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ID-FRONTIERS for March 24-31, 2002
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Messages are displayed in the order they were received.
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| Subject | From | Date | Time |
| Re: Need help IDing a small bird - Redpoll???? | birddog | Sun, 24 Mar 2002 | 1:48pm |
| | Nemuno deltos region | Mon, 25 Mar 2002 | 5:26am |
| Re: Need help IDing a small bird - Redpoll???? | Alfons Willemsen | Mon, 25 Mar 2002 | 9:50am |
| Franklin's Gull Mantle Colour | Tristan Reid | Mon, 25 Mar 2002 | 11:45am |
| Re: Eurasian Wigeon numbers | David Sibley | Mon, 25 Mar 2002 | 1:45pm |
| female wigeon | will russell | Mon, 25 Mar 2002 | 4:45pm |
| Re: Eurasian Wigeon numbers | Bruce Mactavish | Mon, 25 Mar 2002 | 6:04pm |
| Re: genes and mystery gull. | Bruce Mactavish | Mon, 25 Mar 2002 | 7:44pm |
| Re: Hybrids Green-winged x Eurasian teals
(A.carolinensis x crecca) | Millington/BIS | Tue, 26 Mar 2002 | 2:30am |
| Re: Eurasian/American Wigeon and female birds | Harry Hussey | Tue, 26 Mar 2002 | 5:59am |
| Re: Eurasian Wigeon numbers and hybrids | Wayne C. Weber | Tue, 26 Mar 2002 | 10:56am |
| Re: Eurasian Wigeon numbers and hybrids | Martin Reid | Tue, 26 Mar 2002 | 11:44am |
| Re: Eurasian Wigeon numbers and hybrids | David Beaudette | Tue, 26 Mar 2002 | 12:45pm |
| FW: Hybrids Green-winged x Eurasian
teals (A.carolinensis x crecca) | Colin Bradshaw | Tue, 26 Mar 2002 | 1:50pm |
| Re: female wigeon | Norman D.van Swelm | Tue, 26 Mar 2002 | 1:55pm |
| Re: Eurasian Wigeon numbers and hybrids | Lethaby, Nick | Tue, 26 Mar 2002 | 2:02pm |
| Re: Eurasian Wigeon numbers and hybrids | Peter Adriaens | Tue, 26 Mar 2002 | 2:17pm |
| Black vs. Gray-bellied Brant | pabuckley | Tue, 26 Mar 2002 | 3:16pm |
| Re: Eurasian Wigeon numbers and hybrids | Michael Dossett | Tue, 26 Mar 2002 | 5:00pm |
| Re: Eurasian Wigeon numbers | Jon King | Tue, 26 Mar 2002 | 8:44pm |
| Re: FW: Hybrids Green-winged x
Eurasian teals (A.carolinensis x crecca) | Millington/BIS | Wed, 27 Mar 2002 | 3:46am |
| Re: Hybrids Green-winged x Eurasian teals | Laurent Raty | Wed, 27 Mar 2002 | 4:45am |
| Jack Snipe {Lymnocryptes minimus} age help | Bill Elrick | Wed, 27 Mar 2002 | 7:05am |
| Wigeon again | will russell | Wed, 27 Mar 2002 | 8:24am |
| GRAY-BELLIED BRANT | Wayne C. Weber | Wed, 27 Mar 2002 | 9:34am |
| Hybrid teals and wigeon | =?iso-8859-1?Q?Ricar | Wed, 27 Mar 2002 | 10:46am |
| wigeon plumage changes | Paul Lehman | Wed, 27 Mar 2002 | 2:41pm |
| Hybrid waterfowl threads | Angus Wilson | Wed, 27 Mar 2002 | 8:29pm |
| Re: Hybrid waterfowl threads | birddog | Wed, 27 Mar 2002 | 9:03pm |
| Teal variation | Martin Reid | Thu, 28 Mar 2002 | 7:30am |
| Re: Teal variation | Alain FOSSE (Angers, | Thu, 28 Mar 2002 | 9:23am |
| Re: Mystery Gull | Robert H. Lewis | Thu, 28 Mar 2002 | 10:44am |
| Re: Teal variation | Peter Adriaens | Thu, 28 Mar 2002 | 10:48am |
| Peters World checklist | ian paulsen | Fri, 29 Mar 2002 | 12:18pm |
| yellow-legged Great Black-backed Gulls | Bruce Mactavish | Sun, 31 Mar 2002 | 5:58am |
| Aberrant Franklin's or Hybrid? | Tristan Reid | Sun, 31 Mar 2002 | 6:45am |
| UNSUBSCRIBE | Janus Andersen | Sun, 31 Mar 2002 | 7:13am |
| Re: Aberrant Franklin's or Hybrid? | Millington/BIS | Sun, 31 Mar 2002 | 8:28am |
| Leg Color and Spring Bloom in Ring-billed Gulls | John Idzikowski | Sun, 31 Mar 2002 | 10:57am |
| Re: yellow-legged Great Black-backed Gulls | Norman D.van Swelm | Sun, 31 Mar 2002 | 3:53pm |
| Teal and scoter variation | Norman D.van Swelm | Sun, 31 Mar 2002 | 4:21pm |
| Re: Eurasian Wigeon numbers and hybrids | Steven Mlodinow | Sun, 31 Mar 2002 | 6:07pm |
| Re: FW: Hybrids Green-winged x
Eurasian teals (A.caroli... | Steven Mlodinow | Sun, 31 Mar 2002 | 6:14pm |
|
To use email addresses replace '(AT)' with '@'.
This is done to confuse the spam 'bots.
|
[ << | >> | ^^ ]
Subject: Re: Need help IDing a small bird - Redpoll????
From: birddog <birddog(AT)SNET.NET>
Date: 24 Mar 2002 1:48pm
Could this be a European Goldfinch? The images are not clear but it seems
consistent with that species.
Mark Szantyr
----- Original Message -----
From: "Jamie Wapisay" <jwapisay(AT)HOTMAIL.COM>
To: <BIRDWG01(AT)listserv.arizona.edu>
Sent: Sunday, March 24, 2002 12:08 AM
Subject: [BIRDWG01] Need help IDing a small bird - Redpoll????
> I have pictures of this bird on my homepage at
http://jamiespence.myknet.org
> I think it may be a redpoll but it looks a little different. If anyone can
> help me out it would be greatly appreciated.
>
> _________________________________________________________________
> Send and receive Hotmail on your mobile device: http://mobile.msn.com
>
[ << | >> | ^^ ]
Subject:
From: Nemuno deltos regioninis parkas <ndrp(AT)SILUTE.OMNITEL.NET>
Date: 25 Mar 2002 5:26am
This is a multi-part message in MIME format.
----INCLUDING text/plain MIME SECTION----
unsubscribe
----DELETED text/html MIME SECTION----
[ << | >> | ^^ ]
Subject: Re: Need help IDing a small bird - Redpoll????
From: Alfons Willemsen <a.willemsen(AT)SKYNET.BE>
Date: 25 Mar 2002 9:50am
This is a multi-part message in MIME format.
----INCLUDING text/plain MIME SECTION----
I think its a Carduelis carduelis.
Greetings Fons
( =B0)>
/( )\
/ \/ \
! ! ! NIEUW E-MAIL ADRES a.willemsen(AT)skynet.be NEW E-MAIL =
ADDRESS ! ! ! =20
Dagelijks vogelsringen van 06.00 tot 13.00 u. in de periode 20 juni/20 =
november.
Ringplaats;Prov.Domein Broek Denaeyer, 51.04N-04.22E, Willebroek, =
Antwerpen, Belgi=EB
KBIN - Ringers ID : 1395=20
http://proaction.tripod.com/team/=20
www.voc-malderen.yucom.be
< Vivat, crescat, floreat Ornithologia >
Wij moeten streven naar het behoud van de ons omringende natuur.
Wij zijn het aan onszelf verplicht.
Om haar ongeschonden door te geven aan de komende generaties.
----- Original Message -----=20
From: "Jamie Wapisay" <jwapisay(AT)HOTMAIL.COM>
To: <BIRDWG01(AT)listserv.arizona.edu>
Sent: Sunday, March 24, 2002 6:08 AM
Subject: [BIRDWG01] Need help IDing a small bird - Redpoll????
> I have pictures of this bird on my homepage at =
http://jamiespence.myknet.org
> I think it may be a redpoll but it looks a little different. If anyone =
can
> help me out it would be greatly appreciated.
>=20
> _________________________________________________________________
> Send and receive Hotmail on your mobile device: http://mobile.msn.com
>=20
----DELETED text/html MIME SECTION----
[ << | >> | ^^ ]
Subject: Franklin's Gull Mantle Colour
From: Tristan Reid <brown.flycatcher(AT)BTOPENWORLD.COM>
Date: 25 Mar 2002 11:45am
Hi,
I am interested in finding out how variable (If at all) the Mantle
Colouration of Franklin's Gull (Larus pipixcan) is. For example are there
variants within the population that show mantle colouration similar to that
of Common Gull (Larus canus)?
If anyone with good experience of Franklin's Gull can help me with this
enquiry please email me on brown.flycatcher(AT)btopenworld.com
Thank you in advance,
Regards
Tristan Reid
http://groups.yahoo.com/group/BirdingCumbria
The Email Group for Birders in Cumbria
[ << | >> | ^^ ]
Subject: Re: Eurasian Wigeon numbers
From: David Sibley <dsibley(AT)SHORE.NET>
Date: 25 Mar 2002 1:45pm
Hi All,
It is impossible to state any ratio of female to male Eurasian Wigeon
without doing some SERIOUS looking. I think it's safe to say that none of us
has ever looked carefully enough, at enough wigeon, to make any comments
about the real sex ratio. Just because we haven't picked out as many females
doesn't mean they aren't there. This question might be resolved by someone
taking the time to look at relatively small groups of wigeon (100 might be
manageable) at very close range, and checking each and every individual. At
a park in Victoria, BC last fall I looked at about 50 wigeon at distances
ranging from 10 to 30 feet. There were no male Eurasians but I picked out
one female Eurasian quickly, and 5 minutes later a second one. Around
Bolinas, California ten years ago I found about half as many female as male
Eurasians, and my sense was that I was just missing the females because many
wigeon were just too far away to check. I would be willing to bet that given
a thorough and objective study one would find equal numbers of males and
females.
I am also intrigued by the discussion of hybrids, since male hybrids are
generally pretty obvious. My experience in eastern North America is that
there are very few records of hybrids. I've seen one, and heard of a few
others. On the other hand, California supports a high percentage of hybrids
in winter, and I've seen hybrids at many other places along the west coast
from Southern California to Alaska. My experience ten years ago(I'll have to
be a bit vague now) was that at Bolinas Lagoon there were about 2 hybrids
for every 3 pure males -- nearly equal numbers, the pure birds just slightly
more numerous. This is in contrast to the situation in eastern North
America, and now, it would seem, in contrast to the situation in BC. Is this
a case of the BC hybrids being overlooked? or a real difference in the
winter range of hybrids?
David Sibley
Concord, MA
----- Original Message -----
From: "Jon King" <king(AT)PRBO.ORG>
To: <BIRDWG01(AT)listserv.arizona.edu>
Sent: Friday, March 22, 2002 12:43 PM
Subject: Re: [BIRDWG01] Eurasian Wigeon numbers
> Ian, Steve, et al.,
>
> Coming from a British perspective, I have always found this subject to
> be especially interesting. On my most recent trip to WA and BC, one of
> my counts was of 56 Eurasian Wigeons (40 males, 16 females) and six
> hybrid males among 590 American Wigeons at Deltaport, BC, on 30 Nov
> 2001. Although I was impressed more by the relative frequency of
> Eurasian Wigeon (about 8.5 percent) rather than the absolute count, when
> I mentioned it to Tom Plath and Rick Toochin, both suggested that recent
> counts in excess of 200 Eurasian Wigeons had been made at individual
> sites in the Deltaport-Tsawassen-Point Roberts areas.
