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ID-FRONTIERS for August 18-24, 2002
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Messages are displayed in the order they were received.
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| Subject | From | Date | Time |
| Caracara Comments | Alan Wormington | Sun, 18 Aug 2002 | 6:58am |
| Re: Caracara Comments | Ned Brinkley | Sun, 18 Aug 2002 | 7:27am |
| Re: Caracara Comments | Sebastian Patti | Sun, 18 Aug 2002 | 7:35am |
| Re: Caracara | Bob & Carol Yutzy | Sun, 18 Aug 2002 | 11:39am |
| Re: Caracara | Alvaro Jaramillo | Sun, 18 Aug 2002 | 6:40pm |
| Re: Caracara | Dave Compton | Sun, 18 Aug 2002 | 7:40pm |
| Re: Caracara | Phil Davis | Sun, 18 Aug 2002 | 9:08pm |
| Re: Caracara | Floyd Hayes | Mon, 19 Aug 2002 | 7:06am |
| Another Atlantic Elegant-Like Tern | Noel Wamer | Mon, 19 Aug 2002 | 11:21am |
| Re: Caracara | John C. Arvin | Mon, 19 Aug 2002 | 2:48pm |
| Re: Another Atlantic Elegant-Like Tern | Martin Reid | Mon, 19 Aug 2002 | 2:50pm |
| Re: Another Atlantic Elegant-Like Tern | Glenn A dEntremont | Mon, 19 Aug 2002 | 6:30pm |
| Re: Another Atlantic Elegant-Like Tern | Floyd Hayes | Tue, 20 Aug 2002 | 7:42am |
| Western NA race of Green Heron | Floyd Hayes | Tue, 20 Aug 2002 | 8:20am |
| Brachyramphus Murrelet question (fwd) | ian paulsen | Tue, 20 Aug 2002 | 10:49am |
| Caracara range expansion | Matt White | Tue, 20 Aug 2002 | 11:29am |
| juvenile goldfinches | ian paulsen | Wed, 21 Aug 2002 | 8:34pm |
| Re: Another Atlantic Elegant-Like Tern | Floyd Hayes | Thu, 22 Aug 2002 | 7:23am |
| Elegant vs Lesser Crested | Julian Hough | Thu, 22 Aug 2002 | 9:04am |
| Re: Elegant vs Lesser Crested | Alvaro Jaramillo | Thu, 22 Aug 2002 | 11:26am |
| Juvenile Pine Siskin vs. Lawrence's Goldfinch | Ted Floyd | Thu, 22 Aug 2002 | 12:48pm |
| Re: Elegant vs Lesser Crested | miguel demeulemeeste | Thu, 22 Aug 2002 | 1:28pm |
| Re: Elegant vs Lesser Crested | Richard Heil | Thu, 22 Aug 2002 | 5:37pm |
| Re: Elegant vs Lesser Crested | Glenn A dEntremont | Thu, 22 Aug 2002 | 6:36pm |
| Re: Elegant vs Lesser Crested | Phil Davis | Thu, 22 Aug 2002 | 7:47pm |
| Re: Elegant vs Lesser Crested | Andy Guthrie | Thu, 22 Aug 2002 | 8:19pm |
| Re: Elegant vs Lesser Crested | Don Crockett | Thu, 22 Aug 2002 | 9:04pm |
| Re: Elegant vs Lesser Crested | Don Crockett | Thu, 22 Aug 2002 | 9:23pm |
| Re: Elegant vs Lesser Crested | Don Roberson | Fri, 23 Aug 2002 | 8:14am |
| Digital photos and bird ID (off topic & long) | Matt Sharp | Fri, 23 Aug 2002 | 8:24am |
| Re: Elegant vs Lesser Crested | Tony Leukering | Fri, 23 Aug 2002 | 8:45am |
| Re: Digital photos and bird ID (off topic & long) | Joseph Morlan | Fri, 23 Aug 2002 | 9:31am |
| Re: Elegant vs Lesser Crested | Clay Taylor | Fri, 23 Aug 2002 | 11:47am |
| Re: Digital photos and bird ID (off topic & long) | Phil Jeffrey | Fri, 23 Aug 2002 | 1:11pm |
| Re: Elegant vs Lesser Crested | Don Crockett | Fri, 23 Aug 2002 | 2:48pm |
| Image quality in jpegs | John Idzikowski | Fri, 23 Aug 2002 | 11:04pm |
| Elegant Tern specimens at MCZ | Blair Nikula | Sat, 24 Aug 2002 | 5:26pm |
| Re: Elegant vs Lesser Crested - long | Martin Reid | Sat, 24 Aug 2002 | 6:36pm |
| Elegant Tern - yet again! | Blair Nikula | Sat, 24 Aug 2002 | 6:43pm |
| Re: Elegant vs Lesser Crested | Floyd Hayes | Sat, 24 Aug 2002 | 7:45pm |
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[ << | >> | ^^ ]
Subject: Caracara Comments
From: Alan Wormington <wormington(AT)JUNO.COM>
Date: 18 Aug 2002 6:58am
Here is some information that suggests most extralimital records of Caracara
pertain to WILD birds:
There are now three records of Caracara in Ontario, all during the unlikely
month of JULY.
The most recent record was this year when a bird was present for over a week at
Fort Albany, which is on James Bay in northern Ontario (I'm not even sure if
Turkey Vulture has ever occurred at this northern, boreal location!). The
nearest road access to this town is at least 250 miles away.
About 10 years ago, Ontario's second record was a bird seen at Pelee Island,
western Lake Erie. The SAME WEEK another Caracara was reported in Minnesota.
Ontario's first record of Caracara was before the turn of the century (1890s? -
I don't have access to the exact info at the moment) when a dead bird was found
on a very remote island in the western end of Lake Superior "after a terrific
southwest gale."
None of these records have the characteristics of birds that have escaped from
activity. In contrast, we must accept that Caracara does wander and can
conceivably occur anywhere in North America.
Alan Wormington,
Leamington, Ontario
[ << | >> | ^^ ]
Subject: Re: Caracara Comments
From: Ned Brinkley <Phoebetria(AT)AOL.COM>
Date: 18 Aug 2002 7:27am
I agree with Alan Wormington's inclination toward openmindedness on
Crested/Northern Caracara wanderings in North America. In the late 1970s, a
Caracara escaped from the Norfolk [Virginia] Zoo and was observed at nearby
Lambert's Point and around landfills. It was not recaptured and shied from
approach. If memory serves, this bird was of the Northern taxon.
The question this raises for me is: how long might such an individual survive
at various latitudes? What would its propensity to wander be? And how might
weather phenomena influence where it turns up (or is noticed)? All of these
questions could be put regarding a whole range of species kept in captivity.
One thinks of the records of Chilean Flamingos wildly out of range: they
appear to outnumber records of American Flamingo in Virginia in the past
quarter-century, for instance, and one even made it as far as Iceland. There
is one published paper that holds open the possibility of such birds being
legitimate vagrants (Lee, David S. 1987. Long-legged pink things: What are
they? Where do they come from? Chat 51: 43-48), but most authors categorize
these birds as probable escapees from captivity. It is interesting that
hurricanes' and tropical storms' passage are often linked to the appearance
of "vagrant" flamingos in the East, whether American or unAmerican.
Ned Brinkley
Cape Charles, Virginia, USA
[ << | >> | ^^ ]
Subject: Re: Caracara Comments
From: Sebastian Patti <sebastianpatti(AT)HOTMAIL.COM>
Date: 18 Aug 2002 7:35am
. . . reminds me of the discussions in some list-serves regarding Harris'
Hawk and Black-bellied Whistling Duck . . .
>From: Alan Wormington <wormington(AT)JUNO.COM>
>Reply-To: wormington(AT)JUNO.COM
>To: BIRDWG01(AT)listserv.arizona.edu
>Subject: [BIRDWG01] Caracara Comments
>Date: Sun, 18 Aug 2002 13:57:43 GMT
>
>Here is some information that suggests most extralimital records of
>Caracara pertain to WILD birds:
>
>There are now three records of Caracara in Ontario, all during the unlikely
>month of JULY.
>
>The most recent record was this year when a bird was present for over a
>week at Fort Albany, which is on James Bay in northern Ontario (I'm not
>even sure if Turkey Vulture has ever occurred at this northern, boreal
>location!). The nearest road access to this town is at least 250 miles
>away.
>
>About 10 years ago, Ontario's second record was a bird seen at Pelee
>Island, western Lake Erie. The SAME WEEK another Caracara was reported in
>Minnesota.
>
>Ontario's first record of Caracara was before the turn of the century
>(1890s? - I don't have access to the exact info at the moment) when a dead
>bird was found on a very remote island in the western end of Lake Superior
>"after a terrific southwest gale."
>
>None of these records have the characteristics of birds that have escaped
>from activity. In contrast, we must accept that Caracara does wander and
>can conceivably occur anywhere in North America.
