allen Chartier
amazilia1(AT)comcast.net
1442 West River Park Drive
Inkster, MI 48141
Website: http://www.amazilia.net
Michigan HummerNet: http://www.amazilia.net/MIHummerNet/index.htm
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Subject: Re: DOWITCHER IN NEBRASKA
From: Kevin Karlson <karlson3(AT)COMCAST.NET>
Date: 2 Jun 2005 12:26pm
A Response to queries by Matt Kenne:
I looked at a number of breeding hendersoni photos from Churchill,
representing about ten different birds, and noticed that the back
feathers still have a remnant of the whitish feather tips that is
characteristic of most freshly molted hendersonin in Texas. These SB
Dowitchers on Texas Upper Coast mostly show white fringes to the TIPS of
upperpart feathers in very fresh plumage, with broad internal notches
and sides of the feathers mostly bright orange. The Churchill birds,
shot in mid-June, have worn most of these feather tips off, but tattered
remants of these white fringes remain. It is not obvious at first
glance, due to the tips of the feathers wearing off first. Some of the
Texas' birds, as well as the Nebraska bird, show a good deal more of the
white feather fringing, but the overall pattern is still mostly orange.
I am not sure how to explain why they appear mostly orange fringed on
the breeding ground, while freshly molted birds show various amounts of
white fringing. This scenario is similar to Baird's Sandpipers, that
show up in Texas in April and May with buff to light brownish centered
upperparts and broad buff fringes to all upperpart feathers except wing
coverts. After working the Alaskan Arctic Coastal Tundra near Prudhoe
Bay for four years as a shorebird biologist in the early 90's, I can
tell you that all Bairds show dark blackish feather centers with bright
silvery feather edges to upperpart feathers on the breeding grounds,
except for later molted nonbreeding-like brownish wing coverts.. These
are the same birds that I see in Texas in freshly molted breeding
plumage that are mostly buff and brownish in color. Maybe a shorebird
scientist who works with anatomy biology or variations in pigment
distribution can answer your questions, but I surely cannot. I can only
tell you what I see in Texas every year, and these hendersoni
Short-bills virtually all have crisp whitish feather tip edges to
upperparts, mixed in with the characteristic bright orange sides and
internal notches. Check out the 3 photos on my friend Lloyd Spitalnik's
website (www.lloyd22.com/gallery15.htm) for a few photos of these birds,
which I will be posting later today (June 2). They are not odd birds at
all, but freshly molted hendersoni dowitchers. I have also reviewed
other photos of molting hendersoni dowitchers that I have taken, and
some of these are more characteristic with mostly orange feather
fringes, but still have moderate amounts of white fringing to the tips
of the upperpart feathers. These examples of added white feather edges
could just be a matter of uneven pigment distribution, given the close
proximity of the orange feather sides and internal notches. I have also
posted a comparison shot of late July/early Aug. hendersoni and griseus
to show the subtle similarities of these two subspecies, especially
during transition molt. Notice that the three griseus are in obvious
feather molt, while the hendersoni has not started molting at all. The
markings on the flanks are fairly heavy on hendersoni, but not heavily
BARRED as shown on the three griseus. The brightness of now worn buff
feather edging on the upperparts is also more pronounced on hendersoni.
Kevin Karlson
Matt Kenne wrote:
> Hi All,
>
> I understand the darkening of feathers by the wearing off of a paler
> edge to a different color subterminally- breast /belly feathers in
> dowitchers, face/chest in Lapland Longspur, white markings on edges of
> the back feathers in LBDO, but I don't understand how this would occur
> on the back of this particular dowitcher (and, by extension, Texas
> hendersonis). If the pale edges wore down on this bird, there would
> only be the dark centers to the feathers remaining- I can't see from
> these photos where there would be anything left that would appear like
> the very wide and buffy/orangish/golden fringe on our usual hendersoni
> SBDOs around here. And the edge certainly couldn't "fade" to a darker
> shade than what seems to be the color in these photos, could it? Where
> does the "orange" come from?
>
> Matthew Kenne
> Algona, Iowa
> mkenne(AT)netamumail.com
>
> Kevin Karlson wrote:
>
>> The Short-billed Dowitcher in the photos is not atypical at all, but
>> a very representative of a freshly molted hendersoni SB Dowitcher.
