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ID-FRONTIERS for May 26-31, 2002
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Messages are displayed in the order they were received.
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| Subject | From | Date | Time |
| More CAVI audio via my web page | Martin Reid | Sun, 26 May 2002 | 4:04am |
| Re: More CAVI audio via my web page | Barb Beck | Sun, 26 May 2002 | 6:10am |
| Re: More CAVI audio via my web page | Sebastian Patti | Sun, 26 May 2002 | 8:01am |
| Re: Santa Barbara Solitary Vireo, etc. | Lethaby, Nick | Sun, 26 May 2002 | 6:59pm |
| Common Ringed Plover in Québec now | Michel Bertrand | Mon, 27 May 2002 | 8:24am |
| Eur Collared Dove | Steven Mlodinow | Mon, 27 May 2002 | 2:56pm |
| Re: RFH: audio of poss. Cassin's Vireo - Fort
Worth | David Sibley | Tue, 28 May 2002 | 7:58am |
| Re: Eur Collared Dove | Peter Wilkinson | Tue, 28 May 2002 | 8:16am |
| Re: RFH: audio of poss. Cassin's Vireo - Fort
Worth | Barb Beck | Tue, 28 May 2002 | 8:34am |
| Solitary Vireos | Matt Heindel | Tue, 28 May 2002 | 9:58am |
| "Alaskan" Blackpolls | Evan Obercian | Tue, 28 May 2002 | 10:23am |
| Re: "Alaskan" Blackpolls | Evan Obercian | Tue, 28 May 2002 | 6:15pm |
| Re: "Alaskan" Blackpolls | Eric Preston | Tue, 28 May 2002 | 8:21pm |
| Re 2 : Common Ringed Plover in Québec now | Michel Bertrand | Wed, 29 May 2002 | 10:39am |
| Re: "Alaskan" Blackpolls | Michael O'Brien | Wed, 29 May 2002 | 12:53pm |
| "Alaskan" Blackpolls | LVM | Wed, 29 May 2002 | 1:28pm |
| Oups ! | Michel Bertrand | Wed, 29 May 2002 | 9:33pm |
| Explanation requested: Solitary
Vireos | JIm Barton | Thu, 30 May 2002 | 3:04pm |
| Solitary Vireo | Matt Heindel | Fri, 31 May 2002 | 7:31pm |
|
To use email addresses replace '(AT)' with '@'.
This is done to confuse the spam 'bots.
|
[ << | >> | ^^ ]
Subject: More CAVI audio via my web page
From: Martin Reid <upupa(AT)AIRMAIL.NET>
Date: 26 May 2002 4:04am
Dear all,
Doug Von Gausig has kindly made available a clip, plus I've added a link to
a 2nd clip by Doug; these two are similar in content but at very different
delivery speeds; any comments on this?:
http://www.martinreid.com/vireoa.html
(with certain browser security settings, you'll have to right-click over
the clips and "save target as" )
Martin
Martin Reid
Fort Worth, Texas
upupa(AT)airmail.net
http://www.martinreid.com
[ << | >> | ^^ ]
Subject: Re: More CAVI audio via my web page
From: Barb Beck <barb(AT)BIRDNUT.OBTUSE.COM>
Date: 26 May 2002 6:10am
The speed at which he vireos sing depends on the time of day and how hot it
is. In the cool of early morning they go the faster, as it heats up and the
day wears on they slow down greatly.
Barb Beck
-----Original Message-----
From: NBHC ID-FRONTIERS Frontiers of Field Identification
[mailto:BIRDWG01(AT)listserv.arizona.edu]On Behalf Of Martin Reid
Sent: May 26, 2002 5:07 AM
To: BIRDWG01(AT)listserv.arizona.edu
Subject: [BIRDWG01] More CAVI audio via my web page
Dear all,
Doug Von Gausig has kindly made available a clip, plus I've added a link to
a 2nd clip by Doug; these two are similar in content but at very different
delivery speeds; any comments on this?:
http://www.martinreid.com/vireoa.html
(with certain browser security settings, you'll have to right-click over
the clips and "save target as" )
Martin
Martin Reid
Fort Worth, Texas
upupa(AT)airmail.net
http://www.martinreid.com
[ << | >> | ^^ ]
Subject: Re: More CAVI audio via my web page
From: Sebastian Patti <sebastianpatti(AT)HOTMAIL.COM>
Date: 26 May 2002 8:01am
Hello all . . .this stuff IS interesting . . .I live in Chicago (where BHVI
is pretty common) and bird quite a bit in Kansas where (in the western part
of the state) CAVI, BHVI and PLVI all occur . . .only clip 1b seems to me to
be "burry" or husky enough for CAVI, but it really does sound good for
Cassin's . . .on the other hand, the other clips sound to me like BHVI . .
.sooo . . .since we're dealing with taxa that can learn the "wrong" song, it
may just be that the physical description of the indivdual bird will have to
be the determinative factor . . .just a thought . . .Happy Memorial Day!!
>From: Martin Reid <upupa(AT)AIRMAIL.NET>
>Reply-To: Martin Reid <upupa(AT)AIRMAIL.NET>
>To: BIRDWG01(AT)listserv.arizona.edu
>Subject: [BIRDWG01] More CAVI audio via my web page
>Date: Sun, 26 May 2002 06:06:47 -0500
>
>Dear all,
>Doug Von Gausig has kindly made available a clip, plus I've added a link to
>a 2nd clip by Doug; these two are similar in content but at very different
>delivery speeds; any comments on this?:
>http://www.martinreid.com/vireoa.html
>(with certain browser security settings, you'll have to right-click over
>the clips and "save target as" )
>Martin
>
>Martin Reid
>Fort Worth, Texas
>upupa(AT)airmail.net
>http://www.martinreid.com
sebastianpatti(AT)hotmail.com
Sebastian T. Patti
(Lincoln Park)
Chicago, ILLINOIS 60614-3354
PHONE: 312/603-4416 (o) 773/248-0570 (h)
FAX: 312/603-2041 (o) 773/248-0264 (h)
Hello . . .this stuff IS interesting . . .I live in Chicago (where BHVI is
pretty common) and bird quite a bit in Kansas where (in the western part of
the state) BOTH CAVI and BHVI occur . . .only clip 1b seems to me to be
"burry" or husky enough for CAVI, but it really does sound good for Cassin's
. . .on the other hand, the other clips sound to me like BHVI . . .sooo . .
.since we're dealing with taxa that can learn the "wrong" song, it may just
be that the physical description of the indivdual bird will have to be the
determinative factor . . .just a thought . . .