>
>Alan Wormington,
>Leamington, Ontario
sebastianpatti(AT)hotmail.com
Sebastian T. Patti
(Lincoln Park)
Chicago, ILLINOIS 60614-3354
PHONE: 312/603-4416 (o) 773/248-0570 (h)
FAX: 312/603-2041 (o) 773/248-0264 (h)
_________________________________________________________________
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[ << | >> | ^^ ]
Subject: Re: Caracara
From: Bob & Carol Yutzy <boby(AT)C-ZONE.NET>
Date: 18 Aug 2002 11:39am
I am certainly far from expert in this area - but know a little about Texas
Caracara's. I am very uncomfortable with these being wild birds. Where is the
pattern of birds ranging wider and wider from their known area - with good
records showing their presence.
Whether there are five birds or not - where are the San Diego records,
expabsion
of Arizona and Texas records from known areas, etc.
Wouldn't we require those records before accepting these birds as truly wild?
This was a species that was fairly regularly kept in captivity, wasn't it?
Just my two cents worth,
Bob Y.
Bill Hill wrote:
> Early this week we had a Caracara near Marina in Monterey California. Last
> month there was one at Vandenberg in Santa Barbara County and today they had
> another. that is a total of 5 in a year in that County. This raises the
> question of where are these birds coming from. In the past Caracara in
> California have been considered escapees and are on the Supplemental list.
> Any thoughts on this high number of sightings in one year. Pictures of the
> Monterey County bird are available at.
> http://fp2k.redshift.com/billhill/new_page_5.htm
> We are considering this to be a first basic bird but any comments would be
> welcome.
>
> I am new to your forum and hope that this is an appropriate topic
>
> Bill Hill
> Carmel California
[ << | >> | ^^ ]
Subject: Re: Caracara
From: Alvaro Jaramillo <chucao(AT)ATTBI.COM>
Date: 18 Aug 2002 6:40pm
At 11:38 AM 8/18/2002 -0700, Bob & Carol Yutzy wrote:
>I am certainly far from expert in this area - but know a little about Texas
>Caracara's. I am very uncomfortable with these being wild birds. Where
>is the
>pattern of birds ranging wider and wider from their known area - with good
>records showing their presence.
>
>Whether there are five birds or not - where are the San Diego records,
>expabsion
>of Arizona and Texas records from known areas, etc.
>
>Wouldn't we require those records before accepting these birds as truly wild?
>
>This was a species that was fairly regularly kept in captivity, wasn't it?
Bob et al.
Feel odd about commenting on this subject on a list that is supposed to
be dealing with bird ID. Perhaps its best to take this discussion
elsewhere? In any case the other day at a bird observatory meeting I asked
biologist and falconer Doug Bell about what he knew about caracaras in
captivity. He knows a lot of the raptor people and knows what they keep. He
thought that a caracara held little interest to a falconer and that few if
any would keep one. Basically its not a very exciting bird, you can't make
it hunt anything. However general aviculturalists and zoos would be more
likely to have a species like this. At least with zoos one can check to see
if any are missing, and these birds are also likely to have leg bands of
some kind. When I asked him how many he thought were in captivity in
California, his guess was that it was in the "tens" not the "hundreds". So
if five (or whatever the number is) have been seen in a year, this is
significant. It makes it less likely that they are escapees.
With regards to the age of the Monterey bird I do think its in its first
basic, undergoing the second prebasic (definitive prebasic) moult so very
soon it will be an adult (definitive basic). The key points to look at are
the brown cap, the buffy wash to the neck as opposed to white, and the fact
that the breast and neck base are not clearly barred like an adult. This
part of the bird is streaked on a juvenile, intermediate in first basic,
and clearly barred on the adult. Juveniles also have grey legs. The face
colours are useful in ageing, but can change depending on the mood of the
bird so you have to keep that in mind.
It would be interesting to get details from people who do keep raptors in
captivity to detail how moult occurs, and if it is synched up in the
natural time frame as compared to wild birds. Apparently falconers can't
fly their birds during moult, so its a part of their biology that they keep
good track of. I don't know much about Crested Caracara moult, but it would
appear that the Monterey Bird is moulting roughly in the right time frame -
is that correct?
Al
Alvaro Jaramillo
Biologist
San Francisco Bay Bird Observatory
P.O. Box 247
Alviso, CA 95002
(408)-946-6548
http://www.sfbbo.org/
chucao(AT)attbi.com
[ << | >> | ^^ ]
Subject: Re: Caracara
From: Dave Compton <davcompton(AT)EARTHLINK.NET>
Date: 18 Aug 2002 7:40pm
So if five (or whatever the number is) have been seen in a year, this is
significant. It makes it less likely that they are escapees.
My apologies, since this is again away from the ID aspect of this whole
debate, but I thought it was important to correct a misconception that's
going around on this list, that there have been five different caracaras in
Santa Barbara County in the past year. Caracaras have been seen at five
different locations, widely dispersed across the coastal portion of the
county, with all but one of these records involving one-time sightings and
the majority involving poorly documented birds. For all I know, they could
all be the same bird.
Dave Compton
[ << | >> | ^^ ]
Subject: Re: Caracara
From: Phil Davis <pdavis(AT)IX.NETCOM.COM>
Date: 18 Aug 2002 9:08pm
Al, et al. -
If anyone wants to move the discussion over to the Bird Records Committee
Forum - Listerserver (BRCF-L), feel free.
The web site for subscription and background info is here ...
http://www.princeton.edu/~llarson/brcf/brcfhome.html
Phil
At 06:29 PM 08/18/2002 -0700, Alvaro Jaramillo wrote:
Feel odd about commenting on this subject on a list that is supposed to
>be dealing with bird ID. Perhaps its best to take this discussion
>elsewhere?
==================================
=========================================================
Phil Davis
Davidsonville, Maryland USA
mailto:PDavis(AT)ix.netcom.com
Co-Listowner, Bird Records Committee Forum
BRCF home page: http://www.princeton.edu/~llarson/brcf/brcfhome.html
Secretary, Maryland/DC Records Committee
MD/DCRC web site: http://www.MDBirds.org/mddcrc/rcindex.html
=========================================================
[ << | >> | ^^ ]
Subject: Re: Caracara
From: Floyd Hayes <floyd_hayes(AT)HOTMAIL.COM>
Date: 19 Aug 2002 7:06am
Although we may think of Crested Caracara as a tropical species in the
northern hemisphere, it thrives in temperate latitudes of southern South
America. Is there any reason why it shouldn't be gradually expanding its
range northward?
-Floyd
_________________________________________________________________
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[ << | >> | ^^ ]
Subject: Another Atlantic Elegant-Like Tern
From: Noel Wamer <nwamer(AT)ATTBI.COM>
Date: 19 Aug 2002 11:21am
Those who are interested in enigmatic, large, orange-billed terns on
Atlantic shores might want to know that there is currently one in
Massachusetts. It was identified as an Elegant, but seems to have a gray
rump similar to the mantle color. Links to three sets of pictures...
Standing bird:
http://home.attbi.com/~odenews/ElegantTernChatham.htm
http://larsonweb.org/birds/southbeach081802.html
In flight, or about to be:
http://www.virtualbirder.com/vbirder/rba/elte
As always, comments will be appreciated.
Later...
Noel Wamer
Jacksonville, FL, US
Mosaics by Noel & Terry - http://home.attbi.com/~terrywest/
[ << | >> | ^^ ]
Subject: Re: Caracara
From: "John C. Arvin" <JohnCArvin(AT)AOL.COM>
Date: 19 Aug 2002 2:48pm
Again, not an identification issue, but in Texas, where the lion's share of
U. S. Crested Caracaras reside, a modest range expansion is occurring. It
pales by comparison to the galloping northward range extensions currently
underway by many subtropical species across the taxonomic board (White-tipped
Dove, Ringed Kingfisher, Buff-bellied Hummingbird, Great Kiskadee, Tropical
Kingbird, Couch's Kingbird, Clay-colored Robin, Tropical Parula, etc., etc.).
Currently the caracara is inching northward through the east-central part of
the state, bringing it into areas south and southeast of Dallas. I don't know
if extralimital records exist and/or have increased in nearby Oklahoma. I
believe that recent records exist, but are not numerous for southwestern
Louisiana. I am not aware of increasing reports from far west Texas (Big
Bend-El Paso). Extralimital records in California and elsewhere (Ontario?!)
would not seem to be part of a general northward expansion of the
Texas/eastern Mexico population. Floyd is quite correct in pointing out that
Crested, or "Southern" Caracara of some authors, occurs commonly in the south
temperate zone. I have observed them commonly in Tierra del Fuego which is a
sort of mirror image of southeastern Alaska from a climate standpoint.
John Arvin
Chairman, Texas Bird Records Committee
[ << | >> | ^^ ]
Subject: Re: Another Atlantic Elegant-Like Tern
From: Martin Reid <upupa(AT)AIRMAIL.NET>
Date: 19 Aug 2002 2:50pm
Dear all,
Most interesting indeed. From the first images and descriptions, it looked
to be a pretty good ELTE, but those flight shots in the 3rd URL provided
do indeed show a uniform gray rump - so why isn't this a Lesser Crested Tern?
The mantle looks to be VERY close to that of accompanying COTEs -
especially in Blair Nikula's original images, which are also the best ones
to assess this, being fairly close and with the birds close-together and at
virtually the same angle. Now look at the mantles on the provided skins on
Blair's web page; the lighter LCTE is the same shade as the COTEs, and a
younger LCTE would be expected to be a bit paler. Note that the birds
breeding in the Med. Sea are the palest form of LCTE, and an imm. bird
heading out of the Straits of Gibraltar - if it kept going instead of
turning south, it would end up in New England or adjacent Canada.