>
> >From a historical perspective, the count of 21 on the Victoria CBC in
> Dec 1984 (Campbell et al. 1990, The Birds of British Columbia, vol.1)
> was then the all-time North American high count for Eurasian Wigeon!
>
> References such as BWP and Wildfowl mention nothing about differential
> dispersal of male and female Eurasian Wigeon (other than males moving
> from breeding to moulting areas earlier than females, prior to autumn
> migration). Migration texts I checked implied that in wildfowl the sexes
> disperse similar distances. Of course dispersion distance is often
> related to body size, resulting in females moving on average slightly
> further than males in most sexually size dimorphic species. I suspect
> the exact situation regarding wigeon migration may not be known.
>
> Unfortunately, the true numbers of Eurasian Wigeon and hybrids are
> obscured by most observers' understandable reluctance to identify
> females. Even very practised observers often find it a daunting task in
> North America when confronted with large mixed flocks, but in my
> experience females are indeed present, at a frequency of at least one to
> every 2-4 males (depending on site, date, conditions, etc.).
>
> Cheers, Jon.
>
>
[ << | >> | ^^ ]
Subject: female wigeon
From: will russell <russellbw(AT)EARTHLINK.NET>
Date: 25 Mar 2002 4:45pm
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I agree with David Sibley's comment that finding female Eurasian Wigeon =
can take some close study but it also occurs to me that the wigeon may =
do some of the job for us. Literature suggests that more than 80% of =
female wigeon are paired by March and assuming that these species mate =
assortively (i.e female Eurasian Wigeon prefer male Eurasian Wigeon, if =
available...perhaps a large asumption), it should be possible to focus =
on only the females associating with male Eurasians. In any event, it =
would be interesting to know just who was paired with the Eurasian =
males, if anyone.
Will Russell
russellbw(AT)earthlink.net
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[ << | >> | ^^ ]
Subject: Re: Eurasian Wigeon numbers
From: Bruce Mactavish <bruce.mactavish1(AT)NF.SYMPATICO.CA>
Date: 25 Mar 2002 6:04pm
In eastern Newfoundland both American and Eurasian Wigeon are scarce.
Wigeons are attracted to the large numbers of wild, but tame, bread
feeding Black Ducks, Mallards and Northern Pintail in St. John's. Soon
they also become tame allowing microscopic study. All wigeons are
identified in St. John's. The annual autumn tally averages 8-15+ wigeons
with Eurasians usually outnumbering American. Most birds arrive in
October and November. Others appear at freeze up in late December. The
latter likely coming into St. John's from nearby areas. Most birds end
up toughing out a St. John's winter surviving on bread handouts with the
hundreds of local dabblers that have adapted to this life style. Among
Eurasian Wigeons adult males are a distinct minority. The large majority
of birds arriving in October and November are brown female-like. By late
November immature males may show a few gray flank feathers or hints of
male orange on the head. By Christmas it is clear which of the brown
Eur. Wigeons are males. Through January and February they slowly attain
the full gray flanks and orange heads similar to an adult male. The
ratio of females to males is never less than 60:40. Imm males
outnumbering adult male at least 3:1.
Eur. Wigeons began a dramatic increase in Newfoundland and Atlantic
Canada in the late 1980s. These are thought to be Icelandic birds. There
is some banding evidence to support this. Over the winter St. John's
wigeons form pairs. While each species prefers their own kind there are
frequent mixed pairings. There have been no suspect wigeon hybrids to
date. Tufted Ducks followed a similar pattern of increase in
Newfoundland. It was several years after the influx began before we
identified a male. Males seem to be increasing, but like Eur. Wigeons
females always outnumber males. Five male and 6 female Tufteds wintered
in St. John's this year.
The Iceland source of Eur. Wigeon and Tufted Ducks may extend only to
Atlantic Canada like most of the population of eastern North American
Black-headed Gulls and Common Gulls. Tufted Ducks and Eur. Wigeons have
for 50+ years, without a huge change, been routine in small numbers in
Massachusetts to New Jersey area. The main source of these birds is
probably Alaska and beyond. Many of these could be old birds with a
tradition of wintering in the US Atlantic. Adult males therefore would
be relatively more plentiful and easy to identify earlier in the season.
The majority of the Newfoundland birds seem to be pioneering wanderlust
1st year birds with very few suspected returnees.
Bruce Mactavish
St. John's, Newfoundland
Canada
bruce.mactavish1(AT)nf.sympatico.ca
[ << | >> | ^^ ]
Subject: Re: genes and mystery gull.
From: Bruce Mactavish <bruce.mactavish1(AT)NF.SYMPATICO.CA>
Date: 25 Mar 2002 7:44pm
Gulls of the same species wearing slightly different genes can produce
different looking hybrid offspring. I see three distinctly different
looking groups of hybrid Glaucous x Herring Gulls.
1) European
2) Eastern North America
3) Mackenzie River delta (Northwest Territories, Canada)
I'll use 1st winters as examples since most hybrid GLGUxHEGU identified
are this age. European birds typically look like 1st winter argentatus
Herring Gulls with a bag of flour thrown over them. Bills blackish or
with pale base, generally without the classic pink bill dipped in ink
look. Eastern North America birds typically look like Glaucous Gulls
including classic bill pattern, but with tail band, outer primaries and
secondary bar obviously too dark. Mackenzie River delta birds have much
wider range of plumages. None are like classic eastern North American
birds. Many are similar to European hybrids. In general a hodgepodge of
variations that can look similar to kumlieni, thayeri, very pale
smithsonianus, or oddly dark Glaucous. At least 10-20% of the gulls at
the Inuvik dump in the Mackenzie River delta in the summer of 2001 were
hybrid GLGUxHEGU.
These three groups of birds involve different combinations of two
recognized subspecies of both Herring Gull and Glaucous Gull.
1) Larus a. argentatus x Larus h. hyperboreus
2) Larus a. smithsonianus x Larus h. hyperboreus
3) Larus a. smithsonianus x Larus h. barrovianus
There are suggestions that these combinations involve six distinct
subspecies. European Larus h. hyperboreus differ from eastern North
American birds by adults having heavier head streaking and first winters
being a little darker. The adult Larus a. smithsonianus breeding in the
Mackenzie River Delta were smaller, darker above and with more black in
the wing tip than Atlantic Canada breeding birds.
The point of this message is to say that different populations or
subspecies of a single species can produce different looking hybrids
when mixed with another species.
The Illinois bird doesn't look like a hybrid GLGUxHEGU. The very black
bill looks wrong for even a smithsonianus in mid February. Pale first
winter gulls with bills this dark are Thayer's, Iceland (kumlieni) and
Glaucous-winged. Anyone of these combined with a smithsonianus might
produce a genotype hybrid that looks like this.
Bruce Mactavish
St. John's, Newfoundland
Canada
bruce.mactavish1(AT)nf.sympatico.ca
[ << | >> | ^^ ]
Subject: Re: Hybrids Green-winged x Eurasian teals
(A.carolinensis x crecca)
From: Millington/BIS <sales(AT)birdingworld.co.uk>
Date: 26 Mar 2002 2:30am
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----INCLUDING text/plain MIME SECTION----
Hi
Just to clarify that the percentage of hybrid Green-winged X Common Teal =
in Europe is extremely low.
Carolinensis is purely a vagrant (the nearest breeding range is a whole =
continent or ocean away in either direction), yet it is surprisingly =
common.=20
About 25 drakes per month have been seen in Britain alone so far this =
year (2002), and others have been reported from mainland Europe.=20
Allowing for overlap and returning birds, over 50 drakes might =
conservatively be expected in Britain during the year, with 25 more in =
Europe.
(Counting unidentified females, that makes at least 150 Green-winged =
Teals in Europe in a year).
However, despite there being little chance of these Green-winged Teal =
getting ' back home' to breed,=20
very few hybrids are reported; less than three a year in Europe, in =
fact...
The ratio of pure male carolinensis to male carolinensis X crecca =
hybrids in Europe is therefore about 25 : 1 (or maybe even 50 : 1).
One has been seen in Spain recently.
American Wigeon is a scarcer vagrant in Europe, but hybrids are seen in =
small numbers. I don't have a ratio, but I would guess there is a higher =
percentage of hybrid wigeon compared to pure American Wigeons than is =
the case in Teal =20
(A male hybrid was in Norfolk recently)
cheers
Richard
sales(AT)birdingworld.co.uk
(Birding World, Books for Birders & Birdline)
Bird Information Service, Stonerunner, Coast Road,
Cley next the Sea, Holt, Norfolk, NR25 7RZ, UK
..................................
REF:
11 March 2002 01:28
Overall, I think the ration of Common Teal to hybrids is about 3:1 in =
the Pac NW.
And my estimate for Eur Wigeon to hybrid wigeon is about 20:1.
Steven Mlodinow
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[ << | >> | ^^ ]
Subject: Re: Eurasian/American Wigeon and female birds
From: Harry Hussey <hhussey3(AT)YAHOO.COM>
Date: 26 Mar 2002 5:59am
Hi all,
Will Russell wrote:"Literature suggests that more
than 80% of female wigeon are paired by March and
assuming that these species mate assortively (i.e
female Eurasian Wigeon prefer male Eurasian Wigeon,
if available...perhaps a large asumption), it should
be possible to focus on only the females associating
with male Eurasians."
Interestingly enough,this January I found 2 male
American Wigeon in the flock of Eurasians at
Timoleague,Co.Cork(Ireland).A female bird which was
associating closely with one of the males showed many
features of American,but on the day I was unable to
clinch the ID(didn't see the axilliaries).The bird was
seen well subsequently by a visiting birder and
identified as a female American,so while the fact that
these birds are paired up can't be taken as proof of
their ID,it may well be a good indication of what the
females in question are.
Harry Hussey,Cork,Ireland
__________________________________________________
Do You Yahoo!?
Yahoo! Movies - coverage of the 74th Academy Awards®
http://movies.yahoo.com/
[ << | >> | ^^ ]
Subject: Re: Eurasian Wigeon numbers and hybrids
From: "Wayne C. Weber" <contopus(AT)SHAW.CA>
Date: 26 Mar 2002 10:56am
Bird ID People,
I am astounded by the remarks of Steve Mlodinow, who reports seeing 5
hybrid male AMERICAN x EURASIAN WIGEON in a flock of 2000 wigeon on
the Samish Flats, WA; Jon King, who reports seeing 6 hybrid male
wigeon among only about 650 wigeon at Delta, BC; and especially those
of David Sibley, who reports seeing "about 2 hybrids for every 3 pure
males" at Bolinas Lagoon, CA.
I have studied birds (including wigeon) intensively for 35 years in
the Pacific Northwest, mainly in the Vancouver, BC area and in
northwestern Washington. In that time, I have scanned wigeon flocks
hundreds of times looking for EURASIAN WIGEON and hybrids. I have
never seen more than one hybrid male wigeon at once, although I have
seen more than 40 pure Eurasians in a flock several times.
Until recently, hybrid wigeon were considered to be one of the rarest
dabbling duck hybrids in North America. In 1974, I found and carefully
described a hybrid wigeon that I discovered on the Vancouver, BC
Christmas Bird Count. At that time, to the best of my knowledge, only
two such hybrids had ever been reported previously in North America.
Despite my careful notes, the CBC Regional Editor at the time
questioned the identification and refused to publish the record!!
I would caution all observers to be careful in identifying supposed
hybrids. Pure Eurasian Wigeon CAN sometimes show some green on the
sides of the head where male Americans have a green patch. An
identification as a hybrid should be based on several characters
(colour of head overall, colour of crown, colour of back, colour of
flanks. call-note), and not just on whether there is some green on the
sides of the head.
At the same time, I clearly need to put more effort into identifying
female Eurasian Wigeon. I have identified rufous-morph females on a
number of occasions, but I have subscribed to the once-widespread
philosophy that gray-morph females were not safely identifiable in the
field. Clearly, some gray-morph females can be safely identified, bit
it seems that others cannot, at least at the distances and under the
conditions in which we usually see them.