>From: Martin Reid <upupa(AT)AIRMAIL.NET>
>Reply-To: Martin Reid <upupa(AT)AIRMAIL.NET>
>To: BIRDWG01(AT)listserv.arizona.edu
>Subject: [BIRDWG01] More CAVI audio via my web page
>Date: Sun, 26 May 2002 06:06:47 -0500
>
>Dear all,
>Doug Von Gausig has kindly made available a clip, plus I've added a link to
>a 2nd clip by Doug; these two are similar in content but at very different
>delivery speeds; any comments on this?:
>http://www.martinreid.com/vireoa.html
>(with certain browser security settings, you'll have to right-click over
>the clips and "save target as" )
>Martin
>
>Martin Reid
>Fort Worth, Texas
>upupa(AT)airmail.net
>http://www.martinreid.com
sebastianpatti(AT)hotmail.com
Sebastian T. Patti
(Lincoln Park)
Chicago, ILLINOIS 60614-3354
PHONE: 312/603-4416 (o) 773/248-0570 (h)
FAX: 312/603-2041 (o) 773/248-0264 (h)
Hello . . .this stuff IS interesting . . .I live in Chicago (where BHVI is
pretty common) and bird quite a bit in Kansas where (in the western part of
the state) BOTH CAVI and BHVI occur . . .only clip 1b seems to me to be
"burry" or husky enough for CAVI, but it really does sound good for Cassin's
. . .on the other hand, the other clips sound to me like BHVI . . .sooo . .
.since we're dealing with taxa that can learn the "wrong" song, it may just
be that the physical description of the indivdual bird will have to be the
determinative factor . . .just a thought . . .
>From: Martin Reid <upupa(AT)AIRMAIL.NET>
>Reply-To: Martin Reid <upupa(AT)AIRMAIL.NET>
>To: BIRDWG01(AT)listserv.arizona.edu
>Subject: [BIRDWG01] More CAVI audio via my web page
>Date: Sun, 26 May 2002 06:06:47 -0500
>
>Dear all,
>Doug Von Gausig has kindly made available a clip, plus I've added a link to
>a 2nd clip by Doug; these two are similar in content but at very different
>delivery speeds; any comments on this?:
>http://www.martinreid.com/vireoa.html
>(with certain browser security settings, you'll have to right-click over
>the clips and "save target as" )
>Martin
>
>Martin Reid
>Fort Worth, Texas
>upupa(AT)airmail.net
>http://www.martinreid.com
sebastianpatti(AT)hotmail.com
Sebastian T. Patti
(Lincoln Park)
Chicago, ILLINOIS 60614-3354
PHONE: 312/603-4416 (o) 773/248-0570 (h)
FAX: 312/603-2041 (o) 773/248-0264 (h)
Hello . . .this stuff IS interesting . . .I live in Chicago (where BHVI is
pretty common) and bird quite a bit in Kansas where (in the western part of
the state) BOTH CAVI and BHVI occur . . .only clip 1b seems to me to be
"burry" or husky enough for CAVI, but it really does sound good for Cassin's
. . .on the other hand, the other clips sound to me like BHVI . . .sooo . .
.since we're dealing with taxa that can learn the "wrong" song, it may just
be that the physical description of the indivdual bird will have to be the
determinative factor . . .just a thought . . .
>From: Martin Reid <upupa(AT)AIRMAIL.NET>
>Reply-To: Martin Reid <upupa(AT)AIRMAIL.NET>
>To: BIRDWG01(AT)listserv.arizona.edu
>Subject: [BIRDWG01] More CAVI audio via my web page
>Date: Sun, 26 May 2002 06:06:47 -0500
>
>Dear all,
>Doug Von Gausig has kindly made available a clip, plus I've added a link to
>a 2nd clip by Doug; these two are similar in content but at very different
>delivery speeds; any comments on this?:
>http://www.martinreid.com/vireoa.html
>(with certain browser security settings, you'll have to right-click over
>the clips and "save target as" )
>Martin
>
>Martin Reid
>Fort Worth, Texas
>upupa(AT)airmail.net
>http://www.martinreid.com
sebastianpatti(AT)hotmail.com
Sebastian T. Patti
(Lincoln Park)
Chicago, ILLINOIS 60614-3354
PHONE: 312/603-4416 (o) 773/248-0570 (h)
FAX: 312/603-2041 (o) 773/248-0264 (h)
_________________________________________________________________
Send and receive Hotmail on your mobile device: http://mobile.msn.com
[ << | >> | ^^ ]
Subject: Re: Santa Barbara Solitary Vireo, etc.
From: "Lethaby, Nick" <nlethaby(AT)TI.COM>
Date: 26 May 2002 6:59pm
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----
It was decided that it was presumably a CAVI because of the song. Looking at
the Colorado pictures, I feel this bird was fine for the bright Cassin's
they had. However, when it was originally found (in a net by banders) it was
called a BHVI.
-----Original Message-----
From: Martin Reid [mailto:upupa(AT)AIRMAIL.NET]
Sent: Saturday, May 25, 2002 5:40 AM
To: BIRDWG01(AT)listserv.arizona.edu
Subject: Re: [BIRDWG01] Santa Barbara Solitary Vireo, etc.
Dear all,
Following Nick Lethaby's email, I find this fascinating. Given the
situation, I'd think that any SOVI in California that sang like a CAVI
would have to be quite a long way beyond the overlap zone for it to be IDed
a cross-singing BHVi..... was it?
With this record and the Farallon one I referred to in my previous post, I
am not questioning the ID - I am trying to learn how to ID these buggers,
and we now seem to have two captured birds that were unusual (one on voice,
one on plumage IMO) yet were ID-able as BHVi. This is comforting to know,
but it would sure help the rest of us to know how these IDs were made. Is
anyone who was involved with the ID of these two birds out there? can you
help us out with a bit more info? - thanks.
Also, since Tony was brave enough to offer his experience and web
statements to us on ID-F concerning the bird at:
http://www.cfo-link.org/leadpage.html (Photo quiz; Nov/Dec '01 Solutions),
I'd like to ask: are the various ID comments made at this web page
accurate? Obviously the creators of the page have good experience to base
it on - but we all benefit from even more experience, and I'm sure that if
someone out there is reading it and muttering "that's not right
because....", that the authors would be the first to want to know why (back
me up or shoot me down, Tony!) It would be a shame to miss this
opportunity to pool our knowledge on this issue (isn't that what ID-F was
created for?). If you have solid experience to back-up or refute any of
the statements made at the Colorado web page, PLEASE tell us - thank you.
Martin
Martin Reid
Fort Worth, Texas
upupa(AT)airmail.net
http://www.martinreid.com
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[ << | >> | ^^ ]
Subject: Common Ringed Plover in Québec now
From: Michel Bertrand <bertrmi(AT)COLBA.NET>
Date: 27 May 2002 8:24am
Hi,
I have got a great lifer yesterday. This bird could interest those of you
living not too far from Québec. It is a Common Ringed Plover (Pluvier
grand-gravelot, Charadrius hiaticula).
