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ID-FRONTIERS for June 5-11, 2005
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Messages are displayed in the order they were received.
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| Subject | From | Date | Time |
| Hybrid Tern | Trevor Hardaker - ZE | Mon, 6 Jun 2005 | 1:10pm |
| Paul R Wood/UK/TLS/PwC is out of the office. | Paul Wood | Mon, 6 Jun 2005 | 1:23pm |
| Re: Hybrid Tern | Laurent Raty | Mon, 6 Jun 2005 | 2:59pm |
| RE : Hybrid Tern | =?iso-8859-1?Q?Pierr | Tue, 7 Jun 2005 | 12:32am |
| Re: RE : Hybrid Tern | Trevor Hardaker - ZE | Tue, 7 Jun 2005 | 10:04am |
| Just as follow up to the MOWA x COYE | Bill Elrick | Tue, 7 Jun 2005 | 11:03am |
| Arizona Gull 5/26/05 | Mark Stevenson | Wed, 8 Jun 2005 | 9:38am |
| Re: Arizona Gull 5/26/05 | Phillip Pickering | Wed, 8 Jun 2005 | 10:09am |
| Re: Arizona Gull 5/26/05 | Phillip Pickering | Wed, 8 Jun 2005 | 10:35am |
| Re: Arizona Gull 5/26/05 | Dick Newell | Wed, 8 Jun 2005 | 12:23pm |
| Subspecies | sgmlod(AT)AOL.COM | Wed, 8 Jun 2005 | 1:12pm |
| Re: Arizona Gull 5/26/05 | Phillip Pickering | Wed, 8 Jun 2005 | 1:49pm |
| Re: Subspecies | Laurent Raty | Wed, 8 Jun 2005 | 3:54pm |
| Re: Subspecies | Joseph Morlan | Wed, 8 Jun 2005 | 9:04pm |
| Re: Subspecies | Dick Newell | Thu, 9 Jun 2005 | 12:37am |
| Subspecies and AOU Check-list | Jean Iron | Thu, 9 Jun 2005 | 6:30am |
| Re: Subspecies | sgmlod(AT)AOL.COM | Thu, 9 Jun 2005 | 8:08am |
| Article on subspecies | sgmlod(AT)AOL.COM | Thu, 9 Jun 2005 | 8:11am |
| Re: Subspecies and AOU Check-list | Joseph Morlan | Thu, 9 Jun 2005 | 8:55am |
| Re: Subspecies and AOU Check-list | Jean Iron | Thu, 9 Jun 2005 | 9:10am |
| Re: Subspecies | Joseph Morlan | Thu, 9 Jun 2005 | 9:37am |
| Re: Subspecies and AOU Check-list | Joseph Morlan | Thu, 9 Jun 2005 | 9:43am |
| Re: Subspecies and AOU Check-list | sgmlod(AT)AOL.COM | Thu, 9 Jun 2005 | 10:32am |
| Re: Subspecies and AOU Check-list | Dick Newell | Thu, 9 Jun 2005 | 10:41am |
| Re: Subspecies | sgmlod(AT)AOL.COM | Thu, 9 Jun 2005 | 10:49am |
| Help with small Calidrid | Don Roberson | Thu, 9 Jun 2005 | 5:59pm |
| Re: Help with small Calidrid | Julian Hough | Thu, 9 Jun 2005 | 6:38pm |
| Re: Subspecies | Sam Stuart | Thu, 9 Jun 2005 | 8:41pm |
| Re: Help with small Calidrid | Lethaby, Nick | Thu, 9 Jun 2005 | 9:44pm |
| Re: Help with small Calidrid | Thomas J. Dunkerton | Fri, 10 Jun 2005 | 5:20am |
| Re: Subspecies | Alvaro Jaramillo | Fri, 10 Jun 2005 | 10:27am |
| Re: Subspecies | GreatGrayOwl(AT)AOL.COM | Fri, 10 Jun 2005 | 7:23pm |
| Another Glossy Ibis? | Cliff and Lisa Weiss | Sat, 11 Jun 2005 | 7:40pm |
|
To use email addresses replace '(AT)' with '@'.
This is done to confuse the spam 'bots.
|
[ << | >> | ^^ ]
Subject: Hybrid Tern
From: Trevor Hardaker - ZEST for BIRDS <trevor(AT)ZESTFORBIRDS.CO.ZA>
Date: 6 Jun 2005 1:10pm
Hi All,
Sorry for any cross posting.
Since Lesser Crested Tern and Sandwich Tern have reasonably cosmopolitan
distributions throughout the world, we thought some of you might be
interested in this.
We have added some photos of a hybrid Lesser Crested x Sandwich Tern to the
"features" section on our website at www.zestforbirds.co.za that were taken
recently in the Eastern Cape. For all intents and purposes, the bird
resembles a Lesser Crested Tern except in that it shows a pink flush to the
breast.
Hope this is of some use to some of you.
Kind Regards
Trevor
--------------------------------------------------------
Trevor Hardaker and John Graham
ZEST for BIRDS
Cape Town, South Africa
Website: www.zestforbirds.co.za
--------------------------------------------------------
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Subject: Paul R Wood/UK/TLS/PwC is out of the office.
From: Paul Wood <paul.r.wood(AT)uk.pwc.com>
Date: 6 Jun 2005 1:23pm
I will be out of the office from 04/06/2005 until 13/06/2005.
I am away from the office from close of business on Friday 3 June 2005
until Monday 13 June 2005. I will not have access to my e-mail during this
time and will respond to your message when I return to the office.
_________________________________________________________________
The information transmitted is intended only for the person or entity to
which it is addressed and may contain confidential and/or privileged
material. Any review, retransmission, dissemination or other use of, or
taking of any action in reliance upon, this information by persons or
entities other than the intended recipient is prohibited. If you received
this in error, please contact the sender and delete the material from any
computer.
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Subject: Re: Hybrid Tern
From: Laurent Raty <l.raty(AT)SKYNET.BE>
Date: 6 Jun 2005 2:59pm
Hi Trevor,
The parent bird on the pictures here :
http://www.surfbirds.com/cgi-bin/gallery/display.cgi?gallery=gallery11&start=587
...is the same individual (green over yellow on the left tarsus, white on
the right tarsus, metal on the right tibia).
It's not a bird from Banc d'Arguin in Mauritania (as your webpage
indicates), but from Banc d'Arguin in France. Last time I heard, this bird
was unidentified and of unknown parentage - but it had been DNA-sampled,
so things may have changed.
Cheers,
Laurent -
Laurent Raty
Brussels, Belgium
l.raty(AT)skynet.be
----- Original Message -----
From: "Trevor Hardaker - ZEST for BIRDS" <trevor(AT)ZESTFORBIRDS.CO.ZA>
To: <BIRDWG01(AT)LISTSERV.ARIZONA.EDU>
Sent: Monday, June 06, 2005 22:09
Subject: [BIRDWG01] Hybrid Tern
> Hi All,
>
> Sorry for any cross posting.
>
> Since Lesser Crested Tern and Sandwich Tern have reasonably cosmopolitan
> distributions throughout the world, we thought some of you might be
> interested in this.
>
> We have added some photos of a hybrid Lesser Crested x Sandwich Tern to
> the "features" section on our website at www.zestforbirds.co.za that
> were taken recently in the Eastern Cape. For all intents and purposes,
> the bird resembles a Lesser Crested Tern except in that it shows a pink
> flush to the breast.
>
> Hope this is of some use to some of you.