In fact the only feature I can see that looks a bit wrong for LCTE is the
lack of any pale eye-crescent behind the eye - I wonder how variable this
is in the Med. population; perhaps some European experts could comment?
The concolorous rump would also seem to rule out any SATE x ELTE hybrid, so
I am left thinking that this is indeed a LCTE - what am I missing here?
Cheers,
Martin
At 8/19/2002 02:19 PM -0400, Noel wrote:
>Those who are interested in enigmatic, large, orange-billed terns on
>Atlantic shores might want to know that there is currently one in
>Massachusetts. It was identified as an Elegant, but seems to have a gray
>rump similar to the mantle color. Links to three sets of pictures...
>
>Standing bird:
>http://home.attbi.com/~odenews/ElegantTernChatham.htm
>http://larsonweb.org/birds/southbeach081802.html
>
>In flight, or about to be:
>http://www.virtualbirder.com/vbirder/rba/elte
>
>As always, comments will be appreciated.
>Later...
>
>Noel Wamer
>Jacksonville, FL, US
>Mosaics by Noel & Terry - http://home.attbi.com/~terrywest/
Martin Reid
Fort Worth, Texas
upupa(AT)airmail.net
http://www.martinreid.com
[ << | >> | ^^ ]
Subject: Re: Another Atlantic Elegant-Like Tern
From: Glenn A dEntremont <gdentremont(AT)JUNO.COM>
Date: 19 Aug 2002 6:30pm
Folks, seeing this bird live makes me a little qualified to address the
below issues.
First, the bird was paler than Common and darker than Roseate. The bird
was about 10 percent larger overall from Common. The rump was white
contrasting with the mantle. This was seen both in flight and during
stretching that the bird did while being watched within 100 feet (perhaps
a bit farther). As to the skins, the two, numbers 3 and 4 from the left,
more accurately show what the bird in life showed on 8/17 in both
coloration of the upperparts and length of bird in comparision to the
live Commons. Please note that these two are the Elegants! Compare with
the last two on the right. These are the Commons.
The flight shots do indeed show a paler bird than Common and do show a
white rump. See Flight 1and Flight 4. I can not explain Flight 5, but
compare with 1 & 4, it is not accurate on the rump. Flight 4 and 5 are
fuzzy probably due to distance, digital imaging, and heat shimmer.
For a good image of how the bird appears in overall shape, shape of bill,
color of bill, see picture 63 in TERNS of Europe and North America, Olsen
and Larsson. Picture 48 (Lesser Crested Tern) is too thin, the bill too
short, the bird too dark, and the bill too yellow. In fact, all the
Lesser Crested Tern shown have much too yellow bills and the mantles of
all the sitting birds are too dark. Please note that even the paler
Lesser Crested of the skins is as dark as the Commons.
Hope this helps.
Glenn
On Mon, 19 Aug 2002 16:54:27 -0500 Martin Reid <upupa(AT)AIRMAIL.NET>
writes:
> Dear all,
> Most interesting indeed. From the first images and descriptions, it
> looked
> to be a pretty good ELTE, but those flight shots in the 3rd URL
> provided
> do indeed show a uniform gray rump - so why isn't this a Lesser
> Crested Tern?
> The mantle looks to be VERY close to that of accompanying COTEs -
> especially in Blair Nikula's original images, which are also the
> best ones
> to assess this, being fairly close and with the birds close-together
> and at
> virtually the same angle. Now look at the mantles on the provided
> skins on
> Blair's web page; the lighter LCTE is the same shade as the COTEs,
> and a
> younger LCTE would be expected to be a bit paler.
Glenn d'Entremont
gdentremont(AT)juno.com
Stoughton, MA
[ << | >> | ^^ ]
Subject: Re: Another Atlantic Elegant-Like Tern
From: Floyd Hayes <floyd_hayes(AT)HOTMAIL.COM>
Date: 20 Aug 2002 7:42am
I concur with Martin's assessment of rump color, which appears consistently
gray in all five photos (1, 2, 4-6). In flight photo #4, five of the COTEs
show a contrastingly white rump, but perplexingly the COTE at lower right
appears to have a darker rump, perhaps due to the steep angle. The
Elegant-like Tern is flying at the same angle toward the camera as the COTEs
immediately above right and below right, yet the latter two birds have
contrastingly white rumps. In this case I don't think the photos are
misleading us.
-Floyd
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[ << | >> | ^^ ]
Subject: Western NA race of Green Heron
From: Floyd Hayes <floyd_hayes(AT)HOTMAIL.COM>
Date: 20 Aug 2002 8:20am
Do birders in western North America ever seen Green Herons as pale as the
adult Butorides virescens anthonyi from California illustrated in fig. 8, p.
6, of North American Birds 56(1)? I'm wondering if this bird is simply an
extremely pale individual beyond the range of variation in specimens of
anthonyi examined by Payne, or whether the photo is slightly overexposed
(wing feathers seem paler than those in other photos in article). I often
see such birds here in Trinidad and Tobago, which I would score as a "4" on
Payne's index and conclude that they were either rufous-necked extremes of
Striated Heron (did birders miss one in California?!) or hybrid Green X
Striated Heron.
-Floyd
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[ << | >> | ^^ ]
Subject: Brachyramphus Murrelet question (fwd)
From: ian paulsen <ipaulsen(AT)KRL.ORG>
Date: 20 Aug 2002 10:49am
HI ALL:
Can anyone help this guy out?
Ian Paulsen
Bainbridge Island, WA, USA
ipaulsen(AT)krl.org
A.K.A.: "Birdbooker"
"Rallidae all the way"
---------- Forwarded message ----------
Date: Mon, 19 Aug 2002 23:26:54 -0700
From: Gavin Bieber <kingbird77(AT)hotmail.com>
To: ipaulsen(AT)krl.org
Subject: Brachyramphus Murrelet question
Hello Ian Paulsen,
We have not, to my knowledge ever met, but I have noticed that you will
often take requests to forward questions to listserves. My name is Gavin
Bieber, from Victoria BC (and now in Tucson AZ). I have spent the summer as
a bird guide on St. Paul in the Pribilof Islands, AK. I have a bird
identification question that I would appreciate some thoughts on from ID
frontiers, and perhaps a listserve that might deal with Japanese birding or
contain folks with direct knowledge of Long-billed Murrelets.
Earlier today while birding near town on St. Paul I noticed a Brachyramphus
murrelet close to shore. The bird was in flight for the duration of the
sighting (1.5 minutes) and initially was 50m offshore. It is worth noting
that there are no expected Brachyramphus sp. for St. Paul, and such birds
have been seen only twice that I know of this decade. Both "marbled" and
Kittlitz's are on the island checklist, but it is concievable that some or
all of the "marbled" murrelets were in fact Long-billed murrelets sen
pre-split.
I had good views of the entire dorsal surface of the bird, including tail
pattern, and also of the underwing and flanks. I had fair views of the
birds head.
Features Noted.
The bird was approximately the size of a Parakeet Auklet, although much more
slender in overall body shape and with a pointed (more attenuated)head and
longer more tapered wings. The dorsal surface of the bird was a uniform
black/blue.The throat, flanks and undertail were clean white. No trace of
white was seen at the edges of the tail or around the eyes (although the
view of the face was very brief). The center of the birds underwings were
white graded to a dusky white above and below the center (giving the
underwing a white bar in the center of the wing, bordered by dark primaries
and secondaries and a dark leading edge to the wing). It is my
understanding that Long-billed Murrelet will show a variable amount of white
in the underwing, while marbled and Kittlitz's Murrelet will show an all
dark underwing. I have seen many MAMU's in the Puget sound but I cannot
remember even paying much attention to underwing patterns.
Given these details I am not sure that a positive identification can be
reached. Can anyone offer any insight with regards to flight identification
of these species and/or distribution of these spescies in the Bering Sea
region?
Thanks in advance for your help,
Gavin Bieber
Kingbird77(AT)hotmail.com
St. Paul Island AK
_________________________________________________________________
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[ << | >> | ^^ ]
Subject: Caracara range expansion
From: Matt White <mkwhite(AT)903INTERNET.COM>
Date: 20 Aug 2002 11:29am
This is a multi-part message in MIME format.
----INCLUDING text/plain MIME SECTION----
Hello=20
The recent thread concerning Caracara is quite interesting and while it =
may not be strictly an ID issue, I wanted to chime in with a viewpoint =
that has not been expressed previously. As one who lives on the =
northern edge of the precise border of the Caracara's known range which =
is (at the moment), northeast of Dallas in Hunt, Fannin, Hopkins and =
Delta counties, just mere miles south of the Red River, I can say with =
no hesitation that this species is more much abundant and widespread =
here that it was even 5 years ago. In fact, there has been an explosive =
population increase here in the past few years with birds being seen =
much more frequently and in greater numbers. There are also a number =
of records recently from Fort Worth and areas to the northwest of there =
where they also seem to be increasing. Although Oklahoma has no =
documented records yet (with photos) there are several reports in that =
state. I feel certain though that they are in SC Okla regularly now, =
but that state is sparsely populated with birders. =20
Because they still do not occur with the same density here that they =
do in south Texas, this species is still easily overlooked even here, =
and would be, in my opinion, a classic candidate for a stealth vagrant =
elsewhere. This may explain why there are few records away from the =
central US but there are records from Ontario, South Dakota, etc. The =
same pattern has recently been demonstated with Cave Swallows in New =
Jersey and along the East Coast. Great Plains birders in particular, =
and others should be on the lookout. Here they seem really fond of =
cattle pastures and lakeshores (eating dead fish) and are often seen on =
the ground. I expect these birds are coming your way (sooner rather =
than later). Just my two cents...