>> After studying dowitchers in e. Texas for the past four springs
>> (where ALL birds are hendersoni; griseus does not occur on the Texas
>> Gulf coast, according to our data), I have seen many of these birds
>> in very fresh plumage, where the orange color on the breast and vent
>> has not yet fully molted or worn in. The rich color becomes brighter
>> with feather wear as the pale edges of freshly replaced breeding
>> feathers wear off, which explains the overall pale appearance to the
>> underparts. Short-bills typically molt colorful underpart feathers
>> starting with the upper breast and head, and completing full
>> underpart molt with the lower belly and vent, unlike LB Dowtichers,
>> who show more color in the vent and belly prior to completing molt on
>> upper breast and head. The upperparts are typical of hendersoni, with
>> broad, bright, wide feather edges that will wear to a brighter orange
>> color with time.
>
>
> And in his latest post:
>
> "By May, most hendersoni have molted into a more complete breeding
> plumage, and the back feathers have worn the pale fringes to a more
> rich orange color."
>
>
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Subject: Re: dowitcher subspecies query
From: Matt Sharp <sharp(AT)ACNATSCI.ORG>
Date: 2 Jun 2005 1:10pm
Though I don't have any input on the birds at hand it seems this discussion
is getting to the fuzzy line between field ID and taxonomy. The comments
below are mainly an attempt to clarify the taxonomic side so please correct
them
as needed.
>If griseus have pale, whitish ventral areas, are these birds with patchy
colouring in
>the vent intermediates, hybrid hendersonii x griseus, or possibly more likely,
just
>individual variations of griseus?
I don't think this question can really be answered without knowing where birds
are
breeding. It may be possible to answer it genetically to a degree but even then
you would still have to slap a name on whatever genetic unit you were using to
identify griseus vs hendersonii.
If sub-specific names are an attempt to categorize geographic variation then
you can't identify an individual bird to subspecies, with certainty, without
knowing the geographic part, and in this instance it appears to be the breeding
geography that is crucial.
Also a subspecies is almost by definition an intermediate, a population/taxa
where there is at least the potential for gene flow from another
population/taxa
so I don't know if it makes sense to talk about intermediates between
subspecies.
If the 2 subspecies are in contact and producing first generation offspring
than odds are that they have been in contact long enough to produce multiple
generations of offspring and there would be no difference between variation
and intergradation.
Using plumage and/or morphology alone to identify subspecies easily leads
to a catch 22, especially when the forms are clinal as may be the case here
with hendersonii and griseus blending into each other east to west (not
sure where caurinus fits in though).
Didn't someone say we would be moving on to shorebirds in response to
frustration over gulls a little while back?
Matt
Matt Sharp
Collection Manager
VIREO/ANS
1900 Benjamin Franklin Pkwy.
Philadelphia PA 19103
http://vireo.acnatsci.org
(tel.) 215-299-1069
(fax) 215-299-1182
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Subject: Re: dowitcher subspecies query
From: Alvaro Jaramillo <chucao(AT)COASTSIDE.NET>
Date: 2 Jun 2005 1:46pm
Folks
My info on the intermediates comes from study of specimens from the
breeding area. The specimens I looked at were in the National Museum of
Nature in Ottawa, and the Royal Ontario Museum in Toronto. Some of this
stuff was published a long time ago in a hard to find publication:
Jaramillo, A., R. Pittaway, and P. Burke. 1991. The identification and
migration of breeding plumaged dowitchers in southern Ontario. Birders
Journal 1(1): 8-25. It was the first article ever in Birders Journal (RIP)
so it is hard to come by.
Here are a couple of excerpts:
"The collection at the Royal Ontario Museum holds skins of six individuals
taken during the breeding season in northern Ontario; the National Museum of
Nature has another size birds of the same status. Of these 12 birds, we
identified three as L.g.hendersoni, two as L.g.griseus and seven as
intermediate in plumage. The intermediates ranged from birds that looked
mostly like L.g.hendersoni but with large amounts of white on the underparts
to individuals that looked like L.g.griseus in the pattern of spotting but
with extensive amounts of colour below. Pitelka (1950) looked at two of the
Ontario birds from the ROM. He classified one of them as L.g.griseus but the
other he considered a probable intermediate. He also mentions that the first
may also be an intermediate, but that it looked most like L.g.griseus."
We also thought that Churchill hendersoni showed a great deal of variation
and that they may be at the end of this cline of intermediates.