The bird has been all day long in a field along Janelle road, at
Baie-du-Febvre (a bit more than 100 km east of Montréal on Saint-Laurent
river southshore) for the greatest pleasure of the birders alerted by a
message sent on Ornitho-Qc lately on Saturday. The bird has been discovered
by François Grenon who sent a very precise description that you can find at
http://birdingonthe.net/mailinglists/ORNQ.html#1022388020
I have had relatively close looks at the bird with my scope and has been
able to check all the field marks, including the white frontal spot which
reaches the eye in an elongated way (very good field mark it seems for
males, according to what I have been able to check from many photos of
Common Ringed Plovers, the spot being rounder and separated from the eye on
Semipalmated Plover), the eye without ring, the long and wide white eyebrow,
the longer bill, the very broad breast band (but varying with the bird
attitude) and, quickly, the lacking web between the internal toes and very
small web between the external toes. Pierre Bannon has had the chance to
check the call too. There were a lot of Semipalmated Plover there to compare
with, and many other shorebirds.
If you want to come, don't wait too much. It will be sunny for coming days
and the field will dry. If you come, stop also at the last artificial pond
on Janelle road. There were a Red-necked Phalarope (very pretty female, more
colored than the male in those birds) and 9 Wilson's Phalaropes in it
yesterday, with many species of ducks. Ruddy Ducks and Red-headed Ducks,
rare elsewhere in Québec, are nesting in the very large pond looking more
natural (but with regulated water level) after the artificial looking ones.
I also have seen a Bar-headed Goose which has been reported near Black Lake,
but it is surely an escapee. Nice bird, anyway.
Be happy...
MICHEL BERTRAND
Sainte-Julie, Qc
bertrmi(AT)colba.net
Félicitations au peuple du Timor oriental
de la part du peuple timoré occidental !
[ << | >> | ^^ ]
Subject: Eur Collared Dove
From: Steven Mlodinow <SGMlod(AT)AOL.COM>
Date: 27 May 2002 2:56pm
----INCLUDING text/plain MIME SECTION----
Greetings All
I know that there was recently a fair amount of discussion about ECD ID. I am
sorry to revisit this and will make my question brief.
A month or so ago, a collared-dove like bird was photographed in e. WA. I
think it is probably a ECD X Ringed Turtle-Dove.
Does white undertail coverts fully eliminate pure ECD?
Cheers
Steve Mlodinow
----DELETED text/html MIME SECTION----
[ << | >> | ^^ ]
Subject: Re: RFH: audio of poss. Cassin's Vireo - Fort
Worth
From: David Sibley <dsibley(AT)SHORE.NET>
Date: 28 May 2002 7:58am
This is a multi-part message in MIME format.
----INCLUDING text/plain MIME SECTION----
RE: [BIRDWG01] RFH: audio of poss. Cassin's Vireo - Fort WorthI've taken =
another look at the paper by James, 1981 (Can. J. Zool. 59:2001-2009). =
In it he states that "There are no abrupt changes between subspecies" =
songs except where populations are isolated as in Baja California. He =
also concludes that the amount of frequency modulation (burriness) in =
the song phrases decreases northward along the Pacific Coast and then =
eastward through the widespread solitarius (Blue-headed). "There is no =
indication of an abrupt change ... between eastern or western portions =
of the species distribution."
On the other hand, his sample sizes are small, and his recordings of =
so-called Blue-headed from Alberta singing frequency-modulated phrases =
are not backed up by any information on how he identified them as =
Blue-headed. Unfortunately he doesn't even say exactly where the =
recordings were made. The important conclusion from his paper, =
confirming earlier work which he cites, is that there is a lot of =
song-sharing, so that Solitary vireos from adjacent regions share many =
song phrases with each other, and that as one travels farther from that =
region fewer songs phrases are shared. The Blue-headed vireos in =
Pennsylvania have more in common with those in New York than they do =
with the ones in Saskatchewan. Since songs seem to be learned in these =
vireos, that suggests that any young vireo will grow up singing the =
songs it hears as a youngster, and that any overlap zone will produce =
many birds with "mixed" songs.
That zone could be narrow, and James did not test that question, =
although he did record a few frequency-modulated phrases in Pennsylvania =
and clear-toned phrases in the far west. Barb Beck's experience suggests =
that there is a fairly abrupt transition from pure-toned Blue-headed =
songs in the east to frequency-modulated Cassin's songs in the Rocky =
Mountains. So song may be a more useful clue than James implies, but =
Barb's observation of occasional "Cassin's sounding" birds in the boreal =
forest east of the Rockies and "intermediate" songs as well, raises =
questions. How much do we really know about the details of this =
transition? I don't think the question of hybridization has ever been =
addressed. Why couldn't the so-called "bright Cassin's" from Colorado =
and Santa Barbara be hybrids? I don't think we have any way of knowing.=20
Since songs are learned and not inherited there is no reason to suspect =
that a hybrid will sing intermediate songs. A pure Blue-headed could =
sing Cassin's-type song or vice versa, a hybrid could sing pure song of =
either type, or any of these birds could sing mixed songs.=20
I think a lot more caution is called for before putting labels on these =
birds, both by sight and by sound, when lots of evidence points to =
overlap and intermediate individuals.=20
David Sibley
Concord, MA
----- Original Message -----=20
From: Barb Beck=20
To: BIRDWG01(AT)listserv.arizona.edu=20
Sent: Friday, May 24, 2002 8:57 PM
Subject: Re: [BIRDWG01] RFH: audio of poss. Cassin's Vireo - Fort =
Worth
This is a case like our "Western Flycatchers" where I am not =
comfortable in many cases identifying to the species level. I note =
which species it sounds like and if it is clearly one or the other =
visually great but I see a lot that are not. I am currently grumbling =
at the people running our bird atlas that they are requiring atlassers =
to put down the specific species in these complexes. To me that only =
leads to identification by a range map.
Anyway if anybody wants to hear mps clips of a couple of recordings I =
have from here let me know. They are about 250K each
Barb Beck
Edmonton, Alberta, Canada
-----Original Message-----
From: NBHC ID-FRONTIERS Frontiers of Field Identification =
[mailto:BIRDWG01(AT)listserv.arizona.edu]On Behalf Of Lethaby, Nick
Sent: May 24, 2002 1:53 PM
To: BIRDWG01(AT)listserv.arizona.edu
Subject: Re: [BIRDWG01] RFH: audio of poss. Cassin's Vireo - Fort =
Worth
Based on last winter's experience in Santa Barbara with a Solitary =
Vireo that most people were happy was a Blue-headed (it was even banded =
as such)on plumage but that sang like a Cassin's, I would agree that it =
may only be possible to id extreme individuals.