As for numbers of Eurasians, there has been a steady and impressive
increase in the numbers in the Pacific Northwest since I first began
birding the Vancouver area in the late 1960s. This increase was well
documented by Mike Edgell in a paper in the Journal of Biogeography
(Vol. 11, pages 27-39, 1984), and has continued unabated since that
time. However, Jon King's count of 40 male Eurasians and 16 females
among 590 American Wigeon at Delta, BC in Nov. 2001 is exceptional. I
bird this area frequently, and a ratio of 1 or 2 male Eurasians per
100 Americans (or 2 to 4% of the total number of wigeon, assuming that
the sex ratio is about equal) is more typical.
Clearly, we all need to be more careful in identifying female Eurasian
Wigeon and in identifying supposed hybrid males. I have seen nothing
yet to convince me that American x Eurasian Wigeon is anything other
than a very rare hybrid in North America. As I mentioned in a message
to this group on March 19th, I have observed hybrid EURASIAN x
AMERICAN GREEN-WINGED TEAL in the Vancouver area far more often than
hybrid wigeon (and have several times seen 2 or 3 hybrid teal in the
same flock), even though the pure Eurasian form (COMMON TEAL, if you
prefer) is much scarcer than EURASIAN WIGEON.
Wayne C. Weber
Kamloops and Delta, BC
contopus(AT)shaw.ca
(Vancouver, BC CBC compiler, 1973-1994)
----- Original Message -----
From: David Sibley <dsibley(AT)SHORE.NET>
To: <BIRDWG01(AT)listserv.arizona.edu>
Sent: Monday, March 25, 2002 11:48 AM
Subject: Re: [BIRDWG01] Eurasian Wigeon numbers
Hi All,
It is impossible to state any ratio of female to male Eurasian Wigeon
without doing some SERIOUS looking. I think it's safe to say that none
of us
has ever looked carefully enough, at enough wigeon, to make any
comments
about the real sex ratio. Just because we haven't picked out as many
females doesn't mean they aren't there. This question might be
resolved by someone taking the time to look at relatively small groups
of wigeon (100 might be manageable) at very close range, and checking
each and every individual. At a park in Victoria, BC last fall I
looked at about 50 wigeon at distances ranging from 10 to 30 feet.
There were no male Eurasians but I picked out one female Eurasian
quickly, and 5 minutes later a second one. Around Bolinas, California
ten years ago I found about half as many female as male Eurasians, and
my sense was that I was just missing the females because many wigeon
were just too far away to check. I would be willing to bet that given
a thorough and objective study one would find equal numbers of males
and females.
I am also intrigued by the discussion of hybrids, since male hybrids
are
generally pretty obvious. My experience in eastern North America is
that
there are very few records of hybrids. I've seen one, and heard of a
few
others. On the other hand, California supports a high percentage of
hybrids
in winter, and I've seen hybrids at many other places along the west
coast
from Southern California to Alaska. My experience ten years ago(I'll
have to
be a bit vague now) was that at Bolinas Lagoon there were about 2
hybrids
for every 3 pure males -- nearly equal numbers, the pure birds just
slightly
more numerous. This is in contrast to the situation in eastern North
America, and now, it would seem, in contrast to the situation in BC.
Is this
a case of the BC hybrids being overlooked? or a real difference in the
winter range of hybrids?
David Sibley
Concord, MA
[ << | >> | ^^ ]
Subject: Re: Eurasian Wigeon numbers and hybrids
From: Martin Reid <upupa(AT)AIRMAIL.NET>
Date: 26 Mar 2002 11:44am
Dear all,
I've followed this thread with great interest, and feel that Wayne's point
about using caution when identifying hybrids is well-made.
But surely this applies to teal, also; what criteria are being used to
identify "hybrid" teals?
Only males are involved in this case, as there don't seem to be any
reliable characters for separating pure crecca/nimia from carolinensis, let
alone a female hybrid (please enlighten me if you feel I'm wrong on this).
The most obvious feature seems to be the presence of the vertical shoulder
line (VSL) and the lateral scapular line (LSL), but I wonder if there are
any other signs of mixed genes?: do birds exhibiting VSL + LSL otherwise
look like a normal crecca/nimia, or normal carolinensis? It might be hard
to decide, given that the only other differences are limited to the
strength of vermiculations and facial lines; has anyone seen such a
"hybrid" that has strong vermiculations plus dull face lines (i.e. mixed
characters), or the reverse?
I don't know the answers to these questions, but I'll indulge in a bit of
speculation (again):
Keep in mind that there is some good genetic evidence that Baikal Teal may
be closer in plumage to the ancestral form than any other living dabbler,
and that Baikal males have a VSL. Could it be possible that in some
populations of crecca (perhaps those closest to Baikal Teal in breeding
range?), some individuals produce a "throwback" feature in their plumage,
that manifests itself as a partial (or even full) VSL? Might it be, then,
that some of the birds identified as hybrids could be pure creccas that
have this throwback feature expressed in their plumage? might the imbalance
in presumed hybrids between western North America and Europe be due to the
higher frequency of such throwbacks in the donor population of creccas that
reach NW North America?
Just a thought.
Martin
Martin Reid
Fort Worth, Texas
upupa(AT)airmail.net
http://www.martinreid.com
[ << | >> | ^^ ]
Subject: Re: Eurasian Wigeon numbers and hybrids
From: David Beaudette <drtbrdr(AT)EARTHLINK.NET>
Date: 26 Mar 2002 12:45pm
Dear ID Birders,
I was curious about Wayne Webers remark that "I would caution all observers
to be careful in identifying supposed
hybrids. Pure Eurasian Wigeon CAN sometimes show some green on the sides of
the head where male Americans have a green patch."
My question is: How do we know that a Eurasian Wigeon with green on the
sides of the head is a pure Eurasian?
Good Birding,
Dave Beaudette
Wenatchee, WA
drtbrdr(AT)earthlink.net
-----Original Message-----
From: Wayne C. Weber <contopus(AT)SHAW.CA>
To: BIRDWG01(AT)listserv.arizona.edu <BIRDWG01(AT)listserv.arizona.edu>
Date: Tuesday, March 26, 2002 9:56 AM
Subject: Re: [BIRDWG01] Eurasian Wigeon numbers and hybrids
Bird ID People,
I am astounded by the remarks of Steve Mlodinow, who reports seeing 5
hybrid male AMERICAN x EURASIAN WIGEON in a flock of 2000 wigeon on
the Samish Flats, WA; Jon King, who reports seeing 6 hybrid male
wigeon among only about 650 wigeon at Delta, BC; and especially those
of David Sibley, who reports seeing "about 2 hybrids for every 3 pure
males" at Bolinas Lagoon, CA.
I have studied birds (including wigeon) intensively for 35 years in
the Pacific Northwest, mainly in the Vancouver, BC area and in
northwestern Washington. In that time, I have scanned wigeon flocks
hundreds of times looking for EURASIAN WIGEON and hybrids. I have
never seen more than one hybrid male wigeon at once, although I have
seen more than 40 pure Eurasians in a flock several times.
Until recently, hybrid wigeon were considered to be one of the rarest
dabbling duck hybrids in North America. In 1974, I found and carefully
described a hybrid wigeon that I discovered on the Vancouver, BC
Christmas Bird Count. At that time, to the best of my knowledge, only
two such hybrids had ever been reported previously in North America.
Despite my careful notes, the CBC Regional Editor at the time
questioned the identification and refused to publish the record!!
I would caution all observers to be careful in identifying supposed
hybrids. Pure Eurasian Wigeon CAN sometimes show some green on the
sides of the head where male Americans have a green patch. An
identification as a hybrid should be based on several characters
(colour of head overall, colour of crown, colour of back, colour of
flanks. call-note), and not just on whether there is some green on the
sides of the head.
At the same time, I clearly need to put more effort into identifying
female Eurasian Wigeon. I have identified rufous-morph females on a
number of occasions, but I have subscribed to the once-widespread
philosophy that gray-morph females were not safely identifiable in the
field. Clearly, some gray-morph females can be safely identified, bit
it seems that others cannot, at least at the distances and under the
conditions in which we usually see them.
As for numbers of Eurasians, there has been a steady and impressive
increase in the numbers in the Pacific Northwest since I first began
birding the Vancouver area in the late 1960s. This increase was well
documented by Mike Edgell in a paper in the Journal of Biogeography
(Vol. 11, pages 27-39, 1984), and has continued unabated since that
time. However, Jon King's count of 40 male Eurasians and 16 females
among 590 American Wigeon at Delta, BC in Nov. 2001 is exceptional. I
bird this area frequently, and a ratio of 1 or 2 male Eurasians per
100 Americans (or 2 to 4% of the total number of wigeon, assuming that
the sex ratio is about equal) is more typical.
Clearly, we all need to be more careful in identifying female Eurasian
Wigeon and in identifying supposed hybrid males. I have seen nothing
yet to convince me that American x Eurasian Wigeon is anything other
than a very rare hybrid in North America. As I mentioned in a message
to this group on March 19th, I have observed hybrid EURASIAN x
AMERICAN GREEN-WINGED TEAL in the Vancouver area far more often than
hybrid wigeon (and have several times seen 2 or 3 hybrid teal in the
same flock), even though the pure Eurasian form (COMMON TEAL, if you
prefer) is much scarcer than EURASIAN WIGEON.
Wayne C. Weber
Kamloops and Delta, BC
contopus(AT)shaw.ca
(Vancouver, BC CBC compiler, 1973-1994)
----- Original Message -----
From: David Sibley <dsibley(AT)SHORE.NET>
To: <BIRDWG01(AT)listserv.arizona.edu>
Sent: Monday, March 25, 2002 11:48 AM
Subject: Re: [BIRDWG01] Eurasian Wigeon numbers
Hi All,
It is impossible to state any ratio of female to male Eurasian Wigeon
without doing some SERIOUS looking. I think it's safe to say that none
of us
has ever looked carefully enough, at enough wigeon, to make any
comments
about the real sex ratio. Just because we haven't picked out as many
females doesn't mean they aren't there. This question might be
resolved by someone taking the time to look at relatively small groups
of wigeon (100 might be manageable) at very close range, and checking
each and every individual. At a park in Victoria, BC last fall I
looked at about 50 wigeon at distances ranging from 10 to 30 feet.
There were no male Eurasians but I picked out one female Eurasian
quickly, and 5 minutes later a second one. Around Bolinas, California
ten years ago I found about half as many female as male Eurasians, and
my sense was that I was just missing the females because many wigeon
were just too far away to check. I would be willing to bet that given
a thorough and objective study one would find equal numbers of males
and females.
I am also intrigued by the discussion of hybrids, since male hybrids
are
generally pretty obvious. My experience in eastern North America is
that
there are very few records of hybrids. I've seen one, and heard of a
few
others. On the other hand, California supports a high percentage of
hybrids
in winter, and I've seen hybrids at many other places along the west
coast
from Southern California to Alaska. My experience ten years ago(I'll
have to
be a bit vague now) was that at Bolinas Lagoon there were about 2
hybrids
for every 3 pure males -- nearly equal numbers, the pure birds just
slightly
more numerous. This is in contrast to the situation in eastern North
America, and now, it would seem, in contrast to the situation in BC.
Is this
a case of the BC hybrids being overlooked? or a real difference in the
winter range of hybrids?
David Sibley
Concord, MA
[ << | >> | ^^ ]
Subject: FW: Hybrids Green-winged x Eurasian
teals (A.carolinensis x crecca)
From: Colin Bradshaw <drcolin.bradshaw(AT)btinternet.com>
Date: 26 Mar 2002 1:50pm
This is a multi-part message in MIME format.
----INCLUDING text/plain MIME SECTION----
-----Original Message-----
From: Colin Bradshaw [mailto:drcolin.bradshaw(AT)btinternet.com]
Sent: 26 March 2002 20:34 PM
To: Millington/BIS
Subject: RE: [BIRDWG01] Hybrids Green-winged x Eurasian teals
(A.carolinensis x crecca)
I think you need to be wary of these figures as, of course, it may be that
people are less adept at identifying hybrid GW x European Teal than they are
Am W x EW hybrids. This could be for two reasons. The first is that there
are more distinct differences between the two species of Wigeon whilst the
flank/head pattern differences of the Teal is relatively subtle.