>
> Kind Regards
> Trevor
> --------------------------------------------------------
> Trevor Hardaker and John Graham
> ZEST for BIRDS
> Cape Town, South Africa
> Website: www.zestforbirds.co.za
> --------------------------------------------------------
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Subject: RE : Hybrid Tern
From: =?iso-8859-1?Q?Pierre-Andr=E9_CROCHET?= <pierre-andre.crochet(AT)CEFE.CNRS.FR>
Date: 7 Jun 2005 12:32am
Dear all,
As Laurent rightly pointed out, this bird is NOT the offspring of a mixed
bengalensis X sandvicensis pair. It is a bird caught and ringed as an adult.
It's identity is unknown: it is most similar to bengalensis, but with a white
rump (pointing to elegans). It could conceivably be an atypical bengalensis
(with a whitish rump), an atypical elegans (with a shorter and paler bill than
usual, and a shorther crest; ok that's many atypical features...) or, perhaps
more likely a hybrid, but not necessarily with sandvicensis.
I still have the DNA samples on my desk, and I'm waiting for samples of pure
elegans and bengalensis to start the analyses. If somebody can help with elegans
feather or blood samples... Same with bengalensis, by the way...
All the best,
Pierre
PLEASE NOTE NEW EMAIL // ATTENTION NOUVELLE ADRESSE EMAIL
Pierre-André Crochet
CNRS-UMR 5175 Centre d'Ecologie Fonctionnelle et Evolutive
1919, route de Mende
34293 Montpellier cedex 5
France
tel: + 33 6 07 32 60 75 (mobile)
+ 33 4 67 61 32 98 (office)
fax: + 33 4 67 41 21 38
pierre-andre.crochet(AT)cefe.cnrs.fr
-----Message d'origine-----
De : NBHC ID-FRONTIERS Frontiers of Field Identification
[mailto:BIRDWG01(AT)LISTSERV.ARIZONA.EDU] De la part de Laurent Raty
Envoyé : 06 June 2005 23:55
À : BIRDWG01(AT)LISTSERV.ARIZONA.EDU
Objet : Re: [BIRDWG01] Hybrid Tern
Hi Trevor,
The parent bird on the pictures here :
http://www.surfbirds.com/cgi-bin/gallery/display.cgi?gallery=gallery11&start=587
...is the same individual (green over yellow on the left tarsus, white on
the right tarsus, metal on the right tibia).
It's not a bird from Banc d'Arguin in Mauritania (as your webpage
indicates), but from Banc d'Arguin in France. Last time I heard, this bird
was unidentified and of unknown parentage - but it had been DNA-sampled,
so things may have changed.
Cheers,
Laurent -
Laurent Raty
Brussels, Belgium
l.raty(AT)skynet.be
----- Original Message -----
From: "Trevor Hardaker - ZEST for BIRDS" <trevor(AT)ZESTFORBIRDS.CO.ZA>
To: <BIRDWG01(AT)LISTSERV.ARIZONA.EDU>
Sent: Monday, June 06, 2005 22:09
Subject: [BIRDWG01] Hybrid Tern
> Hi All,
>
> Sorry for any cross posting.
>
> Since Lesser Crested Tern and Sandwich Tern have reasonably cosmopolitan
> distributions throughout the world, we thought some of you might be
> interested in this.
>
> We have added some photos of a hybrid Lesser Crested x Sandwich Tern to
> the "features" section on our website at www.zestforbirds.co.za that
> were taken recently in the Eastern Cape. For all intents and purposes,
> the bird resembles a Lesser Crested Tern except in that it shows a pink
> flush to the breast.
>
> Hope this is of some use to some of you.
>
> Kind Regards
> Trevor
> --------------------------------------------------------
> Trevor Hardaker and John Graham
> ZEST for BIRDS
> Cape Town, South Africa
> Website: www.zestforbirds.co.za
> --------------------------------------------------------
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--
passerelle antivirus du campus CNRS de Montpellier
--
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[ << | >> | ^^ ]
Subject: Re: RE : Hybrid Tern
From: Trevor Hardaker - ZEST for BIRDS <trevor(AT)ZESTFORBIRDS.CO.ZA>
Date: 7 Jun 2005 10:04am
Hi Laurent, Pierre and others,
Thanks for your informative answers. It will teach me to check my facts next
time and not just assume that the information I receive is correct!!
The information I received was via the South African Ringing Unit (SAFRING)
who apparently received their information from somebody in Europe!!
I would be very interested to hear what the final outcome is with respect to
the id of this bird. Please keep me informed.
Thanks and regards
Trevor
--------------------------------------------------------
Trevor Hardaker and John Graham
ZEST for BIRDS
Cape Town, South Africa
Website: www.zestforbirds.co.za
--------------------------------------------------------
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Subject: Just as follow up to the MOWA x COYE
From: Bill Elrick <belrick(AT)OPTONLINE.NET>
Date: 7 Jun 2005 11:03am
Sorry for X posting
I had only two replies to my question if this bird was a MOWA {Mourning
warbler) X COYE{Common Yellow-throat} and I will summaries those below.
Photos first here
>>
http://www.scottelowitzphotography.com/gallery/misc/S0I7219mowa?x=70&y=7
8&searchstring=Mourning+Warbler<<
>>
1 snip >> You may already know of a paper by Tony Bledsoe here
>>http://elibrary.unm.edu/sora/Wilson/v100n01/p0001-p0008.pdf<<, that
describes a MOWA x COYE hybrid. That bird is a fall specimen, so not
directly comparable to the NJ bird, but close enough. My quick reaction
is that the NJ bird is a hybrid of those two. The vague black mask and
whitish throat are consistent with the CT specimen.<<
2 snip >> I would go with a hybrid origin for this bird. Mourning
Warblers have shorter tails, and longer uppertail coverts than this
bird, your bird shows a tail/covert pattern much more like McGillvray's
Warbler! As well, the Buffy wash to the flanks, and throat features all
suggest that this is not a pure Mourning, but one mixed with Common
Yellowthroat. Also since it was singing you know it's a male, that
simplifies things.<<
So that's it download the PDF file look at the drawings and come to your
own conclusions and if anyone else has anything to add please do so.
Some extra info.
This bird was feeding very high in the trees most of the time and
although that's not common for a COYE {Common Yellow-throat} it is
uncommon for a MOWA {Mourning warbler) so it was an odd bird straight
off. This however does not make it one or the other. Bruce McWhorter and
others heard and recorded the bird sing a complete and accurate COYE
song so this was when we started wondering about its genetics.
Bill Elrick
West Milford
NJ
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Subject: Arizona Gull 5/26/05
From: Mark Stevenson <drbrdr(AT)WORLDNET.ATT.NET>
Date: 8 Jun 2005 9:38am
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Greetings larophiles,
Living in a landlocked state, I don't get a lot of gulling in (and =
might even be classified as a larophobe, larignoramus or mislarist, if =
you'll pardon the neologisms). On May 26, 2005 a large gull dropped in =
at Willcox, AZ long enough to be seen and photographed by a few. So far, =
there is sub-total consensus on the identification of the bird, with =
opinions ranging from Glaucous-winged to Thayer's.
Photos of the bird appear on the AZ Field Ornithologists web page =
at:
http://www.azfo.org/gallery/willcox_gull.html
Unfortunately, no spread-wing photos were obtained.
Thanks in advance for your comments.
Mark Stevenson
Tucson, AZ
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Subject: Re: Arizona Gull 5/26/05
From: Phillip Pickering <philliplc(AT)HARBORSIDE.COM>
Date: 8 Jun 2005 10:09am
http://www.azfo.org/gallery/willcox_gull.html
Apparent structure/jizz varies between photos but overall appears
somewhat large-billed, chunky, long-legged, and short-winged
for Thayer's. Structurally it is closer to Glaucous-winged, however
primaries/tail appear way too dark for a pure G-w, particularly
in this condition, and even a bit dark for a Western x G-w with
mantle shade this pale. Skull shape has Herring-like aspects,
so for whatever it's worth guessing at these things, best fit seems
to be Herring x G-w.