One point I'm not 100% clear on is whether Cassin's in winter can be =
brighter than those seen in spring/summer/fall. Matt's paper indicated =
that Cassin's could be similar to Plumbeous when in worn plumage in the =
spring. I am wondering if Cassin's in winter are typically brighter and =
can be confused more with BHVI, especially if birders aren't really =
familiar with BHVI. Certainly in Santa Barbara, we apparently had 2 =
other birds that observers thought were similar to the "BHVI" bird. It =
seems unlikely all 3 were BLVI especially as one sung like a Cassin's. I =
haven't looked up the moult info in Pyle, but if Cassin's has a =
post-fall migration full moult, one would expect birds in =
early-mid-winter to be brighter.
-----Original Message-----=20
From: Martin Reid [mailto:upupa(AT)AIRMAIL.NET]=20
Sent: Thursday, May 23, 2002 5:50 PM=20
To: BIRDWG01(AT)listserv.arizona.edu=20
Subject: Re: [BIRDWG01] RFH: audio of poss. Cassin's Vireo - Fort =
Worth=20
Dear All,=20
I thank David Sibley and Barb Beck for their contributions; these are =
the=20
only replies I've received from birders with good experience of =
singing=20
CAVI, and I especially value Barb's local experience in the apparent=20
contact zone.=20
It seems that even if voice changes in the Solitary complex are =
clinal,=20
there might be benchmark points along that cline that could be used to =
place any particular individual. Barb Beck is using her personal =
experience=20
to categorize songs into CAVI, intermediate, and BHVI (presumably of =
the=20
western group, and thus with some regular burriness?); if we add to =
this=20
the "classic" non-burry eastern BHVI and typical PLVI, we end up with =
five=20
types.=20
Presuming the situation to indeed be clinal, there will be some =
individuals=20
that fall between these "points on a scale" - but at least such a =
scale=20
would allow the voice of an individual bird to be placed into the =
scale=20
fairly accurately.=20
So, can we define such a scale? - I find myself asking "where would =
the=20
audio clips of the Fort Worth bird place it in such a scale?"=20
Presumably, any individual bird sounding just like CAVi, could =
actually be=20
a BHVI from the breeding contact zone that has learned the wrong song =
- but=20
what about vice versa?; all three forms winter in Oaxaca, so a CAVI =
could=20
learn even the eastern BHVI song from there - or does this "wrong =
song"=20
event only happen to juvs in the natal area?=20
Thus we seem to have BHVIs that can be non-burry or somewhat burry, =
plus=20
any individual suspected vagrant might instead be a "cross-singer" of =
the=20
commoner form.... it seems to me that for the purposes of ID-ing =
potential=20
vagrants, the voice is at best a supporting feature - something that =
does=20
not rule out the common form, no matter how "wrong" it sounds; is this =
a=20
reasonable conclusion?.=20
As to plumage, I'd like to suggest an exercise:- dig out Matt =
Heindel's=20
article on the "Solitary" vireos ( BIRDING Dec '96), open it at pages=20
468/469, then fold the front portion back on itself so that you are =
looking=20
at the bird in fig 12 on page 469 and the bird on the front cover:- =
which=20
one has the cleanest demarcation of the throat/auricular? Given that =
this=20
is held as just about the strongest out of a bunch of fairly subtle =
and=20
overlapping features, I feel that only the most extreme examples (e.g. =
Figs=20
1, 2, 3, 4, 6 and probably 11) could be identified AS VAGRANTS with =
any=20
degree of confidence; all the others would surely be "most like xxxx, =
but=20
yyyy cannot be ruled out". Keep in mind that I am talking here not of =
any=20
individual birder's ability to be right on this, but about how a RBC =
could=20
assess a record submission.=20
The point here is that from a vagrant standpoint, LOTS of these vireos =
will=20
not be firmly identifiable - true?=20
Regards,=20
Martin=20
FYI some images to consider:=20
http://www.wfo-cbrc.org/cbrc/photos/bhvi1.html - I'd love to know how =
this=20
bird is FIRMLY identifiable as a vagrant BHVI, as it seems to fall =
into (or=20
very close to) the overlap zone, to my inexperienced eye. There are =
no=20
biometric differences to use (correct?), so are there any in-the-hand=20
micro-features that are absolutely definitive? I am merely trying to =
learn=20
from this example.=20
http://www.wfo-cbrc.org/cbrc/photos/bhvi2.html=20
http://rip.physics.unk.edu/NOU/Photographs/CassinVireo.html=20
http://www.islandnet.com/~rpbo/photos/photo14.html=20
Martin Reid=20
Fort Worth, Texas=20
upupa(AT)airmail.net=20
http://www.martinreid.com=20
----DELETED text/html MIME SECTION----
[ << | >> | ^^ ]
Subject: Re: Eur Collared Dove
From: Peter Wilkinson <pcwilkinson(AT)CLARA.CO.UK>
Date: 28 May 2002 8:16am
I'm rather glad that Steve has revisited this as I have been meaning to
write to the list myself and now must!
I was on the island of La Gomera in the Canaries for just over two weeks
in April. Eurasian Collared Dove is a fairly recent arrival there and by
all accounts has encountered feral Ringed Turtle Doves (Streptopelia
(roseogrisea) risoria) there. Almost all were exactly what one would
expect of Eurasian Collareds, but a minimum of three birds had white
undertail coverts. All of those three had the pattern of Collared on
the underside of the outer tail feather and the white was limited to the
undertail coverts and did not extend up into the rest of the underparts:
one was calling exactly like Collared and one, a male, mated with a grey
undertail covert bird. I have to say that I doubt these birds were pure
Eurasian Collared: I have banded somewhere between 500 and 1000 here and
have never seen white undertail coverts and have examined a number of
skins in the British Museum specifically to compare decaocto with wild
roseogrisea, where the undertail covert colour and the pattern of the
underside of the outer tail feather are consistent differences and
easier for observers of isolated birds than the more subtle size,
structure and shade of colour differences that also go with the two
species. If they aren't pure birds, of course, their descendants unto
the nth generation will also never be pure, but I guess the undertail
coverts will go grey fairly quickly and we will never know.
I encountered three other interesting individuals on La Gomera. One was
heard only: the call was trisyllabic and like decaocto except that the
middle syllable had a rolled "r" in it - coo crrooo cuk (presumably
decaocto x risoria), one was a golden-fawn colour with paler feather
edgings on the upperparts giving a scalloped effect but with grey
undertail coverts and was identical to the rather rare pale sports of
decaocto that I have twice caught in the UK, while the third was
extremely pale all over. Unfortunately it was seen only briefly and I
was unable to tell if it was a leucistic bird, a hybrid or possibly even
a surviving risoria (though I think the latter unlikely).