More likely is the fact that, in the UK, many people seem to scrutinise
Wigeon flock looking for 'Yanks' but I've seen few people do the same for
Teal flocks
Colin Bradshaw
-----Original Message-----
From: NBHC ID-FRONTIERS Frontiers of Field Identification
[mailto:BIRDWG01(AT)listserv.arizona.edu]On Behalf Of Millington/BIS
Sent: 26 March 2002 9:30 AM
To: BIRDWG01(AT)listserv.arizona.edu
Subject: Re: [BIRDWG01] Hybrids Green-winged x Eurasian teals
(A.carolinensis x crecca)
Hi
Just to clarify that the percentage of hybrid Green-winged X Common Teal
in Europe is extremely low.
Carolinensis is purely a vagrant (the nearest breeding range is a whole
continent or ocean away in either direction), yet it is surprisingly common.
About 25 drakes per month have been seen in Britain alone so far this year
(2002), and others have been reported from mainland Europe.
Allowing for overlap and returning birds, over 50 drakes might
conservatively be expected in Britain during the year, with 25 more in
Europe.
(Counting unidentified females, that makes at least 150 Green-winged Teals
in Europe in a year).
However, despite there being little chance of these Green-winged Teal
getting ' back home' to breed,
very few hybrids are reported; less than three a year in Europe, in
fact...
The ratio of pure male carolinensis to male carolinensis X crecca hybrids
in Europe is therefore about 25 : 1 (or maybe even 50 : 1).
One has been seen in Spain recently.
American Wigeon is a scarcer vagrant in Europe, but hybrids are seen in
small numbers. I don't have a ratio, but I would guess there is a higher
percentage of hybrid wigeon compared to pure American Wigeons than is the
case in Teal
(A male hybrid was in Norfolk recently)
cheers
Richard
sales(AT)birdingworld.co.uk
(Birding World, Books for Birders & Birdline)
Bird Information Service, Stonerunner, Coast Road,
Cley next the Sea, Holt, Norfolk, NR25 7RZ, UK
..................................
REF:
11 March 2002 01:28
Overall, I think the ration of Common Teal to hybrids is about 3:1 in the
Pac NW.
And my estimate for Eur Wigeon to hybrid wigeon is about 20:1.
Steven Mlodinow
----DELETED text/html MIME SECTION----
[ << | >> | ^^ ]
Subject: Re: female wigeon
From: "Norman D.van Swelm" <Norman.vanswelm(AT)WXS.NL>
Date: 26 Mar 2002 1:55pm
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----INCLUDING text/plain MIME SECTION----
=20
=20
Will Russell wrote:>I agree with David Sibley's comment that finding =
female Eurasian Wigeon can take some close study but it also occurs to =
me that the wigeon may do some of the job for us. Literature suggests =
that more than 80% of female wigeon are paired by March and assuming =
that these species mate assortively (i.e female Eurasian Wigeon prefer =
male Eurasian Wigeon, if available...perhaps a large asumption)<
=20
Not only would I not put my hand in the fire for the latter when you =
have seen duck-mating sorties it is unlikely the female duck knows who =
is the happy father! Although duck pair formation takes place in the =
winter quarters, my guess is some handsome Wigeons from Siberia met some =
galls in the West briefly in between flights and that this is how it all =
began. In the end the question is wether any of the Wigeon females you =
see out there with them are pure Eurasian!
Norman
----DELETED text/html MIME SECTION----
[ << | >> | ^^ ]
Subject: Re: Eurasian Wigeon numbers and hybrids
From: "Lethaby, Nick" <nlethaby(AT)TI.COM>
Date: 26 Mar 2002 2:02pm
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----
All:
Based on what I have seen on the west coast, I would agree that hybrid
Wigeon are fairly frequent and not that rare at all. Pure male Eurasian
Wigeon show just a very small patch of green around the eye that is only
visible at very close range such as in parks where the birds come to bread.
I suspect hybrids may be even more frequent. I remember an article (I think
in the HK bird report) where there was a bird that looked exactly like a
male American Wigeon but called like a Eurasian. If this was a result of
being a hybrid (as opposed to it leaning the wrong call), then it could be
very difficult to detect all hybrids visually.
My impression is that all three of the common Eurasian duck visitors to NA -
E. Wigeon, E. Teal, and Tufted Duck - are hybridizing fairly frequently with
NA species. There's been some controversy over 'short-tufted' Tufted Ducks
on the west coast in the past.
Nick Lethaby
-----Original Message-----
From: David Beaudette [mailto:drtbrdr(AT)EARTHLINK.NET]
Sent: Tuesday, March 26, 2002 11:42 AM
To: BIRDWG01(AT)listserv.arizona.edu
Subject: Re: [BIRDWG01] Eurasian Wigeon numbers and hybrids
Dear ID Birders,
I was curious about Wayne Webers remark that "I would caution all observers
to be careful in identifying supposed
hybrids. Pure Eurasian Wigeon CAN sometimes show some green on the sides of
the head where male Americans have a green patch."
My question is: How do we know that a Eurasian Wigeon with green on the
sides of the head is a pure Eurasian?
Good Birding,
Dave Beaudette
Wenatchee, WA
drtbrdr(AT)earthlink.net
-----Original Message-----
From: Wayne C. Weber <contopus(AT)SHAW.CA>
To: BIRDWG01(AT)listserv.arizona.edu <BIRDWG01(AT)listserv.arizona.edu>
Date: Tuesday, March 26, 2002 9:56 AM
Subject: Re: [BIRDWG01] Eurasian Wigeon numbers and hybrids
Bird ID People,
I am astounded by the remarks of Steve Mlodinow, who reports seeing 5
hybrid male AMERICAN x EURASIAN WIGEON in a flock of 2000 wigeon on
the Samish Flats, WA; Jon King, who reports seeing 6 hybrid male
wigeon among only about 650 wigeon at Delta, BC; and especially those
of David Sibley, who reports seeing "about 2 hybrids for every 3 pure
males" at Bolinas Lagoon, CA.
I have studied birds (including wigeon) intensively for 35 years in
the Pacific Northwest, mainly in the Vancouver, BC area and in
northwestern Washington. In that time, I have scanned wigeon flocks
hundreds of times looking for EURASIAN WIGEON and hybrids. I have
never seen more than one hybrid male wigeon at once, although I have
seen more than 40 pure Eurasians in a flock several times.
Until recently, hybrid wigeon were considered to be one of the rarest
dabbling duck hybrids in North America. In 1974, I found and carefully
described a hybrid wigeon that I discovered on the Vancouver, BC
Christmas Bird Count. At that time, to the best of my knowledge, only
two such hybrids had ever been reported previously in North America.
Despite my careful notes, the CBC Regional Editor at the time
questioned the identification and refused to publish the record!!
I would caution all observers to be careful in identifying supposed
hybrids. Pure Eurasian Wigeon CAN sometimes show some green on the
sides of the head where male Americans have a green patch. An
identification as a hybrid should be based on several characters
(colour of head overall, colour of crown, colour of back, colour of
flanks. call-note), and not just on whether there is some green on the
sides of the head.
At the same time, I clearly need to put more effort into identifying
female Eurasian Wigeon. I have identified rufous-morph females on a
number of occasions, but I have subscribed to the once-widespread
philosophy that gray-morph females were not safely identifiable in the
field. Clearly, some gray-morph females can be safely identified, bit
it seems that others cannot, at least at the distances and under the
conditions in which we usually see them.
As for numbers of Eurasians, there has been a steady and impressive
increase in the numbers in the Pacific Northwest since I first began
birding the Vancouver area in the late 1960s. This increase was well
documented by Mike Edgell in a paper in the Journal of Biogeography
(Vol. 11, pages 27-39, 1984), and has continued unabated since that
time. However, Jon King's count of 40 male Eurasians and 16 females
among 590 American Wigeon at Delta, BC in Nov. 2001 is exceptional. I
bird this area frequently, and a ratio of 1 or 2 male Eurasians per
100 Americans (or 2 to 4% of the total number of wigeon, assuming that
the sex ratio is about equal) is more typical.
Clearly, we all need to be more careful in identifying female Eurasian
Wigeon and in identifying supposed hybrid males. I have seen nothing
yet to convince me that American x Eurasian Wigeon is anything other
than a very rare hybrid in North America. As I mentioned in a message
to this group on March 19th, I have observed hybrid EURASIAN x
AMERICAN GREEN-WINGED TEAL in the Vancouver area far more often than
hybrid wigeon (and have several times seen 2 or 3 hybrid teal in the
same flock), even though the pure Eurasian form (COMMON TEAL, if you
prefer) is much scarcer than EURASIAN WIGEON.
Wayne C. Weber
Kamloops and Delta, BC
contopus(AT)shaw.ca
(Vancouver, BC CBC compiler, 1973-1994)
----- Original Message -----
From: David Sibley <dsibley(AT)SHORE.NET>
To: <BIRDWG01(AT)listserv.arizona.edu>
Sent: Monday, March 25, 2002 11:48 AM
Subject: Re: [BIRDWG01] Eurasian Wigeon numbers
Hi All,
It is impossible to state any ratio of female to male Eurasian Wigeon
without doing some SERIOUS looking. I think it's safe to say that none
of us
has ever looked carefully enough, at enough wigeon, to make any
comments
about the real sex ratio. Just because we haven't picked out as many
females doesn't mean they aren't there. This question might be
resolved by someone taking the time to look at relatively small groups
of wigeon (100 might be manageable) at very close range, and checking
each and every individual. At a park in Victoria, BC last fall I
looked at about 50 wigeon at distances ranging from 10 to 30 feet.
There were no male Eurasians but I picked out one female Eurasian
quickly, and 5 minutes later a second one. Around Bolinas, California
ten years ago I found about half as many female as male Eurasians, and
my sense was that I was just missing the females because many wigeon
were just too far away to check. I would be willing to bet that given
a thorough and objective study one would find equal numbers of males
and females.
I am also intrigued by the discussion of hybrids, since male hybrids
are
generally pretty obvious. My experience in eastern North America is
that
there are very few records of hybrids. I've seen one, and heard of a
few
others. On the other hand, California supports a high percentage of
hybrids
in winter, and I've seen hybrids at many other places along the west
coast
from Southern California to Alaska. My experience ten years ago(I'll
have to
be a bit vague now) was that at Bolinas Lagoon there were about 2
hybrids
for every 3 pure males -- nearly equal numbers, the pure birds just
slightly
more numerous. This is in contrast to the situation in eastern North
America, and now, it would seem, in contrast to the situation in BC.
Is this
a case of the BC hybrids being overlooked? or a real difference in the
winter range of hybrids?
David Sibley
Concord, MA
----DELETED text/html MIME SECTION----
[ << | >> | ^^ ]
Subject: Re: Eurasian Wigeon numbers and hybrids
From: Peter Adriaens <peter.adriaens(AT)dutchbirding.nl>
Date: 26 Mar 2002 2:17pm
Hi,
> Pure male Eurasian
> Wigeon show just a very small patch of green around the eye that is
> only visible at very close range such as in parks where the birds come
> to bread.
>
In the large flocks of Eurasian Wigeons that we get over here on the
Western European continent in winter, males with a rather extensive and
obvious greenish patch around the eye are not that exceptional. In such
birds, the patch may curve down slightly towards the rear head, and may be
rather pointed at the end. In all other respects, including the colour of
the axillaries, they are always entirely typical Eurasian Wigeon.