Cheers,
Phil Pickering
Lincoln City, Oregon
philliplc(AT)harborside.com
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Subject: Re: Arizona Gull 5/26/05
From: Phillip Pickering <philliplc(AT)HARBORSIDE.COM>
Date: 8 Jun 2005 10:35am
> http://www.azfo.org/gallery/willcox_gull.html
Should add that I rarely see Herrings this late in the year and given
the bird's state I'm not sure it couldn't be a pure Herring. Also P9
seems evenly dark accross both webs in the bottom photo, which
would support a part/most/all Herring vs. either Thayer's or G-w.
Cheers,
Phil
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Subject: Re: Arizona Gull 5/26/05
From: Dick Newell <dick.newell(AT)ZEN.CO.UK>
Date: 8 Jun 2005 12:23pm
On 8/6/05 18:09, "Phillip Pickering" <philliplc(AT)HARBORSIDE.COM> wrote:
> http://www.azfo.org/gallery/willcox_gull.html
>
> Apparent structure/jizz varies between photos but overall appears
> somewhat large-billed, chunky, long-legged, and short-winged
> for Thayer's.
Well,
Large billed because the head feather's are worn
Chunky - Thayer's can look chunky
Long-legged - it is standing on tip toe in one picture, but looks rather
short-legged in another.
Short-winged - again wear, besides it is riding very tail-high in the water.
It may not be a 3CY Thayer's, but I wouldn't confidently say it's not.
One might expect a Herring Gull of this age to have a pale eye and it
doesn't look ugly enough for Glaucous-winged, in one shot it looks quite
cute - but that's subjective.
Have I mis-identified this bleached bird?:
http://www.magikbirds.com/image.asp?title_id=56
Dick Newell
Cambridge, UK
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Subject: Subspecies
From: sgmlod(AT)AOL.COM
Date: 8 Jun 2005 1:12pm
----INCLUDING text/plain MIME SECTION----
Greetings All
Though perhaps a bit off topic, the definition of subspecies is applicable to
much of what we discuss here. Early ornithologists often ascribed subspecific
status to any local variation. Indeed, many subspecies were "intermediates." At
one point, this led to the AOU essentially abandoning the subspecies concept.
Certainly, using "subspecies" to define clinal variations between populations is
of limited utility and often confusing, for where does one draw the line in
such circumstances?
However, if I am not mistaken, a much more refined definition of subspecies has
come into general use. The first time I saw this was in a paper by Michael
Patten and another author on Sage Sparrow races. I am not sure if they were the
first to use this or if the definition was already in use.
Essentially, a subspecies is a population in which 75% of its individuals are
reliably separable from 99% of another population of the same species. This
makes subspecies a very specific term (pun partially intended) and one that does
not describe intermediate populations but, in general, populations that have
travelled part of the way towards full speciation. These populations tend to
show differences which are "step-offs" from other populations rather than
gradual clinal variation. They act somewhat as separate units from other
populations, often filling different niches and having differing ecologies.
Which populations truly deserve the designation of "subspecies" seems to be in a
state of flux, as the older designations (often based on clinal variations) are
re-examined.
Cheers
Steven Mlodinow
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Subject: Re: Arizona Gull 5/26/05
From: Phillip Pickering <philliplc(AT)HARBORSIDE.COM>
Date: 8 Jun 2005 1:49pm
> Well,
> Large billed because the head feather's are worn
> Chunky - Thayer's can look chunky
> Long-legged - it is standing on tip toe in one picture, but looks rather
> short-legged in another.
> Short-winged - again wear, besides it is riding very tail-high in the
water.
I'm looking more at bill thickness than length, particularly in the bottom
shot. Even the most misleadingly compressed telephoto shots of
Thayer's usually don't give the thick-billed small-eyed jizz apparent in
this shot. I suppose it's possible this is an exceptional extreme, but
it doesn't look that way to me. Also Thayer's can look a little barrel-
chested, but typically not quite this thick-reared. Seems like there's
too much 'bird' behind the legs in these shots. Leg length is too subjective
I guess, but even accounting for extreme wear still looks short-winged
to me.
> It may not be a 3CY Thayer's, but I wouldn't confidently say it's not.
> One might expect a Herring Gull of this age to have a pale eye
Correct me if I'm missing something, but I think this is 2CY - coverts
are mostly strings in May, bill all dark. It does appear to have developed
apical spots, but that could be due to extreme P tip wear. 2CY G-w can
show this amount of adult gray in the mantle in late May/June, not sure
about Herring or Thayer's.
> doesn't look ugly enough for Glaucous-winged, in one shot it looks quite
> cute - but that's subjective.
Small female presumed Herring x G-w can look sort of cute and Thayer's-
like (unfortunately).
> Have I mis-identified this bleached bird?:
> http://www.magikbirds.com/image.asp?title_id=56
Possibly. Primaries/tertials seem uncomfortably uniformly dark to
me, and inner webs of outer P's appear somewhat dusky and low
contrast. Apparent skull shape with crown feathers flattened
seems more Herring-like. Eye a little beady and centralized.
Wing base seems proportionately a little broad. Location is
in the heart of hybrid land, so hard to be confident on this
one.
Cheers,
Phil
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Subject: Re: Subspecies
From: Laurent Raty <l.raty(AT)SKYNET.BE>
Date: 8 Jun 2005 3:54pm
Hi Steven,
> Essentially, a subspecies is a population in which 75%
> of its individuals are reliably separable from 99% of
> another population of the same species. This makes
> subspecies a very specific term (pun partially intended)
> and one that does not describe intermediate populations but,
> in general, populations that have travelled part of the way
> towards full speciation. These populations tend to show
> differences which are "step-offs" from other populations
> rather than gradual clinal variation.
Well... I've read Patten & Unitt's paper too, but I've always had problems
with this particular point.
Imagine a perfectly gradual cline. Assume that all along this cline, local
variation is small as compared to the whole variation represented by the
cline. Now, cut this cline in two. If local variance is small enough,
unID'able individuals will only occur in the area very close to the cut;
this area will be small as compared to the two cline segments; and you
will clearly be able to ID a very high proportion of the individuals of
the two groups.
I just fail to see how simply setting a percentage of ID'able individuals
could ensure that subspecies limits are placed on discontinuities, rather
than more-or-less arbitrarily in the middle of a clinal variation, as in
the example above.
Cheers,
Laurent -
Laurent Raty
Brussels, Belgium
l.raty(AT)skynet.be
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Subject: Re: Subspecies
From: Joseph Morlan <jmorlan(AT)CCSF.ORG>
Date: 8 Jun 2005 9:04pm
On Wed, 8 Jun 2005 16:12:53 -0400, sgmlod(AT)AOL.COM wrote:
>Essentially, a subspecies is a population in which 75% of its individuals are
reliably separable from 99% of another population of the same species.
This is the old 75% rule proposed originally by Amadon:
Amadon, D. 1949. The seventy-five percent rule for subspecies. Condor 51:
250-258.
However, it should be noted that this rule has seldom been systematically
applied for a variety of reasons.
Separable how? The more characters one assesses the greater the
differences one may detect. Some characters may be very obvious, while
other are extremely obscure. One taxonomist may note some differences,
another taxonomist will find those differences to be caused by wear or age
or some other factors not considered by the original taxonomists.
Subspecies are simply a way of describing geographic variation using
nomenclature. The validity of any subspecies is inevitably a matter of
opinion and difficult to test via any rigorous set of criteria.