I would be interested to see the photographs of the WA bird, if they
become available.
Peter Wilkinson
Wheathampstead, Herts, England
pcwilkinson(AT)clara.co.uk
[ << | >> | ^^ ]
Subject: Re: RFH: audio of poss. Cassin's Vireo - Fort
Worth
From: Barb Beck <barb(AT)BIRDNUT.OBTUSE.COM>
Date: 28 May 2002 8:34am
This is a multi-part message in MIME format.
----INCLUDING text/plain MIME SECTION----
RE: [BIRDWG01] RFH: audio of poss. Cassin's Vireo - Fort WorthThanks David
The Cassin sounding birds I am encountering are in the Swan Hills - (about
under the B in the word Alberta in the map on the back of your book.) That
is a strange place. We get some mountain birds there. For example there
are a lot of Varied Thrush. I have heard BOTH wrens there. The birds seem
to be too darned stupid to realize that it is not still called the Rocky
Mountains. - although if you look at the map in your book you see that it
actually is part of a mountainous extension going out from the Rockies.
We had a good long look at one of the "Cassin" sounding birds but honestly
neither my husband nor I was willing to bet the farm on the id.
Barb
-----Original Message-----
From: NBHC ID-FRONTIERS Frontiers of Field Identification
[mailto:BIRDWG01(AT)listserv.arizona.edu]On Behalf Of David Sibley
Sent: May 28, 2002 8:57 AM
To: BIRDWG01(AT)listserv.arizona.edu
Subject: Re: [BIRDWG01] RFH: audio of poss. Cassin's Vireo - Fort Worth
I've taken another look at the paper by James, 1981 (Can. J. Zool.
59:2001-2009). In it he states that "There are no abrupt changes between
subspecies" songs except where populations are isolated as in Baja
California. He also concludes that the amount of frequency modulation
(burriness) in the song phrases decreases northward along the Pacific Coast
and then eastward through the widespread solitarius (Blue-headed). "There is
no indication of an abrupt change ... between eastern or western portions of
the species distribution."
On the other hand, his sample sizes are small, and his recordings of
so-called Blue-headed from Alberta singing frequency-modulated phrases are
not backed up by any information on how he identified them as Blue-headed.
Unfortunately he doesn't even say exactly where the recordings were made.
The important conclusion from his paper, confirming earlier work which he
cites, is that there is a lot of song-sharing, so that Solitary vireos from
adjacent regions share many song phrases with each other, and that as one
travels farther from that region fewer songs phrases are shared. The
Blue-headed vireos in Pennsylvania have more in common with those in New
York than they do with the ones in Saskatchewan. Since songs seem to be
learned in these vireos, that suggests that any young vireo will grow up
singing the songs it hears as a youngster, and that any overlap zone will
produce many birds with "mixed" songs.
That zone could be narrow, and James did not test that question, although he
did record a few frequency-modulated phrases in Pennsylvania and clear-toned
phrases in the far west. Barb Beck's experience suggests that there is a
fairly abrupt transition from pure-toned Blue-headed songs in the east to
frequency-modulated Cassin's songs in the Rocky Mountains. So song may be a
more useful clue than James implies, but Barb's observation of occasional
"Cassin's sounding" birds in the boreal forest east of the Rockies and
"intermediate" songs as well, raises questions. How much do we really know
about the details of this transition? I don't think the question of
hybridization has ever been addressed. Why couldn't the so-called "bright
Cassin's" from Colorado and Santa Barbara be hybrids? I don't think we have
any way of knowing.
Since songs are learned and not inherited there is no reason to suspect that
a hybrid will sing intermediate songs. A pure Blue-headed could sing
Cassin's-type song or vice versa, a hybrid could sing pure song of either
type, or any of these birds could sing mixed songs.
I think a lot more caution is called for before putting labels on these
birds, both by sight and by sound, when lots of evidence points to overlap
and intermediate individuals.
David Sibley
Concord, MA
----- Original Message -----
From: Barb Beck
To: BIRDWG01(AT)listserv.arizona.edu
Sent: Friday, May 24, 2002 8:57 PM
Subject: Re: [BIRDWG01] RFH: audio of poss. Cassin's Vireo - Fort Worth
This is a case like our "Western Flycatchers" where I am not comfortable
in many cases identifying to the species level. I note which species it
sounds like and if it is clearly one or the other visually great but I see a
lot that are not. I am currently grumbling at the people running our bird
atlas that they are requiring atlassers to put down the specific species in
these complexes. To me that only leads to identification by a range map.
Anyway if anybody wants to hear mps clips of a couple of recordings I have
from here let me know. They are about 250K each
Barb Beck
Edmonton, Alberta, Canada
-----Original Message-----
From: NBHC ID-FRONTIERS Frontiers of Field Identification
[mailto:BIRDWG01(AT)listserv.arizona.edu]On Behalf Of Lethaby, Nick
Sent: May 24, 2002 1:53 PM
To: BIRDWG01(AT)listserv.arizona.edu
Subject: Re: [BIRDWG01] RFH: audio of poss. Cassin's Vireo - Fort Worth
Based on last winter's experience in Santa Barbara with a Solitary Vireo
that most people were happy was a Blue-headed (it was even banded as such)on
plumage but that sang like a Cassin's, I would agree that it may only be
possible to id extreme individuals.
One point I'm not 100% clear on is whether Cassin's in winter can be
brighter than those seen in spring/summer/fall. Matt's paper indicated that
Cassin's could be similar to Plumbeous when in worn plumage in the spring. I
am wondering if Cassin's in winter are typically brighter and can be
confused more with BHVI, especially if birders aren't really familiar with
BHVI. Certainly in Santa Barbara, we apparently had 2 other birds that
observers thought were similar to the "BHVI" bird. It seems unlikely all 3
were BLVI especially as one sung like a Cassin's. I haven't looked up the
moult info in Pyle, but if Cassin's has a post-fall migration full moult,
one would expect birds in early-mid-winter to be brighter.
-----Original Message-----
From: Martin Reid [mailto:upupa(AT)AIRMAIL.NET]
Sent: Thursday, May 23, 2002 5:50 PM
To: BIRDWG01(AT)listserv.arizona.edu
Subject: Re: [BIRDWG01] RFH: audio of poss. Cassin's Vireo - Fort Worth
Dear All,
I thank David Sibley and Barb Beck for their contributions; these are the
only replies I've received from birders with good experience of singing
CAVI, and I especially value Barb's local experience in the apparent
contact zone.