Regards,
Peter Adriaens
BELGIUM
[ << | >> | ^^ ]
Subject: Black vs. Gray-bellied Brant
From: pabuckley <pabuckley(AT)URI.EDU>
Date: 26 Mar 2002 3:16pm
----INCLUDING text/plain MIME SECTION----
On 14 March 2002, at Long Island, NY's Jacob Riis Park on the
Rockaways barrier beach separating Jamaica Bay from the Atlantic
Ocean, PAB and SSM found an odd Black Brant in a flock of 500 or so
Atlantic or Pale-bellied Brant, Branta bernicla hrota. One week
previous, SSM had found another off-color Black Brant some 20 miles
east at Jones Inlet, but efforts to relocate it had been
unsuccessful. Both seemed to differ from typical Black Brant, B. b.
nigricans, in showing rather obvious contrast between their black
neck stockings and their brown backs and aprons. The Riis Park bird
in particular showed similar dorsal coloration to accompanying hrota
and further differed from typical nigricans by virtue of its
extensive rectangular (vs. wedge-shaped) white flank patch and its
more restricted dark apron, which extended only slightly beyond the
legs and faded (lightened) noticeably rearward.
In view of these unexpected characters, we wonder if one or both
might not be GRAY-BELLIED BRANT-a name first used by Canadian
Wildlife Service biologists and now widely applied to a little-known
population breeding in the western Canadian Arctic, wintering mostly
in Puget Sound, WA, but proven to have occurred as far afield as Baja
California and the British Isles. Neither individual was able to be
photographed when found, but on 16 March 2002, SSM and others
relocated and photographed both. They may be viewed at
<http://www.geocities.com/gsbas2000> where you may choose between
faster-loading, lower resolution, or slower-loading, higher
resolution versions.
We are most curious to know if observers anywhere see similar birds,
either regularly or occasionally. We are even more interested in how
such individuals would be regarded, and whether observers consider
such plumages to be within the normal range of variation for Black
Brant; examples of extreme Black Brant plumages; or beyond the
expected/known plumage limits for that taxon.
Private or FRONTIERS comments will be equally welcomed, appreciated,
and acknowledged.
P.A. Buckley <pabuckley(AT)uri.edu>
S.S. Mitra <ShaiMitra(AT)aol.com>
----DELETED text/html MIME SECTION----
[ << | >> | ^^ ]
Subject: Re: Eurasian Wigeon numbers and hybrids
From: Michael Dossett <phainopepla(AT)YAHOO.COM>
Date: 26 Mar 2002 5:00pm
Hello,
Dave, you bring up an interesting point. Green in the
face of a Eurasian Wigeon often makes me suspicious of
the bird I am looking at. Unless there is more than
just a small green patch, however, I am generally
inclined to write it off as a pure Eurasian (although
this may make it hard to detect various backcrosses).
Do my criteria for picking out hybrids this way seem
reasonable?
It is my experience that most of the Eurasian x
American Wigeon hybrids I have found tend to show more
than just a small green patch around the face. These
birds tend to be fairly obvious in that a bird with
extensive amounts of green in the face will almost
invariably also have some white in the face as well
(especially around the forehead, but also the cheeks),
and often there is quite a bit. Body color in these
birds often has feathers of both colors present and
rarely is just gray as in a typical Eurasian. Have
others found this to be the case?
In any case I have to disagree with Wayne and say that
he may be underestimating how many hybrid wigeon there
are around. I have seen multiple hybrids in a flock
on a number of occaisions, generally more often the
case in flocks that are migrants rather than those
which winter in this area. At Greenlake in Seattle,
there is invariably atleast one and usually two or
three male Eurasian Wigeon in the wintering flock. I
would estimate probably around 200 Americans in this
flock during most years. I have once encountered an
obvious hybrid male that wintered over and several
times seen flocks in March with 1 or 2 hybrids which
had not been there in previous weeks and are not there
the following week. The same happens in September and
October as well. I have noticed this pattern with a
few other flocks, and can say that even with the
criteria that I consider to be fairly conservative in
distinguishing hybrid males.
For what it is worth, my impression of migrant flocks
is that the ratio of hybrids to pure Eurasians of 1:10
is not terribly unusual.
Michael Dossett
Seattle, Washington
phainopepla(AT)yahoo.com
--- David Beaudette <drtbrdr(AT)EARTHLINK.NET> wrote:
> Dear ID Birders,
> I was curious about Wayne Webers remark that "I
> would caution all observers
> to be careful in identifying supposed
> hybrids. Pure Eurasian Wigeon CAN sometimes show
> some green on the sides of
> the head where male Americans have a green patch."
> My question is: How do we know that a Eurasian
> Wigeon with green on the
> sides of the head is a pure Eurasian?
>
> Good Birding,
> Dave Beaudette
> Wenatchee, WA
> drtbrdr(AT)earthlink.net
> -----Original Message-----
> From: Wayne C. Weber <contopus(AT)SHAW.CA>
> To: BIRDWG01(AT)listserv.arizona.edu
> <BIRDWG01(AT)listserv.arizona.edu>
> Date: Tuesday, March 26, 2002 9:56 AM
> Subject: Re: [BIRDWG01] Eurasian Wigeon numbers and
> hybrids
>
>
> Bird ID People,
>
> I am astounded by the remarks of Steve Mlodinow, who
> reports seeing 5
> hybrid male AMERICAN x EURASIAN WIGEON in a flock of
> 2000 wigeon on
> the Samish Flats, WA; Jon King, who reports seeing 6
> hybrid male
> wigeon among only about 650 wigeon at Delta, BC; and
> especially those
> of David Sibley, who reports seeing "about 2 hybrids
> for every 3 pure
> males" at Bolinas Lagoon, CA.
>
> I have studied birds (including wigeon) intensively
> for 35 years in
> the Pacific Northwest, mainly in the Vancouver, BC
> area and in
> northwestern Washington. In that time, I have
> scanned wigeon flocks
> hundreds of times looking for EURASIAN WIGEON and
> hybrids. I have
> never seen more than one hybrid male wigeon at once,
> although I have
> seen more than 40 pure Eurasians in a flock several
> times.
>
> Until recently, hybrid wigeon were considered to be
> one of the rarest
> dabbling duck hybrids in North America. In 1974, I
> found and carefully
> described a hybrid wigeon that I discovered on the
> Vancouver, BC
> Christmas Bird Count. At that time, to the best of
> my knowledge, only
> two such hybrids had ever been reported previously
> in North America.
> Despite my careful notes, the CBC Regional Editor at
> the time
> questioned the identification and refused to publish
> the record!!
>
> I would caution all observers to be careful in
> identifying supposed
> hybrids. Pure Eurasian Wigeon CAN sometimes show
> some green on the
> sides of the head where male Americans have a green
> patch. An
> identification as a hybrid should be based on
> several characters
> (colour of head overall, colour of crown, colour of
> back, colour of
> flanks. call-note), and not just on whether there is
> some green on the
> sides of the head.
>
> At the same time, I clearly need to put more effort
> into identifying
> female Eurasian Wigeon. I have identified
> rufous-morph females on a
> number of occasions, but I have subscribed to the
> once-widespread
> philosophy that gray-morph females were not safely
> identifiable in the
> field. Clearly, some gray-morph females can be
> safely identified, bit
> it seems that others cannot, at least at the
> distances and under the
> conditions in which we usually see them.
>
> As for numbers of Eurasians, there has been a steady
> and impressive
> increase in the numbers in the Pacific Northwest
> since I first began
> birding the Vancouver area in the late 1960s. This
> increase was well
> documented by Mike Edgell in a paper in the Journal
> of Biogeography
> (Vol. 11, pages 27-39, 1984), and has continued
> unabated since that
> time. However, Jon King's count of 40 male Eurasians
> and 16 females
> among 590 American Wigeon at Delta, BC in Nov. 2001
> is exceptional. I
> bird this area frequently, and a ratio of 1 or 2
> male Eurasians per
> 100 Americans (or 2 to 4% of the total number of
> wigeon, assuming that
> the sex ratio is about equal) is more typical.
>
> Clearly, we all need to be more careful in
> identifying female Eurasian
> Wigeon and in identifying supposed hybrid males. I
> have seen nothing
> yet to convince me that American x Eurasian Wigeon
> is anything other
> than a very rare hybrid in North America. As I
> mentioned in a message
> to this group on March 19th, I have observed hybrid
> EURASIAN x
> AMERICAN GREEN-WINGED TEAL in the Vancouver area far
> more often than
> hybrid wigeon (and have several times seen 2 or 3
> hybrid teal in the
> same flock), even though the pure Eurasian form
> (COMMON TEAL, if you
> prefer) is much scarcer than EURASIAN WIGEON.
>
> Wayne C. Weber
> Kamloops and Delta, BC
> contopus(AT)shaw.ca
> (Vancouver, BC CBC compiler, 1973-1994)
>
>
> ----- Original Message -----
> From: David Sibley <dsibley(AT)SHORE.NET>
> To: <BIRDWG01(AT)listserv.arizona.edu>
> Sent: Monday, March 25, 2002 11:48 AM
> Subject: Re: [BIRDWG01] Eurasian Wigeon numbers
>
>
> Hi All,
>
> It is impossible to state any ratio of female to
> male Eurasian Wigeon
> without doing some SERIOUS looking. I think it's
> safe to say that none
> of us
> has ever looked carefully enough, at enough wigeon,
> to make any
> comments
> about the real sex ratio. Just because we haven't
> picked out as many
> females doesn't mean they aren't there. This
> question might be
> resolved by someone taking the time to look at
> relatively small groups
> of wigeon (100 might be manageable) at very close
> range, and checking
> each and every individual. At a park in Victoria, BC
> last fall I
> looked at about 50 wigeon at distances ranging from
> 10 to 30 feet.
> There were no male Eurasians but I picked out one
> female Eurasian
> quickly, and 5 minutes later a second one. Around
> Bolinas, California
> ten years ago I found about half as many female as
> male Eurasians, and
> my sense was that I was just missing the females
> because many wigeon
> were just too far away to check. I would be willing
> to bet that given
> a thorough and objective study one would find equal
> numbers of males
> and females.
>
> I am also intrigued by the discussion of hybrids,
> since male hybrids
> are
> generally pretty obvious. My experience in eastern
> North America is
> that
> there are very few records of hybrids. I've seen
> one, and heard of a
> few
> others. On the other hand, California supports a
> high percentage of
> hybrids
> in winter, and I've seen hybrids at many other
> places along the west
> coast
> from Southern California to Alaska. My experience
> ten years ago(I'll
> have to
> be a bit vague now) was that at Bolinas Lagoon there
> were about 2
>
=== message truncated ===
__________________________________________________
Do You Yahoo!?
Yahoo! Movies - coverage of the 74th Academy Awards®
http://movies.yahoo.com/
[ << | >> | ^^ ]
Subject: Re: Eurasian Wigeon numbers
From: Jon King <king(AT)PRBO.ORG>
Date: 26 Mar 2002 8:44pm
Dear IDFrontiers,
Sibley appears to have misinterpreted my comments, or perhaps I was
insufficiently clear. In my own studies of wigeon throughout BC to Baja
I have typically found AT LEAST one female Eurasian Wigeon to every 2-4
males. I was not attempting to provide a definitive ratio. This is a
provisional estimate based on a lot of serious looking, and suggests a
much higher frequency of females than seems to be generally reported.
However, as I also stated, the available evidence suggests that female
EUWIs are being widely missed, and I am sure that I miss plenty myself.
Thus I would agree that a ratio closer to one to one might be expected
(although perhaps varying with season and location).
Sibley is correct in suggesting that identification of male hybrids are
generally fairly straightforward. I suspect their frequency may be
increasing, even irrespective of advances in ID knowledge, at least in
some areas nearer the fringe of the main wintering range. I was
fortunate to live in Bolinas for three winters in the late 1990s and to
study wigeon on the lagoon almost daily; the ratio of male EUWIs to
hybrids then was one-to-one, a slight increase from 3:2 that Sibley had
several years before. As with females, hybrids are doubtless overlooked,
and the problem is exacerbated by them often being simply considered
oddities and so not being reported even when they are seen.
Cheers, Jon.