"...PItelka (1950) found that Manitoba birds were definite L.g.hendersoni,
but that they tended to have more white below and more spotting than typical
birds from further west. He also found Manitoba individuals to be
intermediate in measurements between L.g.griseus and typical L.g.hendersoni.
Conover (1941) found a female from Churchill to be intermediate in nature
between the two forms. Jehl and Smith (1970) cite that several L.g.griseus
have been collected in migration in Churchill...."
Citations are:
Conover, H.B. 1941. A study of dowitchers. Auk 58L 376-380.
Jehl, J.R. Jr. and B.A. Smith. 1970. Birds of the Churchill Region,
Manitoba. Special Publication Number 1. Manitoba Museum of Man and Nature.
Winnipeg, Man.
Pitelka, F.A. 1950. Geographic variation and the species problem in the
shore-bird genus Limnodromus. Univ. Calif. Publ. Zool. 50: 1-108.
I disagree that a subspecies is an intermediate almost by definition. The
fact that subspecies are not reproductively isolated from each other does
not necessarily make them intermediate. The problem is that we have a lot of
poorly defined subspecies that are clinal. Note that many of our subspecies
are allopatric and quite well defined.
Cheers
Alvaro
Alvaro Jaramillo
chucao(AT)coastside.net
Half Moon Bay, CA
Field Guides - Birding Tours Worldwide
http://www.fieldguides.com/home.htm
> -----Original Message-----
> From: NBHC ID-FRONTIERS Frontiers of Field Identification
> [mailto:BIRDWG01(AT)LISTSERV.ARIZONA.EDU] On Behalf Of Matt Sharp
> Sent: Thursday, June 02, 2005 1:13 PM
> To: BIRDWG01(AT)LISTSERV.ARIZONA.EDU
> Subject: Re: [BIRDWG01] dowitcher subspecies query
>
> Though I don't have any input on the birds at hand it seems this
> discussion
> is getting to the fuzzy line between field ID and taxonomy. The comments
> below are mainly an attempt to clarify the taxonomic side so please
> correct them
> as needed.
>
> >If griseus have pale, whitish ventral areas, are these birds with patchy
> colouring in
> >the vent intermediates, hybrid hendersonii x griseus, or possibly more
> likely, just
> >individual variations of griseus?
>
> I don't think this question can really be answered without knowing where
> birds are
> breeding. It may be possible to answer it genetically to a degree but even
> then
> you would still have to slap a name on whatever genetic unit you were
> using to
> identify griseus vs hendersonii.
>
> If sub-specific names are an attempt to categorize geographic variation
> then
> you can't identify an individual bird to subspecies, with certainty,
> without
> knowing the geographic part, and in this instance it appears to be the
> breeding geography that is crucial.
>
> Also a subspecies is almost by definition an intermediate, a
> population/taxa
> where there is at least the potential for gene flow from another
> population/taxa
> so I don't know if it makes sense to talk about intermediates between
> subspecies.
> If the 2 subspecies are in contact and producing first generation
> offspring
> than odds are that they have been in contact long enough to produce
> multiple
> generations of offspring and there would be no difference between
> variation
> and intergradation.
>
> Using plumage and/or morphology alone to identify subspecies easily leads
> to a catch 22, especially when the forms are clinal as may be the case
> here
> with hendersonii and griseus blending into each other east to west (not
> sure where caurinus fits in though).
>
> Didn't someone say we would be moving on to shorebirds in response to
> frustration over gulls a little while back?
>
> Matt
>
>
> Matt Sharp
> Collection Manager
> VIREO/ANS
> 1900 Benjamin Franklin Pkwy.
> Philadelphia PA 19103
> http://vireo.acnatsci.org
> (tel.) 215-299-1069
> (fax) 215-299-1182
>
>
> Join or Leave BIRDWG01: http://listserv.arizona.edu/cgi-
> bin/wa?SUBED1=birdwg01
>
> Archives: http://listserv.arizona.edu/archives/birdwg01.html
>
> --
> No virus found in this incoming message.
> Checked by AVG Anti-Virus.
> Version: 7.0.322 / Virus Database: 267.4.1 - Release Date: 6/2/2005
>
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Subject: Re: dowitcher subspecies query
From: Diane and Kayo Roy <kayoroy(AT)NIAGARA.COM>
Date: 2 Jun 2005 2:11pm
Alvaro and others
Al, I have a copy of Birder's Journal Volume 1 Number 1 that contains the
article you wrote with Ron and Peter. Anyone wishing a photocopy of this
article should e-mail me privately, and I would be more than happy to mail
out copies. All the best Al.