It seems that even if voice changes in the Solitary complex are clinal,
there might be benchmark points along that cline that could be used to
place any particular individual. Barb Beck is using her personal
experience
to categorize songs into CAVI, intermediate, and BHVI (presumably of the
western group, and thus with some regular burriness?); if we add to this
the "classic" non-burry eastern BHVI and typical PLVI, we end up with five
types.
Presuming the situation to indeed be clinal, there will be some
individuals
that fall between these "points on a scale" - but at least such a scale
would allow the voice of an individual bird to be placed into the scale
fairly accurately.
So, can we define such a scale? - I find myself asking "where would the
audio clips of the Fort Worth bird place it in such a scale?"
Presumably, any individual bird sounding just like CAVi, could actually be
a BHVI from the breeding contact zone that has learned the wrong song -
but
what about vice versa?; all three forms winter in Oaxaca, so a CAVI could
learn even the eastern BHVI song from there - or does this "wrong song"
event only happen to juvs in the natal area?
Thus we seem to have BHVIs that can be non-burry or somewhat burry, plus
any individual suspected vagrant might instead be a "cross-singer" of the
commoner form.... it seems to me that for the purposes of ID-ing potential
vagrants, the voice is at best a supporting feature - something that does
not rule out the common form, no matter how "wrong" it sounds; is this a
reasonable conclusion?.
As to plumage, I'd like to suggest an exercise:- dig out Matt Heindel's
article on the "Solitary" vireos ( BIRDING Dec '96), open it at pages
468/469, then fold the front portion back on itself so that you are
looking
at the bird in fig 12 on page 469 and the bird on the front cover:- which
one has the cleanest demarcation of the throat/auricular? Given that this
is held as just about the strongest out of a bunch of fairly subtle and
overlapping features, I feel that only the most extreme examples (e.g.
Figs
1, 2, 3, 4, 6 and probably 11) could be identified AS VAGRANTS with any
degree of confidence; all the others would surely be "most like xxxx, but
yyyy cannot be ruled out". Keep in mind that I am talking here not of any
individual birder's ability to be right on this, but about how a RBC could
assess a record submission.
The point here is that from a vagrant standpoint, LOTS of these vireos
will
not be firmly identifiable - true?
Regards,
Martin
FYI some images to consider:
http://www.wfo-cbrc.org/cbrc/photos/bhvi1.html - I'd love to know how this
bird is FIRMLY identifiable as a vagrant BHVI, as it seems to fall into
(or
very close to) the overlap zone, to my inexperienced eye. There are no
biometric differences to use (correct?), so are there any in-the-hand
micro-features that are absolutely definitive? I am merely trying to learn
from this example.
http://www.wfo-cbrc.org/cbrc/photos/bhvi2.html
http://rip.physics.unk.edu/NOU/Photographs/CassinVireo.html
http://www.islandnet.com/~rpbo/photos/photo14.html
Martin Reid
Fort Worth, Texas
upupa(AT)airmail.net
http://www.martinreid.com
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[ << | >> | ^^ ]
Subject: Solitary Vireos
From: Matt Heindel <MTHEINDEL(AT)AOL.COM>
Date: 28 May 2002 9:58am
----INCLUDING text/plain MIME SECTION----
Work has kept me from getting into this topic until now, but I saved a few of
the items and will offer a few thoughts. This is a great topic and, as usual,
David has hit this one on the head. There is so much overlap, we must resist
the temptation to move further along this ID limb.
I find this somewhat analogous to the Empidonax issue. We have learned so
much about Empids in the past two decades that an alarming % are identified.
It is illogical to think that errors are not happening with frequency with
this complex. Same with SOVI. We have learned a lot, and we have this
scarcely controllable urge to label these things (me, too!). But, we are on
thin ice once we talk about extralimital sightings.
I can't tell you how many times since my museum research that I have walked
away from birds in the field without putting a name on these things.
Frequently, this is because the bird looks more like the "vagrant" but not
enough to call it out of range. I love seeing these things in the field; I
guess the reality of not being able to identify some in the hand have
encouraged me to do the same in the field. I have found the same with songs,
but have nothing to add to the caution already surfaced here.
Nick asks about the potential for confusion on the two western taxa: it can
happen anytime. I mentioned the worn spring phenomenon as it is the easiest
to blur, but it can happen in winter as I saw in an Orange County (CA) bird
and as must be the case with his bird. And, I remember Kimball collecting one
in summer and, as we stared at it in the hand, we still walked away shrugging
shoulders. This same thing happens with CAVI vs. BHVI. Some specimens are
hard to separate so how would this happen in the field? I recall 3 birds in
the LSU collection that prompted head scratching. And, the same can be said
for the Smithsonian collection: the study answered some questions, but gave
rise to several mysteries.
As for hybrids, there were none in the collections but that is no surprise.
How would one know to look for it? I would be surprised if there was no
hybridization but will watch as others figure that out.
Roberson shared his loral feature with me prior to the article. In general, I
believe it works on bold BHVI, but paradoxically, that is when it is needed
the least. On non adult males, or in comparison to bright CAVI, I think it is
a mark that could be used to add to the equation but nothing to bank on (as
with almost all other features).
The comments of caution are not meant to doom the topic. This is good
discussion; it is just important to remember, x % of extralimital birds will
not be able to be safely identified in the field with today's knowledge.
Green, dingy birds back east, and bold, bright birds showing sharp throat
contrast in the west. Otherwise, the slippery slope has been entered. Have
fun!
Matt Heindel
San Antonio TX
mtheindel(AT)aol.com
----DELETED text/html MIME SECTION----
[ << | >> | ^^ ]
Subject: "Alaskan" Blackpolls
From: Evan Obercian <ewilsono(AT)HOTMAIL.COM>
Date: 28 May 2002 10:23am
IDF,
In Alaska last spring I was struck by the rapidity of the song of Blackpolls
there. Conventional wisdom seems to hold that this song is heard only by
BLPWs in Alaska. As I was hearing it sung by birds seemingly on migration
(by habitat) in Anchorage, I thought it rather odd that this song is given
ONLY in Alaska, because I don't often hear warblers giving alternate songs
before they are on territory (but sometimes I do). If migrants in Alaska
give this song, why not migrants elsewhere bound for Alaska? Well, this
spring I have twice heard the "Alaskan" song type from migrant BLPWs in New
Jersey. That not only contradicts the rumors I've heard previously (that
this song is only given in Alaska) but also raises the question whether or
not I can assume these birds are bound for Alaska. Has anyone heard this
song outside of Alaska, either by migrants or by breeders?