> ----- Original Message -----
> From: David Sibley <dsibley(AT)SHORE.NET>
> To: <BIRDWG01(AT)listserv.arizona.edu>
> Sent: Monday, March 25, 2002 11:48 AM
> Subject: Re: [BIRDWG01] Eurasian Wigeon numbers
>
> Hi All,
>
> It is impossible to state any ratio of female to male Eurasian Wigeon
> without doing some SERIOUS looking. I think it's safe to say that none
> of us
> has ever looked carefully enough, at enough wigeon, to make any
> comments
> about the real sex ratio. Just because we haven't picked out as many
> females doesn't mean they aren't there. This question might be
> resolved by someone taking the time to look at relatively small groups
> of wigeon (100 might be manageable) at very close range, and checking
> each and every individual. At a park in Victoria, BC last fall I
> looked at about 50 wigeon at distances ranging from 10 to 30 feet.
> There were no male Eurasians but I picked out one female Eurasian
> quickly, and 5 minutes later a second one. Around Bolinas, California
> ten years ago I found about half as many female as male Eurasians, and
> my sense was that I was just missing the females because many wigeon
> were just too far away to check. I would be willing to bet that given
> a thorough and objective study one would find equal numbers of males
> and females.
>
> I am also intrigued by the discussion of hybrids, since male hybrids
> are
> generally pretty obvious. My experience in eastern North America is
> that
> there are very few records of hybrids. I've seen one, and heard of a
> few
> others. On the other hand, California supports a high percentage of
> hybrids
> in winter, and I've seen hybrids at many other places along the west
> coast
> from Southern California to Alaska. My experience ten years ago(I'll
> have to
> be a bit vague now) was that at Bolinas Lagoon there were about 2
> hybrids
> for every 3 pure males -- nearly equal numbers, the pure birds just
> slightly
> more numerous. This is in contrast to the situation in eastern North
> America, and now, it would seem, in contrast to the situation in BC.
> Is this
> a case of the BC hybrids being overlooked? or a real difference in the
> winter range of hybrids?
>
> David Sibley
> Concord, MA
--
-----------------------------------------------------
Jon R. King
Research Associate, Point Reyes Bird Observatory.
Home office: 2707 D Street, Sacramento, CA 95816, USA
Tel/fax: (916) 448 5945 E-mail: king(AT)prbo.org
-----------------------------------------------------
[ << | >> | ^^ ]
Subject: Re: FW: Hybrids Green-winged x
Eurasian teals (A.carolinensis x crecca)
From: Millington/BIS <sales(AT)birdingworld.co.uk>
Date: 27 Mar 2002 3:46am
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Hi Colin and all
Although I broadly agree with Colin Bradshaw's sentiments, I must =
counter his assumptions.
=20
It is pointless to guess that hybrids are not being identified or that =
nobody is looking. The former is pure speculation, the latter is =
invalid, since my figures only relate to identified birds (therefore =
found by people looking at Teals).
=20
For the sake of accuracy, we must content ourselves with just the facts =
(i.e identified birds).
The number of male Green-winged Teals in Britain could well be double my =
figure, whereas my figure of ''less than three a year'' for hybrids =
reported in the whole of Europe is a vast overstatement; it is in fact =
closer to one every three years.
=20
This puts the ratio of identified male hybrids to pure male Green-winged =
Teals in Europe closer to 1 in 250 or 500, ten times fewer than my =
ludicrously conservative figure of 1 in 25 or 50 ......
=20
Currently, hybrid teal sightings really are truly exceptional here =
(sorry, Colin, teal identifiable as, or identified as, hybrids).=20
=20
cheers
Richard
=20
sales(AT)birdingworld.co.uk
Stonerunner, Coast Road,
Cley next the Sea, Holt, Norfolk, NR25 7RZ, UK
Website www.birdingworld.co.uk
-----Original Message-----
From: Colin Bradshaw <drcolin.bradshaw(AT)BTINTERNET.COM>
To: BIRDWG01(AT)listserv.arizona.edu <BIRDWG01(AT)listserv.arizona.edu>
Date: 26 March 2002 20:52
Subject: [BIRDWG01] FW: [BIRDWG01] Hybrids Green-winged x Eurasian =
teals (A.carolinensis x crecca)
=20
=20
=20
-----Original Message-----
From: Colin Bradshaw [mailto:drcolin.bradshaw(AT)btinternet.com]
Sent: 26 March 2002 20:34 PM
To: Millington/BIS
Subject: RE: [BIRDWG01] Hybrids Green-winged x Eurasian teals =
(A.carolinensis x crecca)
=20
=20
I think you need to be wary of these figures as, of course, it may =
be that people are less adept at identifying hybrid GW x European Teal =
than they are Am W x EW hybrids. This could be for two reasons. The =
first is that there are more distinct differences between the two =
species of Wigeon whilst the flank/head pattern differences of the Teal =
is relatively subtle.
=20
More likely is the fact that, in the UK, many people seem to =
scrutinise Wigeon flock looking for 'Yanks' but I've seen few people do =
the same for Teal flocks
=20
Colin Bradshaw
----DELETED text/html MIME SECTION----
[ << | >> | ^^ ]
Subject: Re: Hybrids Green-winged x Eurasian teals
From: Laurent Raty <l_raty(AT)HOTMAIL.COM>
Date: 27 Mar 2002 4:45am
Hi,
Just a thought: we tend to assume that birds showing a hybrid phenotype are,
indeed, F1 crecca x carolinensis, but was it actually shown to be the case?
As Allen pointed out earlier, when we were talking about gulls, F1 hybrids
are not always intermediate - they can be very similar to one of their
parents. For instance, if we assume that crecca phenotype is dominant in F1,
a F1 becomes impossible to detect. Backcrossing this bird with a crecca will
most probably produce a crecca-like descendance too, that will go unnoticed
as well. It could then be that the phenotype we call "hybrid" arises in fact
only in F2s, issued from backcrossing a crecca-like F1 with a pure
carolinensis, or from crossing two F1 hybrids.
That such birds would be exceptional in Europe were carolinensis is a
vagrant, but much more frequent in N America, would not be a surprise...
Laurent
Laurent Raty
l_raty(AT)hotmail.com
Brussels, Belgium
[ << | >> | ^^ ]
Subject: Jack Snipe {Lymnocryptes minimus} age help
From: Bill Elrick <belrick(AT)OPTONLINE.NET>
Date: 27 Mar 2002 7:05am
Hi,
I just returned from a trip to the UK and helped some fellow ringers catch
Jack Snipe {Lymnocryptes minimus}, they seemed to be unsure of the age
designations. Would someone like to take a look and say what they think this
birds age may be.
I noticed a marked difference in tertials and the alula.
The photos can be found at
http://photos.groups.yahoo.com/group/oldearth/lst?.dir=/Bird+Photos/Jack+Sni
pe&.src=gr&.order=&.view=t&.done=http%3a//photos.groups.yahoo.com/group/olde
arth/lst%3f.dir=/Bird%2bPhotos%26.src=gr%26.view=t
I have set the properties of the image to medium, so they are large files. I
think you can view the photos without joining the group.
Bill Elrick
NJ, USA
[ << | >> | ^^ ]
Subject: Wigeon again
From: will russell <russellbw(AT)EARTHLINK.NET>
Date: 27 Mar 2002 8:24am
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----INCLUDING text/plain MIME SECTION----
There are currently two parallel and only partly overlapping discussions =
underway with regards to wigeon; the detectability of female Eurasian =
Wigeon and the frequency of Eurasian x American Wigeon hybrids.
My earlier comment intended as a contribution to the first of these two =
discussions was viewed in some quarters as a part of the second.
The free-for-alls referred to by van Swelm are part of the "courtship" =
of most (all?) dabbling ducks and take place prior to pair formation. =
Once the female has chosen a male, those activities largely cease and =
the pair can be seen in very close association with the male usually =
just behind the female wherever she goes. There is no indication that =
these bonds, once formed, are overly fragile.=20
If by late March most female wigeon have in fact chosen mates, it would =
be interesting for birders in the Pacific Northwest to look closely at =
the females currently associating with male Eurasians. If the species =
mate assortively and if there are a reasonable number of (perhaps =
undetected) female Eurasians among the wigeon population, a substantial =
percentage of the birds presently associating with male Eurasians should =
be female Eurasians. Bear in mind that there is unlikely to be one =
female Eurasian for every male Eurasian, unless all the birds are =
one-year olds, as sex ratios of adults are skewed in favor of males due =
to higher mortality in females. If of course, most of the male =
Eurasians are consorting with female Americans, the case for numerous =
hybrids in the wintering population seems strengthened.
I brushed up on wigeon behavior by consulting the Birds of North America =
(BNA) contribution on American Wigeon (Thomas Mowbray No. 401 1999).
Will Russell
russellbw(AT)earthlink.net
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[ << | >> | ^^ ]
Subject: GRAY-BELLIED BRANT
From: "Wayne C. Weber" <contopus(AT)SHAW.CA>
Date: 27 Mar 2002 9:34am
Bird ID People,
P.A. Buckley's note about a probable GRAY-BELLIED BRANT at Long
Island, NY prompts me to forward the attached note from Dr. Fred
Cooke-- recently retired from Simon Fraser University in Burnaby, BC.
The note was originally sent to TWEETERS, the Washington State E-mail
group, in February 2000. It addresses the taxonomic and conservation
status of this form, which has still not been described as a separate
subspecies. Dr. Cooke is a world authority on Arctic-nesting geese,
and incoming President of the American Ornithologists' Union.
Gray-bellied Brant are rarely seen in winter away from the Pacific
Coast of North America. However, a Brant of this form appeared last
fall from November 6 to 12 at Kamloops BC, and was closely observed by
me and several other observers. Brant of any form are extremely rare
around Kamloops (which is about 250 km inland), and there are only 3
previous records of any form of Brant in the area.
I have not yet had a chance to look at the photos of the Long Island
bird, so can't comment on its identification. However, like Buckley, I
am curious to know how many records of this form there are on the east
coast or inland in North America.
Wayne C. Weber
Kamloops and Delta, BC
contopus(AT)shaw.ca
> >
> > ---------- Forwarded message ----------
> > Date: Mon, 21 Feb 2000 10:54:01 -0800
> > From: Fred Cooke <fcooke(AT)sfu.ca>
> >
> > I'd like to alert Tweeters to the issue of Gray-bellied
> > Brant. Many of you will know them as the wintering
> > population of Brant that occurs at Padilla Bay. Scientific work
> > since 1990 has shown them to be distinctly different
> > genetically from the Black Brant (Branta bernicla
> > nigricans) which also winters in the Pacific Northwest.
> > Most recent scientific evidence shows that the Gray-bellied
> > race is one of 4 populations currently classified as Branta
> > bernicla hrota, (the same subspecific name as the Atlantic
> > Brant), but I'm sure it will soon be given sub-specific (or
> > even full species) status. The most IMPORTANT feature is
> > that this is one of the RAREST populations of geese in the
> > world. The world population is probably less than 7000
> > birds. It breeds in the Perry Islands in the North-west
> > corner of Arctic Canada, and almost the whole world
> > population winters in Skagit County Washington and now
> > increasingly in the Lower Mainland of BC. This population is
> > still hunted despite its rarity, and in fact hunting
> > practice in Washington favours the killing of this
> > sub-species rather than the commoner B.b.nigricans) which
> > has a world population of around 130,000.
> >
> > This has become a conservation issue for some of us in BC
> > because in recent years Brant have increased as a winter
> > visitor in increasing numbers, with as many as 1000 birds
> > seen in Boundary Bay and Roberts Bank. MORE IMPORTANTLY, up
> > to 20% of the sightings of Brant are Gray-bellied (B.b.
> > hrota). I hope birders can start looking out for both
> > subspecies and recording them. Gray-bellies are usually
> > clearly gray bellied and have a distinct demarcation between
> > black chest and gray belly.
> >
> > My own view is that in view of the rarity of this
> > population, we should be encouraging State and Federal
> > Agencies, to
> > a) manage these two subspecies separately, and
> > b) to take measure to ban or more severely restrict hunting
> > on the rarer subspecies.
> >
> > Fred Cooke
> > Simon Fraser Univ.