Kayo
Kayo Roy
13 Kinsman Court
Fonthill, ON
L0S 1E3
kayoroy(AT)niagara.com
----- Original Message -----
From: "Alvaro Jaramillo" <chucao(AT)COASTSIDE.NET>
To: <BIRDWG01(AT)LISTSERV.ARIZONA.EDU>
Sent: Thursday, June 02, 2005 4:46 PM
Subject: Re: [BIRDWG01] dowitcher subspecies query
> Folks
>
> My info on the intermediates comes from study of specimens from the
> breeding area. The specimens I looked at were in the National Museum of
> Nature in Ottawa, and the Royal Ontario Museum in Toronto. Some of this
> stuff was published a long time ago in a hard to find publication:
> Jaramillo, A., R. Pittaway, and P. Burke. 1991. The identification and
> migration of breeding plumaged dowitchers in southern Ontario. Birders
> Journal 1(1): 8-25. It was the first article ever in Birders Journal (RIP)
> so it is hard to come by.
>
> Here are a couple of excerpts:
>
> "The collection at the Royal Ontario Museum holds skins of six individuals
> taken during the breeding season in northern Ontario; the National Museum
of
> Nature has another size birds of the same status. Of these 12 birds, we
> identified three as L.g.hendersoni, two as L.g.griseus and seven as
> intermediate in plumage. The intermediates ranged from birds that looked
> mostly like L.g.hendersoni but with large amounts of white on the
underparts
> to individuals that looked like L.g.griseus in the pattern of spotting but
> with extensive amounts of colour below. Pitelka (1950) looked at two of
the
> Ontario birds from the ROM. He classified one of them as L.g.griseus but
the
> other he considered a probable intermediate. He also mentions that the
first
> may also be an intermediate, but that it looked most like L.g.griseus."
>
> We also thought that Churchill hendersoni showed a great deal of variation
> and that they may be at the end of this cline of intermediates.
>
> "...PItelka (1950) found that Manitoba birds were definite L.g.hendersoni,
> but that they tended to have more white below and more spotting than
typical
> birds from further west. He also found Manitoba individuals to be
> intermediate in measurements between L.g.griseus and typical
L.g.hendersoni.
> Conover (1941) found a female from Churchill to be intermediate in nature
> between the two forms. Jehl and Smith (1970) cite that several L.g.griseus
> have been collected in migration in Churchill...."
>
> Citations are:
>
> Conover, H.B. 1941. A study of dowitchers. Auk 58L 376-380.
> Jehl, J.R. Jr. and B.A. Smith. 1970. Birds of the Churchill Region,
> Manitoba. Special Publication Number 1. Manitoba Museum of Man and Nature.
> Winnipeg, Man.
> Pitelka, F.A. 1950. Geographic variation and the species problem in the
> shore-bird genus Limnodromus. Univ. Calif. Publ. Zool. 50: 1-108.
>
> I disagree that a subspecies is an intermediate almost by definition. The
> fact that subspecies are not reproductively isolated from each other does
> not necessarily make them intermediate. The problem is that we have a lot
of
> poorly defined subspecies that are clinal. Note that many of our
subspecies
> are allopatric and quite well defined.
>
> Cheers
>
> Alvaro
>
> Alvaro Jaramillo
> chucao(AT)coastside.net
> Half Moon Bay, CA
>
> Field Guides - Birding Tours Worldwide
> http://www.fieldguides.com/home.htm
>
> > -----Original Message-----
> > From: NBHC ID-FRONTIERS Frontiers of Field Identification
> > [mailto:BIRDWG01(AT)LISTSERV.ARIZONA.EDU] On Behalf Of Matt Sharp
> > Sent: Thursday, June 02, 2005 1:13 PM
> > To: BIRDWG01(AT)LISTSERV.ARIZONA.EDU
> > Subject: Re: [BIRDWG01] dowitcher subspecies query
> >
> > Though I don't have any input on the birds at hand it seems this
> > discussion
> > is getting to the fuzzy line between field ID and taxonomy. The comments
> > below are mainly an attempt to clarify the taxonomic side so please
> > correct them
> > as needed.
> >
> > >If griseus have pale, whitish ventral areas, are these birds with
patchy
> > colouring in
> > >the vent intermediates, hybrid hendersonii x griseus, or possibly more
> > likely, just
> > >individual variations of griseus?