>This makes subspecies a very specific term (pun partially intended) and one
that does not describe intermediate populations but, in general, populations
that have travelled part of the way towards full speciation. These populations
tend to show differences which are "step-offs" from other populations rather
than gradual clinal variation. They act somewhat as separate units from other
populations, often filling different niches and having differing ecologies.
I must disagree with the view that subspecies have traveled part of the way
towards full species. Subspecies are not a unit of evolution. They are
simply types of geographic variation in polytypic species. Unless these
subspecific populations become geographically isolated, they have little if
any potential to evolve into full species.
Also I see no reason why subspecies need to fill different niches or have
differing ecologies. By definition, species fill a unique niche in nature,
but the same cannot be said of subspecies.
--
Joseph Morlan, Pacifica, CA 94044 jmorlan (at) ccsf.org
Fall Birding Classes start Sep 13 http://fog.ccsf.edu/~jmorlan/
California Bird Records Committee http://www.wfo-cbrc.org/cbrc/
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Subject: Re: Subspecies
From: Dick Newell <dick.newell(AT)ZEN.CO.UK>
Date: 9 Jun 2005 12:37am
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Debates about subspecies definitions will go on for ever while a rigid,
discrete system of nomenclature is incompatible with what is going on in th=
e
real world. If engineers wish to represent a smooth continuous function,
they may well choose to do that by a series of point coordinates, with
smooth interpolation in between. The equivalent representation of a cline,
which may be 2 dimensional, and even multi-valued in the case of a
ring-species, would be to choose an appropriate set of locations, and a
small region around them, and use individuals from each location to
represent, not a whole population, but the taxon at each location. The whol=
e
species is then represented by a surface, defined by discrete points, with
some form of interpolation between the points. If the nomenclature could be
made numeric (say a number of numeric parameters, perhaps with their local
variances), then the interpolation might be more straight forward. So when =
I
go out bird watching, I=B9m not just looking at a Chaffinch, but I am looking
at a Chaffinch (3.2,2.4,5.7) which is different from a Chaffinch 100 miles
away which might be Chaffinch (3.3,2.3,5.8) - maybe this is getting silly!
But seriously, that=B9s how complicated it really is.
Dick Newell
Cambridge, UK
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Subject: Subspecies and AOU Check-list
From: Jean Iron <jeaniron(AT)SYMPATICO.CA>
Date: 9 Jun 2005 6:30am
In opening the discussion on subspecies* (races), Steven Mlodinow stated,
"At one point, this led to the AOU essentially abandoning the subspecies
concept."
I've been wondering about the accuracy of the above statement. The most
recent seventh edition of the AOU Check-list (1998) on page xii says, "As
in the sixth edition, for reasons of expediency, the Committee reluctantly
excluded treatment of subspecies in the current volume. Their omission
should not be interpreted as a devaluation of the importance of that
taxonomic rank. To the contrary, the Committee strongly and unanimously
continues to endorse the biological reality and practical utility of
subspecies. Subspecies names denote geographic segments of a species'
populations that differ abruptly and discretly in morphology or coloration;
these differences often correspond with differences in behavior and
habitat. Such populations also are 'species-the-making' and therefore
constitute a significant element of newly evolving biodiversity. The
Committee's endorsement of subspecies as entities worthy of scientific
inquiry carries with it our realization that an uncertain number of
currently recognized subspecies, especially those formally named early in
the century, probably cannot be validated by rigorous modern techniques.
The opposite is also true; after careful study an unknown number of present
subspecies probably will be unmasked as cryptic biological species. This
point further emphasizes the important role of this taxonomic rank in
calling attention to examples of avian diversity deserving additional
investigation."
I understand that the next AOU Check-list in about 2010 or later will
include well-marked subspecies that are allopatric and those joined by
steep clines. It will much reduce the number of poorly-marked and broadly
clinal subspecies described in the AOU Check-list (1957), which was the
last to name subspecies.
*Subspecies and race are synonymous. Most North American ornithologists and
birders prefer using the term subspecies whereas the term race is preferred
in Britain and Ireland.
Ron Pittaway
Minden and Toronto, Ontario
jeaniron(AT)sympatico.ca
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Subject: Re: Subspecies
From: sgmlod(AT)AOL.COM
Date: 9 Jun 2005 8:08am
----INCLUDING text/plain MIME SECTION----
Greetings All
Indeed, many subspecies (as defined by Amadon, not the vast array found in the
1957 AOU check-list) probably have travelled part way towards being separate
species. Many of these populations are thought to have been separated by
previous climatic events, such as iceages, and then come into contact again at a
later date. They've differentiated enough to be somewhat different but not
enough to be fully reproductively isolated. The Fox Sparrows are a great
example. They occupy totally different niches in WA. Similarly, LB Sparrow and
Ipswich Sparrow (and Belding's) occupy very different niches from the main swarm
of Sav Sparrow races (which to most folks eyes would not meet Amadon's rules).
Yes there are exceptions. This is a sloppy business where no "rule" is going to
work, but I still think Amadon's rule forms a great starting base allowing for
scientific work to be done rather than willy-nilly "this population seems
different from that to me." Part of the reason we don't see
it applied much now is that there seems to virtually no work on subspecies
being done, unless its trying to discern if they are really separate species.
For subspecies representing step-clines, it is hard to imagine how they would
arise WITHOUT being geographically isolated at some point. For those
representing steady clines, few would meet Amadon's rule.
And there is no "rule" stating that species occupy separate niches. The rule,
currently, is that there is not significant gene flow. These are different
things, for two populations can be reproductively isolated and fill the same
niche. There is a tendency, over time, for this not to happen, because two
species trying to occupy the same niche will eventually lead to a "winner" and a
"loser" which is excluded.
Cheers
SteveM
-----Original Message-----
From: Joseph Morlan <jmorlan(AT)ccsf.org>
To: sgmlod(AT)AOL.COM
Cc: BIRDWG01(AT)LISTSERV.ARIZONA.EDU
Sent: Wed, 08 Jun 2005 21:06:09 -0700
Subject: Re: [BIRDWG01] Subspecies
On Wed, 8 Jun 2005 16:12:53 -0400, sgmlod(AT)AOL.COM wrote:
>Essentially, a subspecies is a population in which 75% of its individuals are
reliably separable from 99% of another population of the same species.
This is the old 75% rule proposed originally by Amadon:
Amadon, D. 1949. The seventy-five percent rule for subspecies. Condor 51:
250-258.
However, it should be noted that this rule has seldom been systematically
applied for a variety of reasons.
Separable how? The more characters one assesses the greater the
differences one may detect. Some characters may be very obvious, while
other are extremely obscure. One taxonomist may note some differences,
another taxonomist will find those differences to be caused by wear or age
or some other factors not considered by the original taxonomists.
Subspecies are simply a way of describing geographic variation using
nomenclature. The validity of any subspecies is inevitably a matter of
opinion and difficult to test via any rigorous set of criteria.
>This makes subspecies a very specific term (pun partially intended) and one
that does not describe intermediate populations but, in general, populations
that have travelled part of the way towards full speciation. These populations
tend to show differences which are "step-offs" from other populations rather
than gradual clinal variation. They act somewhat as separate units from other
populations, often filling different niches and having differing ecologies.
I must disagree with the view that subspecies have traveled part of the way
towards full species. Subspecies are not a unit of evolution. They are
simply types of geographic variation in polytypic species. Unless these
subspecific populations become geographically isolated, they have little if
any potential to evolve into full species.
Also I see no reason why subspecies need to fill different niches or have
differing ecologies. By definition, species fill a unique niche in nature,
but the same cannot be said of subspecies.