> > fcooke(AT)sfu.ca
> >
>(current E-mail address: f.cooke(AT)uea.ac.uk )
[ << | >> | ^^ ]
Subject: Hybrid teals and wigeon
From: =?iso-8859-1?Q?Ricard_Guti=E9rrez?= <GUTARB(AT)TERRA.ES>
Date: 27 Mar 2002 10:46am
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----INCLUDING text/plain MIME SECTION----
Hi All
With regards to the situation in Spain, we at the Spanish Rarities
Committee have received so far 24 records of carolinensis of which 8 are
still under study and at least involve two claimed 'hybrid-looking' birds
which are those featured in one special page in my website
www.rarebirdspain.net . Giving all 24 records are good, we should have here
a ratio 2 hybrids/ 22 pure carolinensis.But again this could be a matter of
(recent) luck because I agree these hybrid birds here are (or have been)
very rare up to now.
The total overwintering population in Catalonia, NE Spain is c.11000-18000
birds [1999-2001]. Of those, no less than 4000 (over one third of
overwintering population on average) are scanned one by one in search of
possible carolinensis. This is done at least since the mid-eighties. No
results were obtained until march 2002, when the previously mentioned two
birds, one pure male and one putative hybrid, were found. Moreover, these
birds were not overwintering individuals but 'returning' to the breeding
grounds birds, moving North. However, they have remained in the place where
they were seen for almost a month (still there).
Anyway, what I'd like to point out is that at least in the Mediterranean
NE corner of Spain, this species (and the hybrids too) is very rare compared
with other vagrants (e.g Sociable plover, of which we've seen one this
monday -see the photos at the above website- is almost annual in the NE)
Regarding the Wigeon hybrids, we had some time ago a penelope which had
some green in its face but that otherwise was normal and that caused us some
trouble. Advice from people from AERC solved the issue. The photos of this
bird are still at:
http://www.gencat.es/mediamb/rndelta/graf/idllob12.jpg
http://www.gencat.es/mediamb/rndelta/graf/idllob13.jpg
Ricard Gutiérrez
CR/SEO
www.rarebirdspain.net
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[ << | >> | ^^ ]
Subject: wigeon plumage changes
From: Paul Lehman <lehmfinn(AT)BELLATLANTIC.NET>
Date: 27 Mar 2002 2:41pm
IDFrontiers:
An interesting situation with wigeon plumages is that sometimes they
evolve from "hybrid" to "pure" bird as the bird molts. At least that has
been the situation with a returning male to the Cape May, NJ, area. This
bird has been returning annually to the same ponds every fall since
1993, often arriving by mid-September, and often staying well into
November and sometimes the entire winter. When it arrives it is in
eclipse plumage, and at that time it has a dull rusty-buff-brown head
with an extensive greenish (or at least dusky-green) patch through the
eye, to the extent that many visiting good birders who see it at this
time call it a hybrid. But as the bird gains "breeding" plumage over the
following month to six weeks, most of the green disappears and the fully
molted, bright red-headed bird then has a mere small "tick" of green
behind the eye, which all birders agree is well within the variation of
pure Eurasians. Nobody would ever call the molted bird a hybrid, as it
pooks "pure" in all regards.
Paul Lehman
[ << | >> | ^^ ]
Subject: Hybrid waterfowl threads
From: Angus Wilson <wilsoa02(AT)ENDEAVOR.MED.NYU.EDU>
Date: 27 Mar 2002 8:29pm
(1) Common Teal x Green-winged Teal hybrids
To add to the fascinating hybrid teal discussion, I've put some pictures
on 'Ocean Wanderers' of a suspected Common Teal x Green-winged Teal
hybrid, photographed recently near New York City, New York.
http://www.oceanwanderers.com/NYGWTealHyb.html
The photos aren't fabulous but may add a little to the debate. I welcome
any comments on the identity of this bird (preferably shared with
ID-Frontiers rather than private).
(2) Eurasian Wigeon x American Wigeon hybrids
Some photos of a puzzling wigeon that was discussed last year of
ID-Frontiers can be found at.
http://www.oceanwanderers.com/EurWig.html
Our initial thoughts were of a hybrid but but I'm not sure the issue was
fully resolved.
(3) Tufted Duck x scaup hybrids
http://www.oceanwanderers.com/Aythyahybrid.html
I wish to thank to Bruce MacTavish, Jennifer Hanson, Martin Reid, Ian
Paulsen, Alf Tore Mjös, Richard Millington, Peter Adriens, Tony
Leukering, Wayne Weber, Mary Beth Stowe and others for providing
comments on the _aythya_ hybrid. I must apologize for not getting back
to you directly but the last month has been very busy. At some point I
hope to add a summary of their extremely interesting comments on this
bird as well as useful suggestions of additional literature.
Steve Nanz has taken some more shots of this probable Tufted Duck x
scaup hybrid, showing the open wings, something I was unable to do.
http://homepage.mac.com/snanz/PhotoAlbum14.html#
There are some delightful photos on his web site.
Cheers,
Angus Wilson
New York City, USA
[ << | >> | ^^ ]
Subject: Re: Hybrid waterfowl threads
From: birddog <birddog(AT)SNET.NET>
Date: 27 Mar 2002 9:03pm
This winter, in Connecticut, we had a group of Green-winged-type Teal at a
small coastal pond that, for a short time, consisted of an adult male
Green-winged, an immaculate adult male Common, an apparent hybrid GW X
Common, a female paired up to the Common Teal, and an un-attached female (
so much for ratios). The hybrid looked somewhat like the New York bird in
that it showed a prominent but reduced horizontal white bar in the scapular
area but the bird showed a stonger vertical bar than the New York bird and
the yellowish area surrounding the green mask was very broad and distinct
along the bottom of the green facial patch but very indistinct to partially
missing on the upper half.
Mark Szantyr
----- Original Message -----
From: "Angus Wilson" <wilsoa02(AT)ENDEAVOR.MED.NYU.EDU>
To: <BIRDWG01(AT)listserv.arizona.edu>
Sent: Wednesday, March 27, 2002 6:56 PM
Subject: [BIRDWG01] Hybrid waterfowl threads
> (1) Common Teal x Green-winged Teal hybrids
>
> To add to the fascinating hybrid teal discussion, I've put some pictures
> on 'Ocean Wanderers' of a suspected Common Teal x Green-winged Teal
> hybrid, photographed recently near New York City, New York.
>
> http://www.oceanwanderers.com/NYGWTealHyb.html
>
> The photos aren't fabulous but may add a little to the debate. I welcome
> any comments on the identity of this bird (preferably shared with
> ID-Frontiers rather than private).
>
> (2) Eurasian Wigeon x American Wigeon hybrids
>
> Some photos of a puzzling wigeon that was discussed last year of
> ID-Frontiers can be found at.
>
> http://www.oceanwanderers.com/EurWig.html
>
> Our initial thoughts were of a hybrid but but I'm not sure the issue was
> fully resolved.
>
> (3) Tufted Duck x scaup hybrids
>
> http://www.oceanwanderers.com/Aythyahybrid.html
>
> I wish to thank to Bruce MacTavish, Jennifer Hanson, Martin Reid, Ian
> Paulsen, Alf Tore Mjös, Richard Millington, Peter Adriens, Tony
> Leukering, Wayne Weber, Mary Beth Stowe and others for providing
> comments on the _aythya_ hybrid. I must apologize for not getting back
> to you directly but the last month has been very busy. At some point I
> hope to add a summary of their extremely interesting comments on this
> bird as well as useful suggestions of additional literature.
>
> Steve Nanz has taken some more shots of this probable Tufted Duck x
> scaup hybrid, showing the open wings, something I was unable to do.
>
> http://homepage.mac.com/snanz/PhotoAlbum14.html#
>
> There are some delightful photos on his web site.
>
> Cheers,
>
> Angus Wilson
> New York City, USA
>
[ << | >> | ^^ ]
Subject: Teal variation
From: Martin Reid <upupa(AT)AIRMAIL.NET>
Date: 28 Mar 2002 7:30am
Dear Angus and all,
I've been wondering about the degree of normal variation in both forms of
teal, so I looked at a few samples on the Internet:
crecca:
http://www.md.ucl.ac.be/peca/test/Teal.jpg
http://www.junam.co.kr/jubird/JUNAM/IMAGE/winter%20bird/stoneori.jpg
http://www.inseparabile.com/_borders/a66.JPG
http://www.md.ucl.ac.be/peca/test/Teal2.jpg
http://digilander.iol.it/emstival/uccelli/alzavola.jpg
http://astro.ocis.temple.edu/~coguzt/cuneyt/atlaskus12.jpg
http://users.astronet.gr/dason/images/pulia/kirkiri.jpg
http://koti.mbnet.fi/malmip/lintukuvat/tavi.jpg
http://perso.club-internet.fr/fdesjard/especes/gd_lacs/sarcelle_hiver.JPG
carolinensis:
http://www.mbr-pwrc.usgs.gov/id/htmsl/h1390pi.jpg
http://www.mosquitonet.com/~jgilbert/Birds_ofinterior_alaska/images/gwte_pair_full.gif
- from this admittedly small sample, it looks as though the strength of the
facial lines is significantly variable on crecca, as is the presence, size
and shape of the light rear flank mark. What seems less variable is
"strength" or thickness of the upper flank vermiculations.
Thus I return to my earlier speculation about resumed hybrids, and how many
of them have any other features that are not found in a reasonable sample
of either pure taxon? I'm not suggesting that none of these are hybrids -
but are all of them hybrids? Might some be "pure" (in terms of immediate
lineage) creccas that, for some as-yet unknown reason, are expressing an
ancestral plumage trait - the vertical shoulder line - ?
I sure hope that Laurent Raty chimes in on this, as he has a way of
explaining the complexities of taxonomy/genetics in a way that I can
understand!
Regards,
Martin
Martin Reid
Fort Worth, Texas
upupa(AT)airmail.net
http://www.martinreid.com
[ << | >> | ^^ ]
Subject: Re: Teal variation
From: "Alain FOSSE (Angers, 49, France)" <alfosse(AT)bigfoot.com>
Date: 28 Mar 2002 9:23am
-----Message d'origine-----
De : Martin Reid <upupa(AT)AIRMAIL.NET>
À : BIRDWG01(AT)listserv.arizona.edu <BIRDWG01(AT)listserv.arizona.edu>
Date : jeudi, mars 28, 2002 15:36
Objet : [BIRDWG01] Teal variation
>Dear Angus and all,
>I've been wondering about the degree of normal variation in both forms of
>teal, so I looked at a few samples on the Internet:
>crecca:
+ http://membres.lycos.fr/digimages/sarhiv/sarhiv.htm
Best regards.
PS : no file attached, trash if there is one...
Alain Fosse
1, allee Alexandra-David-Neel, 49460 Montreuil-Juigne
47:31:35:N 00:35:42W
alfosse(AT)bigfoot.com alfosse(AT)wanadoo.fr alfosse(AT)chu-angers.fr
My digiscoping http://digimages.multimania.com/
My French list of the birds of the world
http://listoiseauxmonde.multimania.com/
Web site LPO Anjou http://www.lpo-anjou.org/
[ << | >> | ^^ ]
Subject: Re: Mystery Gull
From: "Robert H. Lewis" <lewis(AT)BWAY.NET>
Date: 28 Mar 2002 10:44am
> View the link below to see images of the 1st winter Mystery Gull
>
> http://photos.yahoo.com/c7echoes
>
> - leucistic "American" Herring Gull;
> - a very oddly patterned Thayer's Gull (redundant ?!?);
> - "American" Herring X ???? - Glaucous was originally proposed,
> - "Vega" Herring X Slaty-backed (pure conjecture, but no other
Dear Larofiles,
I'm coming in on this discussion late. For what it's worth, to me it
could well be just a pale smithsoniananus Herring. After that, maybe
Herring X Thayer's. I can't see the tail. West coast observers will have
to comment on the Herring X GLWG possibility.