> >
> > I don't think this question can really be answered without knowing where
> > birds are
> > breeding. It may be possible to answer it genetically to a degree but
even
> > then
> > you would still have to slap a name on whatever genetic unit you were
> > using to
> > identify griseus vs hendersonii.
> >
> > If sub-specific names are an attempt to categorize geographic variation
> > then
> > you can't identify an individual bird to subspecies, with certainty,
> > without
> > knowing the geographic part, and in this instance it appears to be the
> > breeding geography that is crucial.
> >
> > Also a subspecies is almost by definition an intermediate, a
> > population/taxa
> > where there is at least the potential for gene flow from another
> > population/taxa
> > so I don't know if it makes sense to talk about intermediates between
> > subspecies.
> > If the 2 subspecies are in contact and producing first generation
> > offspring
> > than odds are that they have been in contact long enough to produce
> > multiple
> > generations of offspring and there would be no difference between
> > variation
> > and intergradation.
> >
> > Using plumage and/or morphology alone to identify subspecies easily
leads
> > to a catch 22, especially when the forms are clinal as may be the case
> > here
> > with hendersonii and griseus blending into each other east to west (not
> > sure where caurinus fits in though).
> >
> > Didn't someone say we would be moving on to shorebirds in response to
> > frustration over gulls a little while back?
> >
> > Matt
> >
> >
> > Matt Sharp
> > Collection Manager
> > VIREO/ANS
> > 1900 Benjamin Franklin Pkwy.
> > Philadelphia PA 19103
> > http://vireo.acnatsci.org
> > (tel.) 215-299-1069
> > (fax) 215-299-1182
> >
> >
> > Join or Leave BIRDWG01: http://listserv.arizona.edu/cgi-
> > bin/wa?SUBED1=birdwg01
> >
> > Archives: http://listserv.arizona.edu/archives/birdwg01.html
> >
> > --
> > No virus found in this incoming message.
> > Checked by AVG Anti-Virus.
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> >
>
> --
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> Checked by AVG Anti-Virus.
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>
>
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Subject: RFI; Brewster's Warbler types ratio
From: Gary l Felton <gljeinwv(AT)JUNO.COM>
Date: 2 Jun 2005 2:41pm
I've seen three Brewster's Warblers in this general area, two in WV and
one in
an adjacent county in Md. All three were second-generation Brewster's.
I'm
curious if this is just pure co-incidence, or if second-generation birds
are the
ones that are most likely to be encountered during the beginning stages
of GWWA
displacement by BWWA. Can anyone shed some light on this?
Gary Felton
Kingwood, WV
GLJEINWV(AT)JUNO.COM
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Subject: How difficult, really, are the wood-pewees?
From: Ted Floyd <tedfloyd(AT)ABA.ORG>
Date: 3 Jun 2005 4:52am
Hello, birders.
First things first: I'm NOT about to claim that silent Eastern and
Western Wood-Pewees can be separated in the field. I do, however, wonder
if we've been going about wood-pewee identification the wrong way. I'll
outline my thinking as follows:
1. The basic treatment of the problem in the standard field guides.
2a. Some general observations of mine from the past several weeks.
2b. Specific comments about a problematic wood-pewee from last week.
3. A little bit of philosophizing about "problem" taxa in general.
Here goes!
1. The basic treatment of the problem in the standard field guides.
Certainly, the conventional wisdom is that the two wood-pewees are
"difficult" or "impossible" to separate in the field.
For example, Kenn Kaufman, in his influential Peterson Field Guide to
Advanced Birding (1990) says of the wood-pewees that it is "probably
impossible to distinguish them with certainty in the field by sight
alone." Kaufman's treatment goes on to discuss some fuzzy, subjective,
average characters that certainly seem to point toward difficulty, to
say the least, in the matter of sight indentification of the
wood-pewees.
A dozen years later, the 4th edition of the National Geographic Guide
(2002) was saying pretty much the same thing: sight identification is
very difficult, and, sure enough, the illustrations of the two species
look just about identical.
Now, enter the Sibley Guide (2000), which calls the two species
"essential identical" and "usually distinguishable only by voice". So
far, so good. But here's the curious part: The Sibley Guide also
enumerates a whole battery of characters that separate the two, among
them (1) overall coloration, (2) extent of greenish on the back, (3)
color of the breast-band, (4) extent of the breast-band, (5)
color/pattern of the undertail coverts, (6) color of the lower mandible,
(7) tail lengh, (8) wing length, (9) wing-bar color, (10) wing-bar
contrast, and (11) wing-bar thickness. And I may have missed a few.