Matt White
Campbell Texas
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[ << | >> | ^^ ]
Subject: juvenile goldfinches
From: ian paulsen <ipaulsen(AT)KRL.ORG>
Date: 21 Aug 2002 8:34pm
HI ALL:
I was reading the answers to june's photo quiz in the August issue of
Birding magazine and noticed the answer to Quiz B bird as juvenile
Lawrence's Goldfinch. I noticed how similar it is to Pine Siskins. So I
went to the guide books for answers on how to separate the juvenile
goldfinches/siskin apart. The Sibley guide DOESN'T illustrate them and the
National Geographic (third edition) illustrations aren't that good! So
does anyone have a source for good illustrations of juvenile
goldfinches/siskin and how to separate them? ALso I understand that the
National Geographic fourth edition is due out in November and I was
wondering what changes have been made to it? Better plates I hope!
sincerely
Ian Paulsen
Bainbridge Island, WA, USA
ipaulsen(AT)krl.org
A.K.A.: "Birdbooker"
"Rallidae all the way"
[ << | >> | ^^ ]
Subject: Re: Another Atlantic Elegant-Like Tern
From: Floyd Hayes <floyd_hayes(AT)YAHOO.COM>
Date: 22 Aug 2002 7:23am
I'm puzzled by the lack of chatter on the identity of
a possible new species for the New World. Why isn't
the Massachussets "Elegant Tern" a Lesser Crested
Tern, as suggested by Martin Reid? I'm inclined to
agree with Martin's identification. Isn't rump
coloration (obviously gray on my monitor) more
diagnostic than something as notoriously variable as
bill coloration?
-Floyd
__________________________________________________
Do You Yahoo!?
Yahoo! Finance - Get real-time stock quotes
http://finance.yahoo.com
[ << | >> | ^^ ]
Subject: Elegant vs Lesser Crested
From: Julian Hough <Jrhough1(AT)AOL.COM>
Date: 22 Aug 2002 9:04am
Identification of orange-billed terns in Europe, and now North America, this
summer is something of a paradox.
Birder's in Europe have been perplexed by individuals in Holland and the UK (see
surfbirds.com for links to photos) which superficially resemble Elegant Terns,
but appear a "little off" in some respects.
An individual in Norfolk, UK, with a striking white rump, was thought to be
either a hybrid 'something', or a Lesser Crested. The white (not grey as in
typical Lesser crested ) rump was explained away by variation, or the fact that
further investigation would show that, contrary to popular belief, some Lesser
Cresteds can have white rumps. As far as I know, the latter has still to be
proven, delaying conclusive identification of these individuals.
Now, we have an Elegant-looking tern in Mass., USA, which appears to be an
Elegant Tern, other than the rump looks grey, when it should be white.
The size of the bird, the longish, not-very-orange bill (reddish with a
yellowish tip), mantle colour and leggy look, combined with the shape and extent
of the black on the head don't impart a Lesser Crested look. Since the bird
looks like an Elegant Tern (to me, at least) rather than a LC , is it not
logical to assume that maybe Elegant Terns can show greyish rumps?
Also, since the Mass. bird is a first-summer and it has been suggested that if
some LC can have white rumps, then isn't it likely that young LC may be the ones
more likely to have whiter rumps? If so, then the Mass bird doesn't fit into
that train of thought since it has a greyish rump.
If observers in CA can comment on variation in rump color, ie. do Elegant Terns
ever show grey rumps?, it may prove helpful in eliminating current confusion.
Julian Hough,
CT, USA
[ << | >> | ^^ ]
Subject: Re: Elegant vs Lesser Crested
From: Alvaro Jaramillo <chucao(AT)ATTBI.COM>
Date: 22 Aug 2002 11:26am
At 11:59 AM 8/22/2002 -0400, Julian Hough wrote:
>If observers in CA can comment on variation in rump color, ie. do Elegant
>Terns ever show grey rumps?, it may prove helpful in eliminating current
>confusion.
Easier said than done. I have been looking at and photographing Elegant
Terns this season, seeing the colour of the rump is super hard to do in the
field. Lighting conditions, distance to the birds, and the fact that
Elegant Terns don't show much of the rump colour when perched makes it
difficult. So getting a good sample of rump colours in the field is going
to be very difficult. I would suggest that answering this question (and
many other bird ID problems) needs a good review of specimen material.
Al
Alvaro Jaramillo
Biologist
San Francisco Bay Bird Observatory
P.O. Box 247
Alviso, CA 95002
(408)-946-6548
http://www.sfbbo.org/
chucao(AT)attbi.com
[ << | >> | ^^ ]
Subject: Juvenile Pine Siskin vs. Lawrence's Goldfinch
From: Ted Floyd <tedfloyd(AT)ABA.ORG>
Date: 22 Aug 2002 12:48pm
Hello, birders.
Ian Paulsen <ipaulsen(AT)KRL.ORG> writes:
> So does anyone have a source for good illustrations of
> juvenile goldfinches/siskin and how to separate them?
You might want to check out Clements' _Finches and Sparrows_
(Princeton, 1993), which shows a juvenile Lawrence's Goldfinch
(Fig. 67e) on pl. 12 and a juvenile Pine Siskin (Fig. 50c)
on pl. 13. There is a brief discussion of the juvenile
Pine Siskin on p. 222 and a somewhat lengthier discussion
of the juvenile Lawrence's Goldfinch on pp. 239-240.
Best,
Ted
----------------------------
Ted Floyd
Editor,
Birding
American Birding Association
P.O. Box 7974
Boulder, Colorado 80306-7974
303-444-6365
tedfloyd(AT)aba.org
[ << | >> | ^^ ]
Subject: Re: Elegant vs Lesser Crested
From: miguel demeulemeester <miguel(AT)DEMEULEMEESTER.NET>
Date: 22 Aug 2002 1:28pm
This is a multi-part message in MIME format.
----INCLUDING text/plain MIME SECTION----
Hi all,
Sorry I'm just inquiring.
Again, sorry, maybe little stupide from me, but what about the bill in
that Massachussets bird? Doesn't the Elegant Tern has little or no
gonycal angle?
In some of the close ups on those pictures, there's a serious angle on
that bill.
Now, I haven't studied to many Elegants here in San Francisco that
close, but as far as I remember from the literature I read (maybe
controversial too ???) they are not supposed to show that. Also, I'd
probably have to read more on them, just inquiring...
And I'll do my effort this weekend to check a bunch in Bolinas for
grey(ish) rumps. If they are going to be as variable as Little Terns
are... then there are tons of Least Terns in Europe and tons of ???
orange-billed Terns on the US west coast.
Of course rump is not the main feature for ID'ing Leasts.
Also, the coloration seems a little odd to me.
Regards, Miguel
San Francisco, USA
originally from Belgium
<-----Original Message----->
>
>From: Julian Hough
>Sent: 8/22/2002 12:03:11 PM
>To: BIRDWG01(AT)listserv.arizona.edu
>Subject: [BIRDWG01] Elegant vs Lesser Crested
>
>Identification of orange-billed terns in Europe, and now North America,
this summer is something of a
>paradox.
>
>Birder's in Europe have been perplexed by individuals in Holland and
the UK (see surfbirds.com for
>links to photos) which superficially resemble Elegant Terns, but appear
a "little off" in some
>respects.
>
>An individual in Norfolk, UK, with a striking white rump, was thought
to be either a hybrid
>'something', or a Lesser Crested. The white (not grey as in typical
Lesser crested ) rump was
>explained away by variation, or the fact that further investigation
would show that, contrary to
>popular belief, some Lesser Cresteds can have white rumps. As far as I
know, the latter has still to
>be proven, delaying conclusive identification of these individuals.
>
>
>Now, we have an Elegant-looking tern in Mass., USA, which appears to be
an Elegant Tern, other than
>the rump looks grey, when it should be white.
>The size of the bird, the longish, not-very-orange bill (reddish with a
yellowish tip), mantle colour
>and leggy look, combined with the shape and extent of the black on the
head don't impart a Lesser
>Crested look. Since the bird looks like an Elegant Tern (to me, at
least) rather than a LC , is it
>not logical to assume that maybe Elegant Terns can show greyish rumps?
>
>
>Also, since the Mass. bird is a first-summer and it has been suggested
that if some LC can have white
>rumps, then isn't it likely that young LC may be the ones more likely
to have whiter rumps? If so,
>then the Mass bird doesn't fit into that train of thought since it has
a greyish rump.
>
>If observers in CA can comment on variation in rump color, ie. do
Elegant Terns ever show grey
>rumps?, it may prove helpful in eliminating current confusion.