Over the year's I've seen lots of oddly pale Herrings (smithsonianus) in
the spring, starting in mid February. For what it's worth, look at:
http://www.bway.net/~lewis/birds/comins/comin.html
http://www.bway.net/~lewis/birds/Thayers/thayers.html
http://www.bway.net/~lewis/birds/PaleHerrs/paleherrs.html
Bob Lewis
Sleepy Hollow NY
http://www.bway.net/~lewis/birds/gulls.html
[ << | >> | ^^ ]
Subject: Re: Teal variation
From: Peter Adriaens <peter.adriaens(AT)dutchbirding.nl>
Date: 28 Mar 2002 10:48am
Hello,
I don't think it has come up yet, but there is one more feature that is
useful when identifying male teals in breeding plumage, namely the pattern
of the tertials.
Perhaps most people know this already, but in male Common (Eurasian) Teal
the grey tertials normally have a rather obvious blackish shade along the
dark shafts, which is easily seen in the field. In male Green-winged Teal,
the tertials look mostly uniformly grey. In the hand, it can be easily seen
that the shafts are actually black (see for example
http://www.npwrc.usgs.gov/resource/tools/duckplum/gwteal.htm), but there is
no dark shading, so the impression one gets in the field is different (i.e.
that of plain grey tertials). There may be exceptions, but generally this
seems to be a fairly simple and fairly consistent difference.
Interestingly, the New York hybrid teal has a tertial pattern that is
somewhat intermediate, showing some brownish shading along the shafts.
Best regards,
Peter Adriaens
Belgium
[ << | >> | ^^ ]
Subject: Peters World checklist
From: ian paulsen <ipaulsen(AT)KRL.ORG>
Date: 29 Mar 2002 12:18pm
HI ALL:
Does anyone have a copy of Peters World Checklist of Birds?? If so could
you please check to see if he treats the Green Pheasant (P. versicolor) as
a valid species??
Thanks!
Ian Paulsen
Bainbridge Island, WA, USA
ipaulsen(AT)krl.org
A.K.A.: "Birdbooker"
"Rallidae all the way"
[ << | >> | ^^ ]
Subject: yellow-legged Great Black-backed Gulls
From: Bruce Mactavish <bruce.mactavish1(AT)NF.SYMPATICO.CA>
Date: 31 Mar 2002 5:58am
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While scanning a sea of gull legs nicely displayed by a large mixed
flock of gulls standing on a frozen lake in St. John's, Newfoundland on
March 27, I came across an adult Great Black-backed Gull with yellow
legs. Distinctly yellow as in a very dull winter adult Ring-billed Gull
or a like a dull winter adult Lesser Black-backed Gull. No matter how I
tried to see pink they stayed distinctly, uniform clear yellow without a
hint of the pink, or pink-gray that a GBBGs legs should be. There were
many sets of adult GBBG, HEGU, GLGU and ICGU for direct comparison but
that only reinforced the yellow appearance. The tibia, 'knee joint' and
tarsus were solidly yellow. A dull or dingy, but clean and uniform,
lemon yellow. No dusky marks. The feet appeared yellow as well but were
at a difficult angle to see well. Viewing conditions were excellent -
overcast sky with reflecting light off white ice enhancing lighting on
undersides of gulls. The wingtip pattern, mantle colour and overall
build and shape were wholly typical for Great Black-backed Gull. There
was no indication of a hybrid or Kelp Gull.
I proceeded to scope the several thousand gulls concentrating on GBBGs
and found another yellow-legged Great Black-backed Gull! The leg colour
being so similar to the first bird that I thought it must be the same
bird. But the presence of a dusky mark on the gonydeal spot and slight
remnants of winter head streaking confirmed that it was different
individual. Leg colour as first bird. Wing tip pattern, mantle colour
and structure standard for GBBG.
On March 29 I was back at the same lake scanning a smaller gull flock.
I carefully looked at the legs of 300 adult GBBGs and found one with
distinct yellow-green legs. Again very different among the other pink
and pinkish-gray legged GBBG, HEGU, GLGU, ICGU present for direct
comparison. Again everything else about the bird was typical GBBG.
I have not completely ignored the legs of GBBGs in the past, but am
surprised by two with yellow legs and one with yellow-green legs in a
three day period after noting none other than the standard pink or
pink-gray for years. I suspect it is a brief condition caused by the
approaching breeding season and hyper-active hormones. Local Herring
Gulls have a similar reaction to the breeding season. In March and
April the bills and legs of some Herring Gulls warm up. The bills
become brighter orange. The legs on a few develop a yellowish veneer
over the pink. On others it is more than a veneer and looks solid pale
yellow like the colour of uncooked chicken fat or straw-yellow. This
yellow may be more than just a wash, but it no where near the intensity
of a breeding Lesser Black-backed Gull or Ring-billed Gull. It seems to
last only for a few months at the start of the breeding season. But if
Herring Gull and, as it seems, Great Black-backed Gull can transform
normal pinkish legs into yellowish or yellow legs in the breeding season
then perhaps an unbalanced individual could do it at any season.
Therefore beware of yellow-legged smithsonianus Herring Gulls and Great
Black-backed Gulls
BM
Bruce Mactavish
St. John's, Newfoundland
Canada
bruce.mactavish1(AT)nf.sympatico.ca
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[ << | >> | ^^ ]
Subject: Aberrant Franklin's or Hybrid?
From: Tristan Reid <brown.flycatcher(AT)BTOPENWORLD.COM>
Date: 31 Mar 2002 6:45am
Hi All,
Thank you to all members of this list who responded to my query about
Franklin's Gull mantle colour variation.
My reason for making this enquiry was because of a Gull found at Draycote
Water UK. This Gull for all intense and purposes resembled a pale mantled
Franklin's Gull.
So my question is, is this an aberrant Franklin's Gull or is this a hybrid?
If it is a hybrid, then what is its parentage?
Images of the bird can be viewed on the following URL:
http://www.surfbirds.com/Rarities/draycote-gull-0302.html
Any constructive comments would be helpful!
Thank you in advance.
Regards
Tristan Reid
[ << | >> | ^^ ]
Subject: UNSUBSCRIBE
From: Janus Andersen <cja(AT)POST10.TELE.DK>
Date: 31 Mar 2002 7:13am
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UNSUBSCRIBE
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[ << | >> | ^^ ]
Subject: Re: Aberrant Franklin's or Hybrid?
From: Millington/BIS <sales(AT)birdingworld.co.uk>
Date: 31 Mar 2002 8:28am
Hi all
With regard to the odd gull at Draycote Water, UK,
I guess Common X Mediterranean Gull hybrid would cover it,
and neatly explain everything visible in these pictures.
Such a hybrid possibility has been reported before
and does seem the easiest explanation.
Of course the odd Franklin's Gull could end up in a Common Gull colony
(just as we know Laughing gets in with Ring-billed and Black-headeds),
but maybe that is stretching feasibility a little?
cheers
Richard
...........................
sales(AT)birdingworld.co.uk
(Birding World, Books for Birders & Birdline)
Bird Information Service, Stonerunner, Coast Road,
Cley next the Sea, Holt, Norfolk, NR25 7RZ, UK
Tel. 44 (0) 1263 741139 Fax. 741173
Website www.birdingworld.co.uk
Re. Original Message :
From: Tristan Reid Date: 31 March 2002 14:46
>So my question is, is this an aberrant Franklin's Gull or is this a hybrid?
>If it is a hybrid, then what is its parentage?
>Images of the bird can be viewed on the following URL:
>http://www.surfbirds.com/Rarities/draycote-gull-0302.html
[ << | >> | ^^ ]
Subject: Leg Color and Spring Bloom in Ring-billed Gulls
From: John Idzikowski <idzikoj(AT)UWM.EDU>
Date: 31 Mar 2002 10:57am
Bruce Mactavish's observations about leg color in GBBG are similar to what I
have been seeing among the thousands of adult Ring-billed Gulls moving
through the western Great Lakes. While the physiological mechanism may be
the same there is little potential ID confusion caused by this change in
RBGU. The pinkish cast to the white body feathers in some RBGU in the
alternate plumage is well known, but it is still rather rare. I have been
seeing about 1 in 600-800 adults so bloomed apparently due to pigments in
preen gland secretions and of those there seems to be variation in the
amount of further pinkish-orange suffusion of both the bill, legs and feet,
apparently from internal changes as in a few GBBG. One such well-bloomed and
suffused adult was seen on March 26 in Milwaukee; a few digitals are in the
"Gull" album at
http://community.webshots.com/user/idzikoj
John Idzikowski, Milwaukee
[ << | >> | ^^ ]
Subject: Re: yellow-legged Great Black-backed Gulls
From: "Norman D.van Swelm" <Norman.vanswelm(AT)WXS.NL>
Date: 31 Mar 2002 3:53pm
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=20
=20
Bruce wrote:>While scanning a sea of gull legs nicely displayed by a =
large mixed flock of gulls standing on a frozen lake in St. John=92s, =
Newfoundland on March 27, I came across an adult Great Black-backed Gull =
with yellow legs. Distinctly yellow as in a very dull winter adult =
Ring-billed Gull or a like a dull winter adult Lesser Black-backed Gull. =
No matter how I tried to see pink they stayed distinctly, uniform clear =
yellow without a hint of the pink, or pink-gray that a GBBGs legs should =
be. -....- There was no indication of a hybrid or Kelp Gull. <
=20
Some time ago, in a raging storm, many adult Great Blacks came =
ashore near where I live in The Netherlands. The legs of one bird seem =
to have a vague yellowish glow on them. It also had a particularly =
thick-set bill. The picture I took made me none the wiser but I still =
feel there was a Kelpish element in it!
Norman
=20
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[ << | >> | ^^ ]
Subject: Teal and scoter variation
From: "Norman D.van Swelm" <Norman.vanswelm(AT)WXS.NL>
Date: 31 Mar 2002 4:21pm
Just to let you know I found a male Green-winged Teal A.crecca this week
with neither a horizontal nor a vertical stripe on the sides! It did have a
pale line along the top of the green facial area.
On three occasions I found male Common Scoters Melanitta nigra with a larger
than normal amount of yellow on the knob and lower part of the upper
mandible. On the basis of a dead bird I found in 1968, the late
Prof.K.H.Voous wrote a note in the Dutch magazine Ardea wherein he suggested
this could be a hybrid nigra x americana originating from the area in NE
Siberia where the ranges of the nigra and americana meet. Has there been
reports of unusual americana's in Canada or the USA?
Norman
[ << | >> | ^^ ]
Subject: Re: Eurasian Wigeon numbers and hybrids
From: Steven Mlodinow <SGMlod(AT)AOL.COM>
Date: 31 Mar 2002 6:07pm
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Greetings All
I appreciate the comments of Wayne Weber on the variability of pure Eur
Wigeon. I must stress, however, that the 5-6 hybrid wigeon seen at Samish
Island were truly hybrids. Indeed, I've found the 20:1 pure Eurasian:hybrid
ratio to hold up fairly consistently in w. WA and in sw. BC. Furthermore,
some other skilled birders (from both BC and WA) have suggested that hybrid
wigeon may be even a bit more numerous.
Cheers
Steve Mlodinow
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[ << | >> | ^^ ]
Subject: Re: FW: Hybrids Green-winged x
Eurasian teals (A.caroli...
From: Steven Mlodinow <SGMlod(AT)AOL.COM>
Date: 31 Mar 2002 6:14pm
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Greetings All
Re: Eur and Am GW Teal-- I'd be most curious if anyone knows of a reliable
way of identifying females. I am not aware of such, and so to be honest, have
not really tried.
As for hybrids between these two, the ones I am able to ID are obvious. They
have a thick white horizontal stripe on the side (much like the Eur) and have
a variable vertical stripe -- sometimes faint, sometimes as bold as a typical
Amer. These birds can have the facial pattern, vermiculations, and rear-flank
pattern of either parent. I am sure that backcrosses (or otherwise more
subtle integrades) might be easily missed by me. But the classic bird is
obvious and are well depicted in Sibley's guide.
Cheers
Steven Mlodinow
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