--
Joseph Morlan, Pacifica, CA 94044 jmorlan (at) ccsf.org
Fall Birding Classes start Sep 13 http://fog.ccsf.edu/~jmorlan/
California Bird Records Committee http://www.wfo-cbrc.org/cbrc/
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Subject: Article on subspecies
From: sgmlod(AT)AOL.COM
Date: 9 Jun 2005 8:11am
----INCLUDING text/plain MIME SECTION----
From Gjon Hazard
For an interesting discussion on aspects of the sub-species and species
question, see Van Remsen's overview article in the latest Auk (especially
"The 'Species' Problem" section therein).
Remsen, J. V., Jr. 2005. Pattern, process, and rigor meet classification.
Auk 122: 403-413.
Cheers,
-Gj
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Subject: Re: Subspecies and AOU Check-list
From: Joseph Morlan <jmorlan(AT)CCSF.ORG>
Date: 9 Jun 2005 8:55am
On Thu, 9 Jun 2005 09:28:00 -0400, Jean Iron <jeaniron(AT)SYMPATICO.CA> wrote:
>*Subspecies and race are synonymous.
Not exactly. There are many different types of races. Subspecies are
merely one of those types, the "geographic race."
>Most North American ornithologists and
>birders prefer using the term subspecies whereas the term race is preferred
>in Britain and Ireland.
--
Joseph Morlan, Pacifica, CA 94044 jmorlan (at) ccsf.org
Fall Birding Classes start Sep 13 http://fog.ccsf.edu/~jmorlan/
California Bird Records Committee http://www.wfo-cbrc.org/cbrc/
Join or Leave BIRDWG01: http://listserv.arizona.edu/cgi-bin/wa?SUBED1=birdwg01
Archives: http://listserv.arizona.edu/archives/birdwg01.html
[ << | >> | ^^ ]
Subject: Re: Subspecies and AOU Check-list
From: Jean Iron <jeaniron(AT)SYMPATICO.CA>
Date: 9 Jun 2005 9:10am
Hi Joe,
I disagree. In ornithology: subspecies, race, and geographic race all have
the same meaning. The term subspecies tends to be the formal name for the
concept.
Ron Pittaway
Minden and Toronto
jeaniron(AT)sympatico.ca
At 08:56 AM 6/9/2005 -0700, Joseph Morlan wrote:
>On Thu, 9 Jun 2005 09:28:00 -0400, Jean Iron <jeaniron(AT)SYMPATICO.CA> wrote:
>
> >*Subspecies and race are synonymous.
>
>Not exactly. There are many different types of races. Subspecies are
>merely one of those types, the "geographic race."
>
> >Most North American ornithologists and
> >birders prefer using the term subspecies whereas the term race is preferred
> >in Britain and Ireland.
>--
>Joseph Morlan, Pacifica, CA 94044 jmorlan (at) ccsf.org
>Fall Birding Classes start Sep 13 http://fog.ccsf.edu/~jmorlan/
>California Bird Records Committee http://www.wfo-cbrc.org/cbrc/
>
>
>Join or Leave BIRDWG01: http://listserv.arizona.edu/cgi-bin/wa?SUBED1=birdwg01
>
>Archives: http://listserv.arizona.edu/archives/birdwg01.html
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[ << | >> | ^^ ]
Subject: Re: Subspecies
From: Joseph Morlan <jmorlan(AT)CCSF.ORG>
Date: 9 Jun 2005 9:37am
On Thu, 9 Jun 2005 11:08:15 -0400, sgmlod(AT)AOL.COM wrote:
>Greetings All
>
>Indeed, many subspecies (as defined by Amadon, not the vast array found in the
1957 AOU check-list) probably have travelled part way towards being separate
species.
A colleague wrote privately, expressing my thoughts better than I did. He
wrote, "Subspecies are not necessarily destined to become a new species.
This is a big misunderstanding that people have, as if there is some drive
for species to be created, and subspecies are working their way up the
ladder to reach this goal. This may or may not happen, but clearly in birds
geographic isolation is a pre-requisite (other than in this ring species
they have "confirmed" on one of the Old World Warblers)."
>Many of these populations are thought to have been separated by previous
climatic events, such as iceages, and then come into contact again at a later
date. They've differentiated enough to be somewhat different but not enough to
be fully reproductively isolated. The Fox Sparrows are a great example. They
occupy totally different niches in WA. Similarly, LB Sparrow and Ipswich Sparrow
(and Belding's) occupy very different niches from the main swarm of Sav Sparrow
races (which to most folks eyes would not meet Amadon's rules). Yes there are
exceptions. This is a sloppy business where no "rule" is going to work, but I
still think Amadon's rule forms a great starting base allowing for scientific
work to be done rather than willy-nilly "this population seems different from
that to me." Part of the reason we don't see
> it applied much now is that there seems to virtually no work on subspecies
being done, unless its trying to discern if they are really separate species.
>
>For subspecies representing step-clines, it is hard to imagine how they would
arise WITHOUT being geographically isolated at some point. For those
representing steady clines, few would meet Amadon's rule.
Many populations at the extreme ends of a long cline easily meet Amadon's
rule without ever having been geographically isolated. Furthermore, I
think it's too easy to create "valid" subspecies using Amadon's 75% rule,
simply by multiplying the number of characters used to assess differences.
>And there is no "rule" stating that species occupy separate niches.
Mayr included it as part of his 1982 amended definition of biological
species: "A species is a reproductive community of populations
(reproductively isolated from others) that occupies a specific niche in
nature." (Mayr E. 1982. The Growth of Biological Thought. Harvard
University Press, Cambridge, Mass.)
It is a consequence of competitive exclusion which occurs when similar
species overlap. Thus each species occupies a unique niche in nature.
>The rule, currently, is that there is not significant gene flow. These are
different things, for two populations can be reproductively isolated and fill
the same niche.
Such populations, if they exist, would be extremely interesting to
evolutionary biologists because they would violate Gause's Law of
Competitive Exclusion. I am unaware of any examples of this which have
been exhaustively examined.
>There is a tendency, over time, for this not to happen, because two species
trying to occupy the same niche will eventually lead to a "winner" and a "loser"
which is excluded.
Agreed. Natural selection, as an evolutionary force, occurs only among
individuals which compete directly for limited resources. That normally
means individual members of the same species.
--
Joseph Morlan, Pacifica, CA 94044 jmorlan (at) ccsf.org
Fall Birding Classes start Sep 13 http://fog.ccsf.edu/~jmorlan/
California Bird Records Committee http://www.wfo-cbrc.org/cbrc/
Join or Leave BIRDWG01: http://listserv.arizona.edu/cgi-bin/wa?SUBED1=birdwg01
Archives: http://listserv.arizona.edu/archives/birdwg01.html
[ << | >> | ^^ ]
Subject: Re: Subspecies and AOU Check-list
From: Joseph Morlan <jmorlan(AT)CCSF.ORG>
Date: 9 Jun 2005 9:43am
On Thu, 9 Jun 2005 12:10:47 -0400, Jean Iron <jeaniron(AT)SYMPATICO.CA> wrote:
>I disagree. In ornithology: subspecies, race, and geographic race all have
>the same meaning. The term subspecies tends to be the formal name for the
>concept.
As a practical matter, in the context of ornithology, you are correct. But
when people discuss human races, or parasites with host races, they are not
talking about subspecies. Thus they are not exactly synonyms and that's
all I was trying to point out.
>At 08:56 AM 6/9/2005 -0700, Joseph Morlan wrote:
>>On Thu, 9 Jun 2005 09:28:00 -0400, Jean Iron <jeaniron(AT)SYMPATICO.CA> wrote:
>>
>> >*Subspecies and race are synonymous.