>
>Julian Hough,
>CT, USA
>
----DELETED text/html MIME SECTION----
[ << | >> | ^^ ]
Subject: Re: Elegant vs Lesser Crested
From: Richard Heil <rsheil(AT)JUNO.COM>
Date: 22 Aug 2002 5:37pm
On Thu, 22 Aug 2002 11:27:57 -0700 Alvaro Jaramillo <chucao(AT)ATTBI.COM>
writes:
> At 11:59 AM 8/22/2002 -0400, Julian Hough wrote:
So getting a good sample of rump colours in the field is
> going
> to be very difficult. I would suggest that answering this question
> (and
> many other bird ID problems) needs a good review of specimen
> material.
A recent review of specimens of Elegant Terns at Harvard's Museum
of Comparative Zoology by Jeremiah Trimble, at The Slater Museum (U. of
Puget Sound) by Dennis Paulsen, and at the Natural History Museum of Los
Angeles County by Kimball Garrett has, in each collection, revealed that
rump/ upper tail coverts vary from white to quite gray (particularly on
first winter/summer birds).
Rick Heil
S.Peabody,MA rsheil(AT)juno.com
[ << | >> | ^^ ]
Subject: Re: Elegant vs Lesser Crested
From: Glenn A dEntremont <gdentremont(AT)JUNO.COM>
Date: 22 Aug 2002 6:36pm
Well, finally some words of wisdom.
If one would look critically at the flight picture (sorry, I am having
problems tonight getting online with the WWW) which I believe is Flight
#1, then you would see the area which borders the sandflat which
corresponds to the rump area. This picture shows white in this area with
the edge of the left side of the tail grayish. Since I was present
during the taking of these photos, I know that the bird was fanning the
tail and drooping the edges as it gained altitude. This means that the
"gray" area is facing away from the light source and is in shadow in
relation to the rump. It should be grayer than the rump. Can't see the
right side? This is because the tail is drooped-upside down "U" shape if
seen head on. The rump shows white here because it was white. Even the
poor quality long distance shots show whitish in the center of the rump.
Here brings up an technological query. How does digital photography from
long distances handle the gradual white to gray? These areas are so
small could the computer asigning values of gray (which have to be
finite-not like real film) on areas which have a distinct line of
gray/white no matter how gray?
Again, this bird's shape, bill color, size, color of mantle (in relation
to Common) and crest is much more consistant with Elegant than Lesser
Crested. This is why no one who has seen this bird has anything to
comment on the "gray" rump which seems to have most of you hung up.
See my previous post. The skins showed the relationship of size and
mantle color and rump color which was seen of this bird to Common. The
third and fourth from the left were the two that reflected the proper
relationships. Then I looked at the key. How about that-these two are
Elegant.
Several, if not all, of the Massachusetts Avian Rarity Committee have
seen this bird. No one here is questioning the ID. Why some feel that
eye witness accounts are not worthy of acceptance is incomprehensible.
Glenn
On Thu, 22 Aug 2002 11:27:57 -0700 Alvaro Jaramillo <chucao(AT)ATTBI.COM>
writes:
> At 11:59 AM 8/22/2002 -0400, Julian Hough wrote:
>
> >If observers in CA can comment on variation in rump color, ie. do
> Elegant
> >Terns ever show grey rumps?, it may prove helpful in eliminating
> current
> >confusion.
>
> Easier said than done. I have been looking at and photographing
> Elegant
> Terns this season, seeing the colour of the rump is super hard to do
> in the
> field. Lighting conditions, distance to the birds, and the fact that
> Elegant Terns don't show much of the rump colour when perched makes
> it
> difficult. So getting a good sample of rump colours in the field is
> going
> to be very difficult. I would suggest that answering this question
> (and
> many other bird ID problems) needs a good review of specimen
> material.
>
> Al
>
> Alvaro Jaramillo
> Biologist
> San Francisco Bay Bird Observatory
> P.O. Box 247
> Alviso, CA 95002
> (408)-946-6548
> http://www.sfbbo.org/
> chucao(AT)attbi.com
Glenn d'Entremont
gdentremont(AT)juno.com
Stoughton, MA
[ << | >> | ^^ ]
Subject: Re: Elegant vs Lesser Crested
From: Phil Davis <pdavis(AT)IX.NETCOM.COM>
Date: 22 Aug 2002 7:47pm
Glenn -
The operative word is "no one HERE ..." Most of us are not there.
I really don't understand your frustration. This listserver is the
"Frontiers of Bird Identification", not the "Frontiers of Bird Sight
Records". I believe that the science and/or art of bird identification is
(or should be) predicated on written/photographic accounts, whether they
end up as records committee decisions or contributing to a species account
in the next "Terns of the World" monograph. Identification data must be
passed on via detailed written reports supplemented by photos, images,
videos, and recordings. Reports should unequivocally convince a reader of
the correctness of the identification. Simply saying that someone saw a
given species is just not good enough for our contemporaries, not to
mention posterity.
Eyewitness can and do make mistakes ...
Phil
Since this message is verging on being off-topic, it probably does not make
sense to pursue this issue further on this listserver.
At 09:42 PM 08/22/2002 -0400, Glenn A dEntremont wrote:
(snip)
>No one here is questioning the ID. Why some feel that
>eye witness accounts are not worthy of acceptance is incomprehensible.
(snip)
==================================
Phil Davis Davidsonville, Maryland USA
mailto:PDavis(AT)ix.netcom.com
==================================
[ << | >> | ^^ ]
Subject: Re: Elegant vs Lesser Crested
From: Andy Guthrie <andyguthrie(AT)EARTHLINK.NET>
Date: 22 Aug 2002 8:19pm
I took a quick look at measurements of Elegant & Lesser Crested Tern in
Malling & Olsen's "Terns of Europe and North America". The results
surprised me in showing substantial overlap in all characters, as follows:
(I hope this formatting stays!)
LC EL
Wing 280-324mm 300-328
Tail Fork 55-83 35-85
Bill 47.2-62.0 53.2-68.6
Bill depth
at Gonys 8.3-10.9 8.6-10.9
at Nostrils 10.1-13.3 10.2-13.0
Tarsus 23.0-29.0 25.5-32.2
Caveat: All measurements are for adults. Malling & Olsen have some
measurements for 2nd winter/summer Lesser Crested Terns (e.g., bill length
47.9-56.4) but not for Elegant.
Regarding the specimen studies mentioned in Rick Heil's message below - are
there any photos available that would show the range of variation at
different ages? Are numbers of gray-rumped vs. white-rumped individuals
available? This information may help clarify what appears to be an
important addition to the common wisdom of separating these two terns. For
example, quoting from Malling & Olsen on page 63: "Elegant Tern is
reminiscent of Lesser Crested Tern, but has a longer bill and crest, and the
pale grey upperparts contrast with white rump and tail - the most important
character compared with Lesser Crested."
In light of the new information mentioned below, this may need to be
revisited!
----- Original Message -----
From: "Richard Heil" <rsheil(AT)JUNO.COM>
To: <BIRDWG01(AT)listserv.arizona.edu>
Sent: Thursday, August 22, 2002 8:33 PM
Subject: Re: [BIRDWG01] Elegant vs Lesser Crested
> On Thu, 22 Aug 2002 11:27:57 -0700 Alvaro Jaramillo <chucao(AT)ATTBI.COM>
> writes:
> > At 11:59 AM 8/22/2002 -0400, Julian Hough wrote:
>
> So getting a good sample of rump colours in the field is
> > going
> > to be very difficult. I would suggest that answering this question
> > (and
> > many other bird ID problems) needs a good review of specimen
> > material.
>
> A recent review of specimens of Elegant Terns at Harvard's Museum
> of Comparative Zoology by Jeremiah Trimble, at The Slater Museum (U. of
> Puget Sound) by Dennis Paulsen, and at the Natural History Museum of Los
> Angeles County by Kimball Garrett has, in each collection, revealed that
> rump/ upper tail coverts vary from white to quite gray (particularly on
> first winter/summer birds).
>
>
> Rick Heil
> S.Peabody,MA rsheil(AT)juno.com
[ << | >> | ^^ ]
Subject: Re: Elegant vs Lesser Crested
From: Don Crockett <crockett(AT)GREATBLUE.COM>
Date: 22 Aug 2002 9:04pm
I shot the video in question:
http://www.virtualbirder.com/vbirder/rba/elte
and I don't believe that the apparent gray rump in some of
the stills is just an artifact of the digital capture.
The following image:
http://www.virtualbirder.com/vbirder/rba/elte/elte11.jpg (Flight 5)
shows a rump of the same color as the mantle while showing
whiter surrounding feathers which are on the same plane
relative to the light source. I don't believe that can be
explained as a digital or optical artifact.
If you look at:
http://www.virtualbirder.com/vbirder/rba/elte/elte2.jpg (Flight 2)
it also seems to show a gray rump and whiter tail feathers.
I wouldn't deny that people observed a white rump. Looking at
some of the video, the rump, or what appears to be the rump,
does look white (this shot is a little blurry):
http://www.virtualbirder.com/vbirder/rba/elte/elte13.jpg (Flight 4)
Certain stills from the side, when the bird was on the ground,
could more likely lead one to call the rump white.