I have not followed the vireo thread too closely. My only comment is that
the frequency-modulated BHVIs in the East that David Sibley refers to could
be at least partly the product of Yellow-throated Vireo influence. I have
occassionaly heard BHVI singing very YTVI-like song phrases and vice-versa.
regards,
Evan Obercian
NJ
_________________________________________________________________
MSN Photos is the easiest way to share and print your photos:
http://photos.msn.com/support/worldwide.aspx
[ << | >> | ^^ ]
Subject: Re: "Alaskan" Blackpolls
From: Evan Obercian <ewilsono(AT)HOTMAIL.COM>
Date: 28 May 2002 6:15pm
IDF,
I've recieved a few comments regarding my Blackpoll question and it occurs
to me that I should have clarified to what I refer when I say "Alaskan"
song-type. Typical Blackpolls, from my experience, give two main song
types: a slow, lethargic-sounding "tsi tsi TSI TSI tsi tsi" and a faster,
more forceful "tsi-si-si-SI-SI-SI-SI-si-si", with some variation within both
song types. I don't know how many notes per second this second song type is
but I would generally describe it as a rapid series of countable notes, not
a trill. The "Alaskan" BLPWs, however, sing a very rapid trill sounding as
fast as e.g. Worm-eating Warbler, almost unrecognizable as the species but
maintaining more-or-less the same quality and characteristic crescendo.
Hope that helps.
Evan Obercian
NJ
_________________________________________________________________
MSN Photos is the easiest way to share and print your photos:
http://photos.msn.com/support/worldwide.aspx
[ << | >> | ^^ ]
Subject: Re: "Alaskan" Blackpolls
From: Eric Preston <eric(AT)ERICWPRESTON.COM>
Date: 28 May 2002 8:21pm
I imagine the recording on the Stokes Western Birds CD is of the "Alaskan"
type you mention, it being a high-pitched trill, and the Peterson and Stokes
Eastern Birds recordings are of the other main song types. I was amazed when
I first heard the version on the Stokes Western CD thinking they must have
made a mistake as I'd never heard a Blackpoll sound like that before. I
don't have the CD guides handy so can't lookup where the recordings were
made.
Eric Preston
Scotts Valley, CA
-----Original Message-----
From: NBHC ID-FRONTIERS Frontiers of Field Identification
[mailto:BIRDWG01(AT)listserv.arizona.edu]On Behalf Of Evan Obercian
Sent: Tuesday, May 28, 2002 6:16 PM
To: BIRDWG01(AT)listserv.arizona.edu
Subject: Re: [BIRDWG01] "Alaskan" Blackpolls
IDF,
I've recieved a few comments regarding my Blackpoll question and it occurs
to me that I should have clarified to what I refer when I say "Alaskan"
song-type. Typical Blackpolls, from my experience, give two main song
types: a slow, lethargic-sounding "tsi tsi TSI TSI tsi tsi" and a faster,
more forceful "tsi-si-si-SI-SI-SI-SI-si-si", with some variation within both
song types. I don't know how many notes per second this second song type is
but I would generally describe it as a rapid series of countable notes, not
a trill. The "Alaskan" BLPWs, however, sing a very rapid trill sounding as
fast as e.g. Worm-eating Warbler, almost unrecognizable as the species but
maintaining more-or-less the same quality and characteristic crescendo.
Hope that helps.
Evan Obercian
NJ
_________________________________________________________________
MSN Photos is the easiest way to share and print your photos:
http://photos.msn.com/support/worldwide.aspx
[ << | >> | ^^ ]
Subject: Re 2 : Common Ringed Plover in Québec now
From: Michel Bertrand <bertrmi(AT)COLBA.NET>
Date: 29 May 2002 10:39am
Harry Hussey has written :
> Did you notice any difference in the loral pattern? The dark
> area meets the bill higher up on Semi-P than on Ringed
> (diagnostic,as far as I know); meets at gape on Ringed.
Yes. That was in the François Grenon's excellent report I refered you to in
my first message, with an URL. The dark area extends to the gape.
The first photos (3) of our Common Ringed Plover are now shown at
http://www.cam.org/~franche/
Note the lack of webbing between inner toes and the other field marks I did
note in my first message.
Harry added :
> Also, a Ringed Plover could stand out as a larger bird
Our bird was a little larger and bulkier than the Semipalmated Plovers
nearby. My first guess would be that it is an hiaticula, not a tundrae. At
first, it appears clearly paler than Semipalmated to me but, later, that was
not so evident. I would say it was somewhat paler (François wrote a little
grayer). There is an important contrast between its black and its brown
parts, a neatly greater contrast than on semipalmatus (it means paler or
different brown, I estimate). Our bird is looking like the photo A of
hiaticula on page 73 in Rosair & Cottridge's *Photographic guide to the
Shorebirds of the World*, but with a broader breast band. It doesn't look
like the slimmer and darker tundrae of photo B which has a narrow eyebrow. I
have not seen enough good photos of tundrae to have a reliable idea of what
this subspecies look like. The small not very well-known population of
Common Ringed Plovers in very northeastern Canada is normally said to be
Charadrius hiaticula hiaticula. It seems to be a double cline in that
species, a west-east cline between the two named subspecies ans a
north-south cline in the nominal subspecies with paler birds in the South
(in Europe). Our bird could be from the northern Canadian populations which
would explains why it is of the hiaticula type without being so pale. But
that's only speculative.
For those of you who have written they want to come, the bird was still at
the same place yesterday (Tuesday), but I still haven't a report for today.
Here are more precise directions. Baie-du-Febvre is on the southshore of
Saint-Laurent river at a little more than 100 km east of Montréal, along
road 132 (you can take road 30 to Sorel and continue on road 132 to
Baie-du-Febvre). At the western limit of Baie-du-Febvre, a dirt road
(Janelle road) goes north from road 132 to
Saint-Laurent river. The Common Ringed Plover is seen among other shorebirds
in a wet field along Janelle road, not far from its end, on the right side.
On Janelle road, you will see, at first, two artificial ponds on your right.
A few phalaropes (one Red-necked and nine Wilson's on Sunday) were in the
second ponds with a lot of ducks including Red-headed Ducks. A little
further, there is a very large natural-looking pond. Ruddy Ducks, Least
Bitterns and many other water-birds nest there. After the pond, the road
tuns left and the field with the Common Ringed Plover is not far.
There are other good birding site along road 132, est of the village, and at
Port-Saint-François (Parc de l'Anse-du-Port) north of Nicolet.
Good luck... Tell me if you see the bird.
MICHEL BERTRAND
Sainte-Julie, Qc
bertrmi(AT)colba.net
[ << | >> | ^^ ]
Subject: Re: "Alaskan" Blackpolls
From: "Michael O'Brien" <obrienm(AT)ALGORITHMS.COM>
Date: 29 May 2002 12:53pm
Evan,
For what it's worth, I just heard one of those "Alaskan"-type Blackpolls in
Cape May the other day. I hear one or two like that most springs in this
region, usually late in the seadon. Whether these birds are headed to Alaska
or are just starting to use an alternate song used by all populations I
don't know. Whatever the case, it seems to be a relatively rarely-head song
here.