Quick!--Can you rattle off as many differences between Gray-cheeked and
Swainson's Thrushes? Between Cassin's and Blue-headed Vireos? (I'll
return to vireos and thrushes later on, by the way.)
To be sure, the Sibley Guide emphasizes variation in all of these
characters, but I, for one, am still left with the impression that we
have a fair bit of field material to work with here. Other advanced
treatments are similar. Thus, works such as the Pyle manual and the BNA
accounts give us the following: (1) lots of "field marks", (2) lots of
variation, and (3) the caveat about field identification. Statistically
speaking: There's a lot of "noise" associated with any given character;
but do the characters add up to transmit a reliable "signal", i.e.,
sight identification as one species or the other? After all, that's how
we separate the tringine sandpipers from one another, and also the
calidrine sandpipers from one another. (And I'll return to these two
taxa later on, also.)
2a. Some general observations of mine from the past several weeks.
I've had the opportunity to observe both wood-pewee species these past
several weeks: Eastern Wood-Pewees in eastern Michigan; Western
Wood-Pewees in the eastern foothills of the Rocky Mountains in Colorado.
On *all* birds, I've been able to discern one or more of the various
distinguishing characteristics listed in Sibley (and/or in other
resources). On many birds, I've been able to discern as many as 6 or 7
of the characters. (Also, I should point out that I haven't been able to
do anything with tail length and wing length.) Almost always, the
field-discernible characters have been "right", too. In Michigan: pale,
greenish pewees with conspicuous wing bars; diffuse,
green/yellow-tinged, broken-down-the-middle breast patches; weakly
patterned undertail coverts; and orangish lower mandibles; etc. In
Colorado: darker, brownish-gray pewees with less-conspicuous wing bars;
solid, brown-gray breast patches; splotchier undertail coverts; and
less-orangish lower mandibles; etc.
Now, I should definitely concede the problem of bias here: I'm looking
at presumptive Easterns "knowing" what they're supposed to look like,
and I'm looking at presumptive Westerns also "knowing" what they're
supposed to look like. That said, I have really been struck by
consistent differences between wood-pewees in Michigan and Colorado. The
biggest difference, I have to say, and it's one I've noticed for many
years, is the overall color and brightness of the two species. Westerns
really look -sordidulus- to me, and Easterns -virens-. Sometimes, those
Latin names actually make sense... Admittedly, color and brightness are
subjective, "soft" field marks.
2b. Specific comments about a problematic wood-pewee from last week.
This past Saturday, 28 May 2005, I was out on the plains of eastern
Colorado. Good place for eastern strays. Good time of year for eastern
strays. Best of all: Many of my companions were casual birders, which I
don't intend in the least as a put-down. In fact, casual birders tend to
ask great questions, the sorts of questions that make us look at old ID
problems in brand-new ways. (Years ago, for example, a casual birder
called to my attention an uncommon Nevada "Black-and-white Warbler" that
was actually a rare Nevada Least Flycatcher; never mind why she thought
it was a Black-and-white Warbler, but her "mistake" got me to thinking
about empid ID in a new and valid way.)
Anyhow, we were working through a handful of Contopus flycatchers (there
was an Olive-sided in the mix), and one of the casual birders complained
that nothing I was saying made any sense for "THAT bird"--which I
finally looked at and which looked spot-on for Eastern Wood-Pewee. What
struck the beginners--and me, too--was how different the presumptive
Eastern looked from its companion Western. We worked through Sibley, and
everything added up: Overall color and tone, wing bars, breast patch,
undertail coverts, lower mandible, etc. (I silently pondered differences
in feather age/wear, but that seemed to be a dead-end; I'm pretty sure I
was working with birds in similar conditions of feather age/wear.)
We never heard the presumptive Eastern call. And note to any Colorado
Bird Records Committee members who may be out there: No, I'm not
claiming this as an ironclad sight-ID record for Colorado. At the same
time, I walked away from this bird, thinking two things: (1) wood-pewees
sure look different from one another; and (2) if the differences line up
across the species boundaries, which I am increasingly persuaded of,
then the birds just not all that hard. The big problem, of course, is
that so much of this is inferential. The ultimate affirmation, needless
to say, would've been for the bird to have said "peeeeuhweeeee,
peeeeewee". But that didn't happen.