However, given the total video footage I shot, I would say that
the rump was gray.
Rick Heil indicates that an Elegant Tern specimen review shows
that rump color is not a reliable mark especially on birds of
this age. So...
As far as bill color and mantle shade comparisons, I wouldn't
trust my video stills.
Don
Glenn d'Entremont wrote:
>Well, finally some words of wisdom.
>
>If one would look critically at the flight picture (sorry, I am having
>problems tonight getting online with the WWW) which I believe is Flight
>#1, then you would see the area which borders the sandflat which
>corresponds to the rump area. This picture shows white in this area with
>the edge of the left side of the tail grayish. Since I was present
>during the taking of these photos, I know that the bird was fanning the
>tail and drooping the edges as it gained altitude. This means that the
>"gray" area is facing away from the light source and is in shadow in
>relation to the rump. It should be grayer than the rump. Can't see the
>right side? This is because the tail is drooped-upside down "U" shape if
>seen head on. The rump shows white here because it was white. Even the
>poor quality long distance shots show whitish in the center of the rump.
>
>Here brings up an technological query. How does digital photography from
>long distances handle the gradual white to gray? These areas are so
>small could the computer asigning values of gray (which have to be
>finite-not like real film) on areas which have a distinct line of
>gray/white no matter how gray?
>
>Again, this bird's shape, bill color, size, color of mantle (in relation
>to Common) and crest is much more consistant with Elegant than Lesser
>Crested. This is why no one who has seen this bird has anything to
>comment on the "gray" rump which seems to have most of you hung up.
>
>See my previous post. The skins showed the relationship of size and
>mantle color and rump color which was seen of this bird to Common. The
>third and fourth from the left were the two that reflected the proper
>relationships. Then I looked at the key. How about that-these two are
>Elegant.
>
>Several, if not all, of the Massachusetts Avian Rarity Committee have
>seen this bird. No one here is questioning the ID. Why some feel that
>eye witness accounts are not worthy of acceptance is incomprehensible.
>
> Glenn
>
>On Thu, 22 Aug 2002 11:27:57 -0700 Alvaro Jaramillo <chucao(AT)ATTBI.COM>
>writes:
>> At 11:59 AM 8/22/2002 -0400, Julian Hough wrote:
>>
>> >If observers in CA can comment on variation in rump color, ie. do
>> Elegant
>> >Terns ever show grey rumps?, it may prove helpful in eliminating
>> current
>> >confusion.
>>
>> Easier said than done. I have been looking at and photographing
>> Elegant
>> Terns this season, seeing the colour of the rump is super hard to do
>> in the
> > field. Lighting conditions, distance to the birds, and the fact that
>> Elegant Terns don't show much of the rump colour when perched makes
>> it
>> difficult. So getting a good sample of rump colours in the field is
>> going
>> to be very difficult. I would suggest that answering this question
>> (and
>> many other bird ID problems) needs a good review of specimen
>> material.
>>
>> Al
>>
>> Alvaro Jaramillo
>> Biologist
>> San Francisco Bay Bird Observatory
>> P.O. Box 247
>> Alviso, CA 95002
>> (408)-946-6548
>> http://www.sfbbo.org/
>> chucao(AT)attbi.com
>
>Glenn d'Entremont
>gdentremont(AT)juno.com
>Stoughton, MA
--
Don Crockett - mailto:crockett(AT)greatblue.com
The Virtual Birder(R) - http://www.virtualbirder.com
A2Z4Birders Guide to Birds(sm) - http://www.a2z4birders.com/birds
Brookline, Massachusetts
[ << | >> | ^^ ]
Subject: Re: Elegant vs Lesser Crested
From: Don Crockett <crockett(AT)GREATBLUE.COM>
Date: 22 Aug 2002 9:23pm
I previously wrote:
>As far as bill color and mantle shade comparisons, I wouldn't
>trust my video stills.
Let me clarify this comment.
As far as the mantle shade comparison, I was mainly referring to
the variability of mantle shade in a single image based on the
lighting angle. Need to be careful in comparing.
However, If you look at:
http://www.virtualbirder.com/vbirder/rba/elte/elte13.jpg (Flight 4)
I would say that given the birds positions, the image does accurately
depict a lighter mantle on the subject bird than the surrounding
Common Terns. But you do have to be careful :) .
As far as color, it is notoriously tricky on computer displays
due to variations in color profiles and calibrations between
computers.
Don
--
Don Crockett - mailto:crockett(AT)greatblue.com
The Virtual Birder(R) - http://www.virtualbirder.com
A2Z4Birders Guide to Birds(sm) - http://www.a2z4birders.com/birds
Brookline, Massachusetts
[ << | >> | ^^ ]
Subject: Re: Elegant vs Lesser Crested
From: Don Roberson <creagrus(AT)MONTEREYBAY.COM>
Date: 23 Aug 2002 8:14am
For reference purposes, I have posted three shots from my collection that show
Elegant Terns in flight and that show rump color. Each is a different plumage
although the "first-basic" might be a second-summer (=adult) although I think
there is a trace of covert bar. Each shot is unretouched. The three shots
obviously do not show the range of variation, and each shows a white rump, but
there is apparent variation in the contrast from the mantle age-to-age.
The page is at http://montereybay.com/creagrus/ELTEflyrump.html
Don Roberson
Pacific Grove CA
[ << | >> | ^^ ]
Subject: Digital photos and bird ID (off topic & long)
From: Matt Sharp <sharp(AT)ACNATSCI.ORG>
Date: 23 Aug 2002 8:24am
Hello
I will preface this with an apology for an off-topic post
but I simply cannot resist the opportunity to rant a bit.
I have been receiving a lot of digital images for North
American Birds and many of them are jpgs. I think the
situation with MA Elegant Tern is a good example of the
fact that (and I will put this in bold to emphasize the point)
JPGS ARE NOT AN APPROPRIATE MEDIUM FOR DISPLAYING
AND DISCUSSING THE FINE POINTS OF BIRD ID.
ESPECIALLY when jpgs are displayed on computer screens.
jpgs are designed to compress image data so that it can
be quickly and pleasingly displayed on a computer screen
and so it can be easily transmitted via the internet.
IT IS NOT DESIGNED TO ACCURATELY REPRESENT WHAT
SOMETHING LOOKED LIKE IN REALITY.
It is a highly compressed format and depending on how the
files are saved can lose most of the subtle changes in tone
and color, and edge detail. You can control how compressed
jpgs are when you save them and supposedly the format
can achieve a compression ratio up to 20:1 without visible
loss of image quality but this will depend on how much
image data there is to begin with. In photos where the
subject is small in the frame, lacking in strong contrast, and not
tack sharp, I imagine even low compression levels will still lose
subtle details. More info on jpgs is available on the web. One
very concise explanation can be found at
http://www.faqs.org/faqs/jpeg-faq/
The main point though is that without a detailed
analysis of the image file in comparison to the physical reality
that the image is supposed to represent there is NO WAY TO
KNOW OR MEASURE HOW MUCH DETAIL HAS BEEN LOST. So
often these discussions based on images of unknown format
displayed on various computer screens drive me nuts, because
there is simply no objective standard available to determine what
is accurately represented in an image and what is due to file
compression, vagaries of the light when the image is captured
on CCD, etc.
This is common knowledge but it should always be kept in
mind when assessing any image.
A: There is NO technology that is equivalent to the human retina
when it comes to assessing subtle tonal, and color gradations and
detail.
B: There is NO technology widely available that is equivalent to
FILM in terms of capturing detail, and subtle tonal and color gradation.
(There is a new chip rumored to close this gap but it is not yet available
to the average consumer)
C: jpgs, and other file formats designed for use on the web (giff, bmp
etc) are the WORST at accurately displaying subtle tonal and color
gradations.
The main source of my frustration comes from the fact that
while jpgs are potentially misleading on a computer screen
they are even worse in print, especially at low resolution.
The other side of this coin is that 80-90% of the time they
are adequate to accurately represent what a bird looked like in
the field, and they are the easiest way to send images via
the internet, and to display them via the web (that is after all
what they were designed to do). So there is a conflict involved
between convenience and accuracy. In some cases the convenience
of jpgs leads to confusion over what a bird may have really looked
like because a jpg is an inaccurate representation.
I realize that there are probably plenty of people on this list
who know this stuff better than I ( I am no tech junkie) and
I am still in the process of learning many of these details so
perhaps my frustration is a bit fresher than some.
It is also worth pointing out that while some of the specific
issues here may not have been "real" they have led to an
interesting discussion of the fine points of crested tern ID
which has been very informative even if unnecessarily heated.
With the growing popularity of digiscoping the limitations of
the jpg file format need to be kept in mind when submitting
digital images of vagrants and when discussing IDs based on
those images.
Respectfully
Matt Sharp
Collection Manager
VIREO/ANS
1900 Benjamin Franklin Pkwy.
Philadelphia PA 19103
www.acnatsci.org/vireo
(tel.) 215-299-1069
(fax) 215-299-1182
[ << | >> | ^^ ]
Subject: Re: Elegant vs Lesser Crested
From: Tony Leukering <GreatGrayO(AT)AOL.COM>
Date: 23 Aug 2002 8:45am
----INCLUDING text/plain MIME SECTION----
Hi all:
The discussion of this beast is entering new waters - perhaps it should be
moved to the Records Committee listserver.