Michael O'Brien
West Cape May, NJ
----------
>From: Evan Obercian <ewilsono(AT)HOTMAIL.COM>
>To: BIRDWG01(AT)listserv.arizona.edu
>Subject: [BIRDWG01] "Alaskan" Blackpolls
>Date: Tue, May 28, 2002, 1:23 PM
>
>IDF,
>
>In Alaska last spring I was struck by the rapidity of the song of Blackpolls
>there. Conventional wisdom seems to hold that this song is heard only by
>BLPWs in Alaska. As I was hearing it sung by birds seemingly on migration
>(by habitat) in Anchorage, I thought it rather odd that this song is given
>ONLY in Alaska, because I don't often hear warblers giving alternate songs
>before they are on territory (but sometimes I do). If migrants in Alaska
>give this song, why not migrants elsewhere bound for Alaska? Well, this
>spring I have twice heard the "Alaskan" song type from migrant BLPWs in New
>Jersey. That not only contradicts the rumors I've heard previously (that
>this song is only given in Alaska) but also raises the question whether or
>not I can assume these birds are bound for Alaska. Has anyone heard this
>song outside of Alaska, either by migrants or by breeders?
>
>I have not followed the vireo thread too closely. My only comment is that
>the frequency-modulated BHVIs in the East that David Sibley refers to could
>be at least partly the product of Yellow-throated Vireo influence. I have
>occassionaly heard BHVI singing very YTVI-like song phrases and vice-versa.
>
>regards,
>Evan Obercian
>NJ
>
>_________________________________________________________________
>MSN Photos is the easiest way to share and print your photos:
>http://photos.msn.com/support/worldwide.aspx
>
[ << | >> | ^^ ]
Subject: "Alaskan" Blackpolls
From: LVM <marnmc(AT)GLOBALSERVE.NET>
Date: 29 May 2002 1:28pm
Here in Southern Ontario, on the Niagara Escarpment, I have had Blackpolls
as regular Spring migrants through my property for the past ten years. On
several occasions, I have heard and seen them give an atypical very rapid
buzzy trill, in at least one case, reminiscent of the cadence of a Chipping
Sparrow. I wouldn't necessarily equate the vocalization to that of a
Worm-eating Warbler, but it indeed makes you sit up and take notice.
Cheers,
Lou Marsh
Campbellville ON Canada
[ << | >> | ^^ ]
Subject: Oups !
From: Michel Bertrand <bertrmi(AT)COLBA.NET>
Date: 29 May 2002 9:33pm
I'm just noticing that the message from Harry Hussey to which I have
answered here had not be sent to the list. As I have received two copy of
it, I did assume that one was a direct copy and the other was from the list.
But I see now it was not. Sorry...
MICHEL BERTRAND
Sainte-Julie, Qc
bertrmi(AT)colba.net
[ << | >> | ^^ ]
Subject: Explanation requested: Solitary
Vireos
From: JIm Barton <redwing1986(AT)ATTBI.COM>
Date: 30 May 2002 3:04pm
This is a multi-part message in MIME format.
----INCLUDING text/plain MIME SECTION----
Matt, could you explain "x %" and the intended meaning of the =
incomplete sentences bracketed below? Are "green, dingy birds back =
east" among the "x % not safely identifiable in the east? From the =
photos in your Birding article, and other sources, I would have assumed =
that the latter are CAVI females. =20
I saw one of these green dingy birds a few years ago in Spring in MA =
accompanied by an extremely washed out bird showing very little =
contrast about the lores, head, nape and throat, but a fair amount of =
yellow on the flanks. I have been taking the latter to have been the =
male. In more than 30 years of birding in MA, I have never seen =
"Solitary" Vireos that looked at all like the green dingy bird. I first =
took the washed out bird to be BHVI. but was very unhappy with that =
call, and soon rejected it on seeing an example of the bright expected =
version of the spring bird. In more than 30 years of birding in MA, I =
have never seen a BHVI of similar appearance to the washed out bird.
Yours,
Jim Barton
redwing1986(AT)attbi.com
Cambridge, MA
----- Original Message -----=20
From: Matt Heindel=20
To: BIRDWG01(AT)listserv.arizona.edu=20
Sent: Tuesday, May 28, 2002 12:58 PM
Subject: [BIRDWG01] Solitary Vireos
Snip Snip Snip
it is just important to remember, x % of extralimital birds will not =
be able to be safely identified in the field with today's knowledge. =
[[Green, dingy birds back east, and bold, bright birds showing sharp =
throat contrast in the west. ]] Otherwise, the slippery slope has been =
entered. Have fun!
Matt Heindel
San Antonio TX
mtheindel(AT)aol.com=20
----DELETED text/html MIME SECTION----
[ << | >> | ^^ ]
Subject: Solitary Vireo
From: Matt Heindel <MTHEINDEL(AT)AOL.COM>
Date: 31 May 2002 7:31pm
I responded to Jim Barton's question but unintentionally did not respond to
the list. So, if you followed this far, here is what I wrote with a little
elaboration:
I think the dingy green things in the east are the only safe Cassin's to
claim. The tweener Cassin's might be approached by a 1st spring (second
calendar year) BHVI. A bold CAVI is real trouble. This gets dicey. I just
looked at photos of a hand held bird (from NY) that caused me fits. It is a
tweener and one has to assess how the photos duplicate what is seen in life.
Continuing that notion I have a fresh Cassin's I photographed in east Kern in
early Sep (before most BHVI are moving that far south) that looks far bolder
in pics than it did in life. Everyone has to decide their own litmus barriers
on these tweeners; my capacity to leave them unidentified is rather broad.
But, I would have no hesitation calling an all green Solitary a Cassin's.
I do not have a clue what % of vagrants will be identifiable. I can tell you
I have seen a dozen that I have felt were vagrants but would not call them as
they were in the overlap zone. I recall Jon Dunn and I watching a suspected
Blue-headed in CA one fall and just musing that we wouldn't think twice about
the bird if we were back east, but it was too risky to call it a BHVI out in
CA. The same thing happens with PLVI vs CAVI in CA where PLVI might be
unseasonal but not a vagrant. Some get left alone.
This is such a bizarre problem. I don't use the word hopeless as I find it
rather amusing. But, I do feel many birders are not prepared to walk from
identifications in this complex. The overlap in plumage and song is amazing.
Enjoy these Solitary things even if you don't get to know them on a first
name basis.
Matt Heindel
San Antonio TX
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