>>
>>Not exactly. There are many different types of races. Subspecies are
>>merely one of those types, the "geographic race."
>>
>> >Most North American ornithologists and
>> >birders prefer using the term subspecies whereas the term race is preferred
>> >in Britain and Ireland.
--
Joseph Morlan, Pacifica, CA 94044 jmorlan (at) ccsf.org
Fall Birding Classes start Sep 13 http://fog.ccsf.edu/~jmorlan/
California Bird Records Committee http://www.wfo-cbrc.org/cbrc/
Join or Leave BIRDWG01: http://listserv.arizona.edu/cgi-bin/wa?SUBED1=birdwg01
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Subject: Re: Subspecies and AOU Check-list
From: sgmlod(AT)AOL.COM
Date: 9 Jun 2005 10:32am
----INCLUDING text/plain MIME SECTION----
Well, there are car races, speed races, racey topics... :o)
I've always been under the impression that race and subspecies are synonyms, and
I've certainly seen them used that way in NAB at least.
SteveM
-----Original Message-----
From: Jean Iron <jeaniron(AT)SYMPATICO.CA>
To: BIRDWG01(AT)LISTSERV.ARIZONA.EDU
Sent: Thu, 9 Jun 2005 12:10:47 -0400
Subject: Re: [BIRDWG01] Subspecies and AOU Check-list
Hi Joe,
I disagree. In ornithology: subspecies, race, and geographic race all have the
same meaning. The term subspecies tends to be the formal name for the concept.
Ron Pittaway
Minden and Toronto
jeaniron(AT)sympatico.ca
At 08:56 AM 6/9/2005 -0700, Joseph Morlan wrote:
>On Thu, 9 Jun 2005 09:28:00 -0400, Jean Iron <jeaniron(AT)SYMPATICO.CA> wrote:
>
> >*Subspecies and race are synonymous.
>
>Not exactly. There are many different types of races. Subspecies are
>merely one of those types, the "geographic race."
>
> >Most North American ornithologists and
> >birders prefer using the term subspecies whereas the term race is preferred
> >in Britain and Ireland.
>--
>Joseph Morlan, Pacifica, CA 94044 jmorlan (at) ccsf.org
>Fall Birding Classes start Sep 13 http://fog.ccsf.edu/~jmorlan/
>California Bird Records Committee http://www.wfo-cbrc.org/cbrc/
>
>
>Join or Leave BIRDWG01: http://listserv.arizona.edu/cgi-bin/wa?SUBED1=birdwg01
>
>Archives: http://listserv.arizona.edu/archives/birdwg01.html
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Subject: Re: Subspecies and AOU Check-list
From: Dick Newell <dick.newell(AT)ZEN.CO.UK>
Date: 9 Jun 2005 10:41am
> This message is in MIME format. Since your mail reader does not understand
this format, some or all of this message may not be legible.
----INCLUDING text/plain MIME SECTION----
If the races of man are really subspecies, then which one is the nominate
sapiens?
I guess this has now gone too far off topic =AD not to mention politically
incorrect.
Dick Newell
Cambridge, UK
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Subject: Re: Subspecies
From: sgmlod(AT)AOL.COM
Date: 9 Jun 2005 10:49am
----INCLUDING text/plain MIME SECTION----
Greetings
First of all, let me be clear. I do not mean to imply that subspecies are
destined to become separate species. If they are truly subspecies (ie, not
reproductively isolated) such should NOT occur. However, I think most true
subspecies were at one point headed in different directions and that was
interrupted by geological/climatic events that put the two populations back in
contact before fully speciated. I am applying this to subspecies that are in
close contact yet meeting Amadon's rule.
The ends of a cline are not how I envision Amadon's principle being applied,
rather I see it as being used in populations that are in contact with each
other. Used in such a fashion, I think it is a most useful definition.
Obviously, the term "subspecies" is a human invention, and no definition is
going to be fully satisfactory. Is anyone aware of a better definition?
Finally, the world is not static. Two species do not occupy the same niche
forever. But they can, temporarily, as they "struggle" against each other. One
could easily argue that such is happening with Townsends/Hermit Warblers in WA
and BW/GW Warblers in e. NA. I guess it partly depends on how finely you parse
the term niche. Certainly Beldings/Large-billed Sparrows occupy a niche that's
far different from the remainder of the Savannah Sparrow complex when compared
with the niches filled by Hermit/Townsend's.
Best Wishes
Steven Mlodinow
-----Original Message-----
From: Joseph Morlan <jmorlan(AT)ccsf.org>
To: sgmlod(AT)AOL.COM
Cc: BIRDWG01(AT)LISTSERV.ARIZONA.EDU
Sent: Thu, 09 Jun 2005 09:38:41 -0700
Subject: Re: [BIRDWG01] Subspecies
On Thu, 9 Jun 2005 11:08:15 -0400, sgmlod(AT)AOL.COM wrote:
>Greetings All
>
>Indeed, many subspecies (as defined by Amadon, not the vast array found in the
1957 AOU check-list) probably have travelled part way towards being separate
species.
A colleague wrote privately, expressing my thoughts better than I did. He
wrote, "Subspecies are not necessarily destined to become a new species.
This is a big misunderstanding that people have, as if there is some drive
for species to be created, and subspecies are working their way up the
ladder to reach this goal. This may or may not happen, but clearly in birds
geographic isolation is a pre-requisite (other than in this ring species
they have "confirmed" on one of the Old World Warblers)."
>Many of these populations are thought to have been separated by previous
climatic events, such as iceages, and then come into contact again at a later
date. They've differentiated enough to be somewhat different but not enough to
be fully reproductively isolated. The Fox Sparrows are a great example. They
occupy totally different niches in WA. Similarly, LB Sparrow and Ipswich Sparrow
(and Belding's) occupy very different niches from the main swarm of Sav Sparrow
races (which to most folks eyes would not meet Amadon's rules). Yes there are
exceptions. This is a sloppy business where no "rule" is going to work, but I
still think Amadon's rule forms a great starting base allowing for scientific
work to be done rather than willy-nilly "this population seems different from
that to me." Part of the reason we don't see
> it applied much now is that there seems to virtually no work on subspecies
being done, unless its trying to discern if they are really separate species.
>
>For subspecies representing step-clines, it is hard to imagine how they would
arise WITHOUT being geographically isolated at some point. For those
representing steady clines, few would meet Amadon's rule.
Many populations at the extreme ends of a long cline easily meet Amadon's
rule without ever having been geographically isolated. Furthermore, I
think it's too easy to create "valid" subspecies using Amadon's 75% rule,
simply by multiplying the number of characters used to assess differences.
>And there is no "rule" stating that species occupy separate niches.
Mayr included it as part of his 1982 amended definition of biological
species: "A species is a reproductive community of populations
(reproductively isolated from others) that occupies a specific niche in
nature." (Mayr E. 1982. The Growth of Biological Thought. Harvard
University Press, Cambridge, Mass.)
It is a consequence of competitive exclusion which occurs when similar
species overlap. Thus each species occupies a unique niche in nature.
>The rule, currently, is that there is not significant gene flow. These are
different things, for two populations can be reproductively isolated and fill
the same niche.
Such populations, if they exist, would be extremely interesting to
evolutionary biologists because they would violate Gause's Law of
Competitive Exclusion. I am unaware of any examples of this which have
been exhaustively examined.
>There is a tendency, over time, for this not to happen, because two species
trying to occupy the same niche will eventually lead to a "winner" and a "loser"
which is excluded.
Agreed. Natural selection, as an evolutionary force, occurs only among
individuals which compete directly for limited resources. That normally
means individual members of the same species.