Though I do not know Glenn d'Entremont, I completely understand his
frustration, as the bird has been described and the rump was described as
being white. Therefore, that is the written description submitted. I would
trust such a description much more than I would trust something as
notoriously unreliable as monitor interpretations of color. I consider it
irrelevant that, perhaps, the rump might actually have been gray (see Don
Crockett's post), the important facet of this aspect of this part of the
discussion on the MA ELTE is the apparent complete acceptance of minor shade
diffferences in color that individuals detect on their monitors as gospel
truth when the observers describe the bird differently.
This discussion reminds me of the one a few years back about the Northern
Parula picture from Colorado in North American Birds (probably Field Notes at
the time). Everyone saw this whacking obvious white superciliary in the
picture and jumped to the conclusion that the bird had to be a hybrid. Of
course, the picture presented was a black-and-white rendition of a color
slide that was scanned and the contrast on the head pattern got bumped up
astronomically.
The take-home message: Trust what good people tell you they saw,
particularly when all the shape and structure features (that are much more
reliable on our monitors than are subtle color shades) support the
identification as presented.
Respectfully,
Tony Leukering
Brighton, CO
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[ << | >> | ^^ ]
Subject: Re: Digital photos and bird ID (off topic & long)
From: Joseph Morlan <jmorlan(AT)CCSF.ORG>
Date: 23 Aug 2002 9:31am
On Fri, 23 Aug 2002 11:22:42 -0400, Matt Sharp <sharp(AT)ACNATSCI.ORG>
wrote:
>A: There is NO technology that is equivalent to the human retina
>when it comes to assessing subtle tonal, and color gradations and
>detail.
Perhaps. But it is routine for different observers to describe the
same bird differently, sometimes using widely different terminology.
I have a modest test that I use it class. It is a pretty good slide
of a Flesh-footed Shearwater. When polled, half the class will say
the bill is yellow. The other half will say the bill is pink. In my
view the bill is clearly pink; and pink and yellow have nothing in
common. Yet every time I conduct this test, about half the students
will insist the bill is yellow. What is a records committee to make
of such descriptions when we are all seeing exactly the same image?
Furthermore light conditions will change what observers see. Apparent
mantle color on gulls and terns will change on the same bird when the
angle changes. And, yes, I have seen pale gray described as white by
experienced observers. I have probably done so myself.
Worse, the human brain is not a camera. Different witnesses to any
event will remember things differently. The retina may not lie, but
human beings are notorious for seeing things differently from the way
they are.
>B: There is NO technology widely available that is equivalent to
>FILM in terms of capturing detail, and subtle tonal and color gradation.
>(There is a new chip rumored to close this gap but it is not yet available
>to the average consumer)
It depends on the film, the lighting conditions, etc. If I had a
nickel for every time an observer claimed the pictures don't look like
the bird, I'd be rich. Much bird photography uses high speed film
which biases color balance.
>C: jpgs, and other file formats designed for use on the web (giff, bmp
>etc) are the WORST at accurately displaying subtle tonal and color
>gradations.
In my experience, with adjustments to color balance and exposure,
jpegs can often come very close to approximating the original film.
However, that's just on my monitor. Other people have their monitors
adjusted differently and therein lies a significant problem. I agree.
--
Joseph Morlan, Pacifica, CA 94044: mailto:jmorlan(AT)ccsf.org
Fall Birding Classes start Sept 4: http://fog.ccsf.org/~jmorlan/
California Bird Records Committee: http://www.wfo-cbrc.org/cbrc/
[ << | >> | ^^ ]
Subject: Re: Elegant vs Lesser Crested
From: Clay Taylor <CTaylor(AT)WORLDNET.ATT.NET>
Date: 23 Aug 2002 11:47am
All -
Glenn brings up the crux of the matter when dealing with any digital
field ID photos - the dynamic range of the camera (the number of gray tones
that can be reproduced, with "white" and "black" as the starting and ending
points of the gray scale). The popular point-and-shoot digitals like the
Nikon CoolPix series have very impressive resolution (that's the
megapixels), but the expensive interchangeable-lens SLR bodies like a Nikon
D1 have tons more dynamic range. I gather that the set of photos from Don
Crockett were taken from his video camera, so the amount of available pixels
and the dynamic range of the processor are big unknowns.
Another problem that we all must understand is color fidelity,
especially when dealing with an image on a computer screen. If you go to
www.dpreview.com and read their in-dapth digital camera reviews, they give
you a hint as to how critical it is to make sure that your monitor is
correctly adjusted when you are trying to evaluate fine nuances in a photo.
Also, unless the photographer had set his digital camera / camcorder to a
specific "white balance" before taking the photos in question (typically
using a calibrated white card or gray card), it may be operating on "Auto
White Balance", which means the processor looks at the overall range of
colors in the entire picture area and "decides" what is an appropriate color
balance. Even the cameras (like mine) that give you choices between
"sunny" and "shade" cannot possibly give consistent results over the course
of a day, as the color temperature of the sunlight changes from morning to
afternoon light.
I have done digiscope head-shots of a gull at high magnification, so the
white of its head and breast are influencing both the exposure and color
balance of the shot, but when I zoom back on the framing, BOTH exposure and
color balance are changed merely by adding a lot of mudflat into the
composition.
I'm not saying that Don's or anyone else's shots are useless, but I do
not believe that any single frame should be relied on to as the ultimate
arbiter of "gray rump vs. white rump", "orange bill vs. yellow bill", etc.
I went out to South Beach yesterday, but did not see the Elegant Tern
(rats!).
Clay Taylor
Moodus, CT
ctaylor(AT)att.net
----- Original Message -----
From: "Glenn A dEntremont" <gdentremont(AT)JUNO.COM>
To: <BIRDWG01(AT)listserv.arizona.edu>
Sent: Thursday, August 22, 2002 9:42 PM
Subject: Re: [BIRDWG01] Elegant vs Lesser Crested
> Well, finally some words of wisdom.
>
> If one would look critically at the flight picture (sorry, I am having
> problems tonight getting online with the WWW) which I believe is Flight
> #1, then you would see the area which borders the sandflat which
> corresponds to the rump area. This picture shows white in this area with
> the edge of the left side of the tail grayish. Since I was present
> during the taking of these photos, I know that the bird was fanning the
> tail and drooping the edges as it gained altitude. This means that the
> "gray" area is facing away from the light source and is in shadow in
> relation to the rump. It should be grayer than the rump. Can't see the
> right side? This is because the tail is drooped-upside down "U" shape if
> seen head on. The rump shows white here because it was white. Even the
> poor quality long distance shots show whitish in the center of the rump.
>
> Here brings up an technological query. How does digital photography from
> long distances handle the gradual white to gray? These areas are so
> small could the computer asigning values of gray (which have to be
> finite-not like real film) on areas which have a distinct line of
> gray/white no matter how gray?
>
> Again, this bird's shape, bill color, size, color of mantle (in relation
> to Common) and crest is much more consistant with Elegant than Lesser
> Crested. This is why no one who has seen this bird has anything to
> comment on the "gray" rump which seems to have most of you hung up.
>
> See my previous post. The skins showed the relationship of size and
> mantle color and rump color which was seen of this bird to Common. The
> third and fourth from the left were the two that reflected the proper
> relationships. Then I looked at the key. How about that-these two are
> Elegant.
>
> Several, if not all, of the Massachusetts Avian Rarity Committee have
> seen this bird. No one here is questioning the ID. Why some feel that
> eye witness accounts are not worthy of acceptance is incomprehensible.
>
> Glenn
>
> On Thu, 22 Aug 2002 11:27:57 -0700 Alvaro Jaramillo <chucao(AT)ATTBI.COM>
> writes:
> > At 11:59 AM 8/22/2002 -0400, Julian Hough wrote:
> >
> > >If observers in CA can comment on variation in rump color, ie. do
> > Elegant
> > >Terns ever show grey rumps?, it may prove helpful in eliminating
> > current
> > >confusion.
> >
> > Easier said than done. I have been looking at and photographing
> > Elegant
> > Terns this season, seeing the colour of the rump is super hard to do
> > in the
> > field. Lighting conditions, distance to the birds, and the fact that
> > Elegant Terns don't show much of the rump colour when perched makes
> > it
> > difficult. So getting a good sample of rump colours in the field is
> > going
> > to be very difficult. I would suggest that answering this question
> > (and
> > many other bird ID problems) needs a good review of specimen
> > material.
> >
> > Al
> >
> > Alvaro Jaramillo
> > Biologist
> > San Francisco Bay Bird Observatory
> > P.O. Box 247
> > Alviso, CA 95002
> > (408)-946-6548
> > http://www.sfbbo.org/
> > chucao(AT)attbi.com
>
> Glenn d'Entremont
> gdentremont(AT)juno.com
> Stoughton, MA
[ << | >> | ^^ ]
Subject: Re: Digital photos and bird ID (off topic & long)
From: Phil Jeffrey <phil(AT)XRAY2.MSKCC.ORG>
Date: 23 Aug 2002 1:11pm
On Fri, 23 Aug 2002, Matt Sharp wrote:
> JPGS ARE NOT AN APPROPRIATE MEDIUM FOR DISPLAYING
> AND DISCUSSING THE FINE POINTS OF BIRD ID.