3. A little bit of philosophizing about "problem" taxa in general.
Something that interests me is which taxa are considered "difficult" or
even "impossible" and which ones are not. There's a large amount of
cultural bias that goes into these assessments, in my opinion. First, we
learn that certain taxa can or cannot be mastered in the field, and it
becomes difficult to "unlearn" these lessons. This may be the case, for
example, with the Empidonax flycatchers, which, I am finding, are easier
for me to ID by sight than is the case with certain vireos or Catharus
thrushes. Actually, let me word that more modestly, and accurately: I'm
having many problems with certain vireos and Catharus thrushes! Second,
there are the taxa that *really* are hard but that we *really* have
mastered, e.g., yellowlegs and peeps. We have a solid grasp of the 10ish
characters that add up to separation of the problem species, and with
these taxa many of us are consistently correct in our identification at
the species level. Third, naturally and pragmatically, we tend toward ID
problems that involve sympatric rather than allopatric species pairs.
All of us can think of someone who has Northwestern Crow on his life
list, but who wouldn't have the foggiest clue how to recognize, say, a
stray Pygmy Nuthatch in a flock of Brown-headeds (far-fetched, but you
catch my drift). Fourth, even though the vast majority of birders are
too visual and not aural enough, there are certain taxa that invite the
voice-by-ID-only approach. Examples include empids, wills, and dows.
And I wonder if these lessons apply to the wood-pewees. First, I don't
take it as axiomatic that they're impossible or even all that difficult.
(But I don't know; see opening sentence.) Second, even if the
wood-pewees are legitimately hard, I'm not convinced that they're
impossible; hey, if the larophiles can attach a name to every worn large
white-headed gull, who's to stop me from trying to tackle the
wood-pewees? Third, I wonder if pewees have been neglected for the
reason that, >99% of the time, you're presumably dealing with one
species or the other. Fourth, there's the problem of the auditory
default: In the case of pewees, why bother to look, when you can just
listen?
Thanks, if you've gotten this far, for your time.
----------------------------
Ted Floyd
Editor,
Birding
American Birding Association
P.O. Box 7974
Boulder, Colorado 80306-7974
303-444-6363
tedfloyd(AT)aba.org
Please visit the website of the
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Subject: Re: Mystery Gull - Ponce Inlet
From: Keith Arnold <kaarnold(AT)TAMU.EDU>
Date: 3 Jun 2005 8:00am
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Larry, Martin, et al.
I think we are all too quick to assume a "mental concept" for a species
which does not account for the tremendouos individual variation one find
in many species, especially gulls. When I came to A&M, I discovered a
specimen labelled as "Larus marinus", a species not recorded [at that
time] in Texas and one I had not seen in anumber of years; also, it was
in 1st winter plumage and that didn't seem to fit textbook descriptions.
So, I sent the bird off to Bud Tordoff, then at the University of
Michigan Museum of Zoology: his ID - a Herring Gull with an unusually
large and massive bill, much like a Great Black-backed! If that's not
enoung to convince you that we have much to learn about individual
variation, the TCWC also has a female Glaucous Gull that's MUCH smaller
than the "typical" bird of that species.
Keith Arnold
WFSC TAMU
College Station
>>> Larry Manfredi <birderlm(AT)BELLSOUTH.NET> 6/2/2005 7:25:31 AM >>>
It is possible that it is a Herring Gull but how can you account for
the
small size? Herring Gulls are larger than Lesser Black-backed Gulls
and
Ring-billed Gulls are smaller than Lesser Black-backed Gulls, Bob said
the
bird was smaller than a Lesser Black-backed Gull. Of course it could
be a
runt Herring Gull but it would have to be a pretty small runt pretty
far
outside the range of a normal Herring Gull. The other point is that on
my
computer screen the eye of the bird is dark not yellow.
Another point that I would like to make is that my first impression and
what
Dexter thought, is that it is a Ring-billed Gull regardless of what
the
plumage looks like. To me it has more of the "Jizz" for a Ring-billed
than
a Herring Gull.
Larry Manfredi
P.S. As I am finishing this up Bob is telling us that the bird was the
same
size as a Lesser Black-backed Gull, what's up with that Bob? How is
this
going to hold up in a court of Law??? Below is what you wrote
yesterday
Bob!!
Size was just a tad smaller than Lesser Black-backed, which was seen
nearby
by Dex and Alex,
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