--
Joseph Morlan, Pacifica, CA 94044 jmorlan (at) ccsf.org
Fall Birding Classes start Sep 13 http://fog.ccsf.edu/~jmorlan/
California Bird Records Committee http://www.wfo-cbrc.org/cbrc/
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: Help with small Calidrid
From: Don Roberson <creagrus(AT)montereybay.com>
Date: 9 Jun 2005 5:59pm
We would appreciate comments on an alternate-plumaged small Calidrid,
either a Western or Semipalmated Sanpiper (it had a bit of webbing
between the toes), that was in Monterey County, central coastal
California, for a couple days in early June. The bird did not have as
stout or blob-tipped a bill as might be hoped, and opinions are split.
There are only a couple spring records of Semi in this county, and none
as late as 3-4 June.
Digiscoped photos from the two days are at
http://montereybay.com/creagrus/MTYlistSESA.html
Thank you for your help,
Don Roberson
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Subject: Re: Help with small Calidrid
From: Julian Hough <jrhough1(AT)SNET.NET>
Date: 9 Jun 2005 6:38pm
Don,
Looking at the pix, I think the bird is a Western Sandpiper. Without looking
at plumage detail too closely, the overall jizz and shape of the bill seem
to point more in favour as Western. To me, the bill shape, as opposed to
length (which overalaps in both species) seems more Western than Semi-p. It
tapers to a fairly fine-tip, compared to a typical (most/) Semi-ps.
The other feature that points me in favour of Western is the colour and
distribution of the dark markings on the underparts. They look blackish, not
brownish, and extend further down into the carpal area and towards the
center of the belly than I see in Semi-p.
Adult Semi-ps I see here in CT right now through July are very variable,
some with well-marked breast/pectoral bands whereby the breast streaks
extend down into the carpal region (but not lower down toward the belly) but
they are generally restricted to this area, with occasionally finer,
hair-like streaks extending sparesely along the rear flanks in some
individuals.
Your bird has breast markings on the lower breast that are quite sparse and
not close together and is not a pattern I see as fitting in with Semi-ps I
see here during late spring and summer. Also the shape of some of the
markings in your bird look chevron/arrow-shaped, which is good for Western
rather than Semi-p. pattern.
The pattern of the upperpart feathers is tough to discern and so I can't
really add anything. The head pattern seems to fit Western, rather pale
lacking the dark-capped and dark earcovert on Semi-ps which give them a more
uniformly, dark-headed look.
There, I stuck my neck out...hope the blade isn't too sharp!
Best,
Julian Hough,
CT, USA
jrhough1(AT)snet.net
www.naturescapeimages.net
----- Original Message -----
From: "Don Roberson" <creagrus(AT)MONTEREYBAY.COM>
To: <BIRDWG01(AT)LISTSERV.ARIZONA.EDU>
Sent: Thursday, June 09, 2005 9:02 PM
Subject: [BIRDWG01] Help with small Calidrid
> We would appreciate comments on an alternate-plumaged small Calidrid,
> either a Western or Semipalmated Sanpiper (it had a bit of webbing
> between the toes), that was in Monterey County, central coastal
> California, for a couple days in early June. The bird did not have as
> stout or blob-tipped a bill as might be hoped, and opinions are split.
> There are only a couple spring records of Semi in this county, and none
> as late as 3-4 June.
> Digiscoped photos from the two days are at
> http://montereybay.com/creagrus/MTYlistSESA.html
>
> Thank you for your help,
> Don Roberson
>
>
> Join or Leave BIRDWG01:
> http://listserv.arizona.edu/cgi-bin/wa?SUBED1=birdwg01
>
> Archives: http://listserv.arizona.edu/archives/birdwg01.html
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Subject: Re: Subspecies
From: Sam Stuart <surfbird(AT)gmail.com>
Date: 9 Jun 2005 8:41pm
----INCLUDING text/plain MIME SECTION----
To All,
I think there are some things to keep in mind when thinking about=20
subspecies and their validity. Subspecies do exist, but not all variation w=
e=20
see can be ordered into this division. A subspecies has been defined by=20
Mayer as "an aggregate of phenotypically similar populations of a species=
=20
inhabiting a geographic subdivision of the range of the species and=20
differing taxonomically from the other populations of the species." The 75%=
=20
rule is an accepted means of determining taxonomic difference.
Patten and Unit define this rule in the following terms: "to be a valid=20
subspecies 75% of a population effectively must lie outside 99% of the rang=
e=20
of other populations for a given defining character or set of characters." =
It=20
would make sense that the number of characters used to make a comparison=20
should include all the characters for which individuals in a population=20
vary. Therefore subspecies for species A might be defined by three=20
characters whereas species B's subspecies might be differentiated by five=
=20
characters. The more characters used the better as it would move the=20
subspecies concept away from mean differences and towards diagnosable=20
differences.
This concept does can't categorize clines very well as clines by their var=
y=20
nature aren't readily subdivide on a geographic level. Also not all=20
individuals will be identifiable to subspecies, especially if they lie=20
somewhere towards an extreme in a character that varies within the=20
population. Some of the older defined subspecies we are familiar with don't=
=20
fall into the current definition. They may have to be rework or considered=
=20
variable at a non-subspecific or taxonomic level. Light-morph *calurus *and=
=20
*borealis* Redtails are one possible example because of their lack of=20
diagnostically different characters. Subspecies are, however, important=20
especially in considering management concerns, federal protection and=20
identifying vagrants in specific areas such as finding odd Dowitchers in=20
your local patch! Lastly, subspecies may have distinctive ecologies but tha=
t=20
is not grounds for subspeficic classification. The Sage Sparrows of San=20
Clemente Island, CA don't nest in Sage, despite this Patten and Unit lump=
=20
them with another form based on the difficulty of separating them by=20
plumage.
Have a good day,
Sam Stuart
Join or Leave BIRDWG01:
http://listserv.arizona.edu/cgi-bin/wa?SUBED1=3Dbirdwg01
Archives: http://listserv.arizona.edu/archives/birdwg01.html
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Subject: Re: Help with small Calidrid
From: "Lethaby, Nick" <nlethaby(AT)TI.COM>
Date: 9 Jun 2005 9:44pm
Don:
I feel this is Western. I don't really see much case for a Semi, given
that it shows a fair amount of chevrons.
Nick Lethaby
DSP/BIOS Product Manager
Software Development Systems
Texas Instruments
805 562 5106
nlethaby(AT)ti.com
-----Original Message-----
From: NBHC ID-FRONTIERS Frontiers of Field Identification
[mailto:BIRDWG01(AT)LISTSERV.ARIZONA.EDU] On Behalf Of Don Roberson
Sent: Thursday, June 09, 2005 6:02 PM
To: BIRDWG01(AT)LISTSERV.ARIZONA.EDU
Subject: [BIRDWG01] Help with small Calidrid
We would appreciate comments on an alternate-plumaged small Calidrid,
either a Western or Semipalmated Sanpiper (it had a bit of webbing
between the toes), that was in Monterey County, central coastal
California, for a couple days in early June. The bird did not have as
stout or blob-tipped a bill as might be hoped, and opinions are split.
There are only a couple spring records of Semi in this county, and none
as late as 3-4 June.
Digiscoped photos from the two days are at
http://montereybay.com/creagrus/MTYlistSESA.html
Thank you for your help,
Don Roberson
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
[ << | >> | ^^ ]
Subject: Re: Help with small Calidrid
From: "Thomas J. Dunkerton" <Woundedmallard67(AT)AOL.COM>
Date: 10 Jun 2005 5:20am
----INCLUDING text/plain MIME SECTION----
Don,
I've taken my share of heat over here on the east coast for having the
audacity to see Semi 'pipers in March! lol
Your bird however appears to be a Western to me. The overlap in bill
length between the two calidrids is only a mere 2mm. Semi's 15-23mm and
Western
21-30mm. The bird in question appears to be on the short end of that
spectrum, in addition it has a much finer tip than a Semi would have.
The chevron markings on the breast are stronger as opposed to the
typically finer streaking of a Semi.
See you out there!
Thomas J. Dunkerton
Titusville, Florida
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Subject: Re: Subspecies
From: Alvaro Jaramillo <chucao(AT)COASTSIDE.NET>
Date: 10 Jun 2005 10:27am
This is a multi-part message in MIME format.
----INCLUDING text/plain MIME SECTION----
Stuart et al.=20
=20
I just want to comment on the use of the Red-tailed Hawk as an =
example,
as it got me thinking. I recall having discussions with folks in =
university
about naming a subspecies based on a single plumage or stage and if this =
was
OK. Let=92s suppose that adults of two hypothetical bird populations are
exactly the same, but the juveniles of one are bright orange-yellow, =
while
the other population has olive-yellow juveniles. Is it OK to name a
subspecies in this case? I think that the general concensus was that it =
was
ok, and I think we found some examples of subspecies based on female
plumages, probably antbirds! But the real kicker was that many =
subspecies
are named based on differences only in male plumages, or only in adult
plumages. So really, naming of a subspecies based on a subset of the
plumages it shows is not unusual, it is only unusual if that plumage is =
not
the adult or the male. However, the key here is that you need to look at =
the
population level. So you have to compare series of birds from different
populations, not individuals. This is where the hawk example comes in. =
To
me, the fact that light morph calurus and borealis may lack diagnosable
plumage characters (not sure I agree with that completely, but that is
another point) is only part of the full story. In terms of subspecies,
thinking at the population level, the fact that calurus has a dark morph =
and
borealis does not is a valid character that can be used to separate the =
two
subspecies. This is an important character in my opinion, and come to =
think
of it, the situation causes a great problem for the 75% rule. Before
everyone asks, then why not separate every population that has a =
different
morph, I should clarify. These Red-tailed Hawk subspecies were named =
based
on other characters, and almost surely only concentrating on the pale
morphs, but the fact that the dark morph is restricted to only one of =
these
subspecies is of interest. So no, naming different subspecies of jaegers
based on local morph ratios is not a good idea, but if a good =
subspecies,
based on other characters, has or lacks a morph unlike the other =
subspecies,
that seems important to me. =20
=20
On a related note, a recent molecular phylogeny of Buteo found that the
Red-tailed Hawk has a moderately deep genetic division between the =
eastern
and western populations. Eastern birds fall into a clade (group of close
relatives) that includes the Caribbean subspecies, while the Western =
group
includes the Patagonian species Buteo ventralis, the Rufous-tailed Hawk.
The eastern group does not have a dark morph, the western one, including
Rufous-tailed Hawk does. The problem is that a key taxon, Harlan=92s =
Hawk, was
missing from the analysis, so the full picture is not quite there yet. =
As
the genetic data stands the resolution to this would be to lump all of =
these
birds, including the really distant, geographically speaking, =
Rufous-tailed
Hawk as one species or to start conducting work to see if Eastern and
Western groups of Red-tailed Hawk are better classed as two species. =
Neither
of these options is all that good, given our present knowledge. =
Therefore,
more work is needed, both on interbreeding at the contact zone, =
morphology,
and using larger sample sizes and other gene groups.=20
=20
Regards
=20
Al
=20
Alvaro Jaramillo
chucao(AT)coastside.net
Half Moon Bay, CA
=20
Field Guides - Birding Tours Worldwide
http://www.fieldguides.com/home.htm
=20
_____ =20
From: NBHC ID-FRONTIERS Frontiers of Field Identification
[mailto:BIRDWG01(AT)LISTSERV.ARIZONA.EDU] On Behalf Of Sam Stuart
Sent: Thursday, June 09, 2005 8:31 PM
To: BIRDWG01(AT)LISTSERV.ARIZONA.EDU
Subject: Re: [BIRDWG01] Subspecies
=20
To All,
=20
I think there are some things to keep in mind when thinking about =
subspecies
and their validity. Subspecies do exist, but not all variation we see =
can
be ordered into this division. A subspecies has been defined by Mayer =
as
"an aggregate of phenotypically similar populations of a species =
inhabiting
a geographic subdivision of the range of the species and differing
taxonomically from the other populations of the species." The 75% rule =
is
an accepted means of determining taxonomic difference.
=20
Patten and Unit define this rule in the following terms: "to be a valid
subspecies 75% of a population effectively must lie outside 99% of the =
range
of other populations for a given defining character or set of =
characters."
It would make sense that the number of characters used to make a =
comparison
should include all the characters for which individuals in a population
vary. Therefore subspecies for species A might be defined by three
characters whereas species B's subspecies might be differentiated by =
five
characters. The more characters used the better as it would move the
subspecies concept away from mean differences and towards diagnosable
differences.=20
=20
This concept does can't categorize clines very well as clines by their =
vary
nature aren't readily subdivide on a geographic level. Also not all
individuals will be identifiable to subspecies, especially if they lie
somewhere towards an extreme in a character that varies within the
population. Some of the older defined subspecies we are familiar with
don't fall into the current definition. They may have to be rework or
considered variable at a non-subspecific or taxonomic level. =
Light-morph
calurus and borealis Redtails are one possible example because of their =
lack
of diagnostically different characters. Subspecies are, however, =
important
especially in considering management concerns, federal protection and
identifying vagrants in specific areas such as finding odd Dowitchers in
your local patch! Lastly, subspecies may have distinctive ecologies but
that is not grounds for subspeficic classification. The Sage Sparrows =
of
San Clemente Island, CA don't nest in Sage, despite this Patten and Unit
lump them with another form based on the difficulty of separating them =
by
plumage.=20
=20
Have a good day,
Sam Stuart
Join or Leave BIRDWG01:
http://listserv.arizona.edu/cgi-bin/wa?SUBED1=3Dbirdwg01=20
Archives: http://listserv.arizona.edu/archives/birdwg01.html=20
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Subject: Re: Subspecies
From: GreatGrayOwl(AT)AOL.COM
Date: 10 Jun 2005 7:23pm
----INCLUDING text/plain MIME SECTION----
Hi all:
I agree with Alvaro's thesis, but wanted to drop my two-cents' worth about
the diagnosability of calurus and borealis Red-tails. Having lived and worked
in both the east and west and having conducted hawk counts in both the east
and west, I don't really have any problem with separating eastern and western
Red-tails (even light morphs). EXCEPT, in eastern CO, there is all manner
of apparent gene flow. But in areas well removed from the meeting of the two
in the western prairies, I find the two relatively easy to differentiate --
even with that darn western-like abieticola from northeastern Canada messing
up the works in the east.
Sincerely,
Tony Leukering
Brighton, CO
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Subject: Another Glossy Ibis?
From: Cliff and Lisa Weisse <october(AT)IDA.NET>
Date: 11 Jun 2005 7:40pm
A friend photographed an Ibis today at Camas NWR in Idaho
that was identified as a Glossy Ibis. Since it would be a
first state record (and he's not subscribed) he asked me to
post this query soliciting opinions regarding the ID of this
bird from those of you that are experienced with Glossy
Ibis. Photographs are at
http://www.darrenclarkphoto.net/birds/ibis/index.htm. You
can post to the list or to me directly and I'll forward your
comments. Thanks in advance.
Cliff
Cliff and Lisa Weisse
Island Park, ID
october(AT)ida.net
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