Nonsense. Web display has it's issues, but so does every other medium.
> IT IS NOT DESIGNED TO ACCURATELY REPRESENT WHAT
> SOMETHING LOOKED LIKE IN REALITY.
By the same token, neither is film.
The Image->Film->Print route is as beset by artifacts as the
Image->Film->JPG route. In many instances, JPGs of slide images displayed
on monitors are truer to the original slide than any printed
representation based on many photographers experience.
> B: There is NO technology widely available that is equivalent to
> FILM in terms of capturing detail, and subtle tonal and color gradation.
Every recording medium and every representation medium have issues. Some
of them have severe issues. How many of VIREO's images are recorded on
Velvia film ? Velvia has dramatic distortions of color space and
saturation space.
The largest problems in web representation are the host hardware (your
monitor) and software (especially the gamma correction). Both are
notorious in shifting color representations. This does not render them
useless. This renders them as flawed as (say) the print medium. Should
we discard the latter as well ?
Phil Jeffrey
NYC
[ << | >> | ^^ ]
Subject: Re: Elegant vs Lesser Crested
From: Don Crockett <crockett(AT)GREATBLUE.COM>
Date: 23 Aug 2002 2:48pm
Sorry to keep beating this horse...
The video was shot with a Canon XL1, miniDV, 3 chips, .25MPixels/chip,
dynamic range well below that of a Nikon CoolPix. I had the camera
on manual settings with an exposure of around F8.0 and a shutter
speed between 1/600th and 1/1000th of a second. I had the exposure
set to slightly underexpose the white of the gulls to try to avoid
any clipping.
In evaluating the images I do not make any claims of how accurate
any one color is to reality. The best I can do is to compare neighboring
colors in the same image (or neighboring images in the video sequence)
and make relative assessments based on the represented pixels and the
interpretation of the geometry of the bird relative to the light
source
and the camera. In the sharpest images, with the bird banking into the
camera, providing the most consistent and clearest view of the surface
across the back and tail, images Flight 4 & 5 show a rump whose color
is similar to the gray of the mantle, darker than the surrounding edges
of the rump and the tail. It is the consistency of the color of mantle
and rump that are the most compelling since the geometry of the mantle
is the most similar to the rump. Clipping can not account for this effect.
Given there are white edges and white tail feathers, underexposure
can not account for this effect either. These shots were distant so I
am not as confident with them as I might be if they were closer (a small
number of pixels represent these areas). This appearance however does show
up in multiple sequences. And if you look at the Common Terns in Flight 3
in similar flight positions and distances you can clearly see that they
do have white rumps as you would expect.
You do have to take into account the limitations of the technology
used in creating an image. But just because a technology is
limited does not mean that you can not extract useful information
from it.
Don
Images referred to above appear on:
http://www.virtualbirder.com/vbirder/rba/elte
> Glenn brings up the crux of the matter when dealing with any digital
>field ID photos - the dynamic range of the camera (the number of gray tones
>that can be reproduced, with "white" and "black" as the starting and ending
>points of the gray scale). The popular point-and-shoot digitals like the
>Nikon CoolPix series have very impressive resolution (that's the
>megapixels), but the expensive interchangeable-lens SLR bodies like a Nikon
>D1 have tons more dynamic range. I gather that the set of photos from Don
>Crockett were taken from his video camera, so the amount of available pixels
>and the dynamic range of the processor are big unknowns.
--
Don Crockett - mailto:crockett(AT)greatblue.com
The Virtual Birder(R) - http://www.virtualbirder.com
A2Z4Birders Guide to Birds(sm) - http://www.a2z4birders.com/birds
Brookline, Massachusetts
[ << | >> | ^^ ]
Subject: Image quality in jpegs
From: John Idzikowski <idzikoj(AT)UWM.EDU>
Date: 23 Aug 2002 11:04pm
The recent discussion suggested that the compression of jpegs may
compromise detail needed for proper plumage studies and identification. For
those who edit raw jpeg images for web presentation, whether from
digiscoping, digibinoxing, digital video capture or from our old 35 mm
lenses on digital bodies the initial files we work with initially in our
graphic editing software vary in size and all are too large for the Net
because of size. My "raw" originals are usually 1280 x 960 @ 250 kb, but
many can be larger. During the editing process I attempt to edit for
brightness and contrast as there often seems to be a brightness loss as part
of the digital imaging process; I see this unedited darkening all the time
on posted bird shots (brightening my monitor does not help). I never edit
for color balance and saturation as this is far more dangerous to the
integrity of the evidence for accurate presentation. As graphics editor
software compress differently, i.e. a compression ratio in one may result in
a different file size than the same ratio in another program, perhaps this
issue of quality and compression can be addressed by using an image with a
standard pixel size of say 500 X 600 and then vary image file size of the
same image as a function of compression while retaining the original pixel
dimensions. As one's monitor screen resolution remains the same perhaps we
can view a threshold of significant quality loss based on file size. I have
done this in an album entitled "jpeg compression" at
http://community.webshots.com/user/idzikoj
The slight graininess of the shots is due to a high ASA setting used to
capture the motion of the bird. The first 2 images are crops of the head
without compression from 290 kb and 124 kb originals like nos. 3 through 8
(the album will not allow posting of such large images) and then uncropped
images are stepped down to 11 kb for your analysis. Are the grays affected?
We might take each image and enlarge it to see if any color detail is
present on the eyering or gape and at what file size is that lost if it is
at all. I see jpegs over-compressed to the point of degradation, especially
on personal websites and albums all the time; this obvious below acceptable
minimum threshold appears as blurriness and smudging around the edges of
objects where there is contrast.
This is the third time using a different image that I have done this
exercise and each time the file size threshold for initial serious
degradation of roughly a 500 X 600 pixel image is essentially the same.
Perhaps this can be used to find that minimum file size for web publishing
that will result in good quality with quick loading. Maybe before examining
a posted jpeg for ID features we should right click on the image and look at
a file's size properties for a given dimension. A standard of file size and
dimension could be easily established. Needless to say, a higher quality
camera might yield better quality jpegs than another at a smaller file size.
File sizes to be submitted for printing from jpegs is an entirely different
matter. Two editors I recently dealt with requested the largest file size I
had available; this is usually about 150 kb; I have yet to have any feedback
from the printers or the editors; perhaps I will discover that I should be
storing at the full raw sizes.
John Idzikowski, Milwaukee
[ << | >> | ^^ ]
Subject: Elegant Tern specimens at MCZ
From: Blair Nikula <odenews(AT)ATTBI.COM>
Date: 24 Aug 2002 5:26pm
Jeremiah Trimble asked me to post the following message (as he's on his
way to the Aleutians - poor guy!)
Blair Nikula
--
2 Gilbert Lane
Harwich Port, MA 02646
mailto:odenews(AT)attbi.com
web site: http://www.odenews.net/
Dear all,
I wanted to briefly comment on the current discussion of the MA Elegant
Tern, especially referring to rump, upper tail color and gonydeal
angles. I have been able to look at more than 90 specimens of Elegant
Tern which we have here at the MCZ. Of those birds only two are in a
similar non-breeding/1st summer plumage. The rest are in alternate
plumage. Regarding the two non-breeding specimens: Both of these birds
show gray on the rump and tail to different degrees. One of the
specimens shows gray on the upper tail and rump that does not contrast
with the mantle at all. The other specimen has a somewhat lighter gray
tone to the rump and tail and contrasts slightly with the mantle. Both
birds show darker gray on the outer tail feathers. One further comment
can be made after examining the breeding plumaged specimens. Those
specimens which were collected earlier in the season (around March),
showing varying degrees of gray in the tail, while none from May through
July show gray (they are pure white). Of the people from the west coast
I have corresponded with, none have been surprised at seeing gray on the
rump of an Elegant Tern. Specimens which these researchers have
examined have also shown varying amounts of gray on the upper tail and
rump in non-breeding plumage. So, the fact that the MA Elegant Tern
shows gray in the tail and rump should not be disturbing. In fact, from
what I can gather, it may be typical of winter Elegant Terns (winter
adult or first year (12-14 months)) to show gray in the rump and tail.
Concerning the field observations of this bird: I spent at least 2
hours watching this bird. I was able to observe it preening its wings
and even tail and saw it fly at least 4 times. This is what I observed
of the rump and tail: The most obvious feature of the tail was the dark
gray of the outer few tail feathers, especially the tips. The gray on
the tips of the tail feathers decreased on the inner feathers, such that
the inner feathers had no dark gray tip or it was not discernible.
These dark gray tips and outer tail feathers contrasted significantly
with the rest of the tail. Of course in field observations, the
contrast is the most obvious thing and it is often difficult to
determine what the actual color difference is. Having read of the
reported importance of rump and tail color I paid special attention to
this. To my eye, the tail, besides the dark gray already mentioned, was
mostly shaded a very pale gray. In certain light, this appeared pale
gray and in certain lights appeared white. The two central tail
feathers in the field appeared white to me in all lights (except perhaps
the tips), contrasting with the rest of the tail. The rump was more
difficult to get looks at. Yet during the flight views and the few
occasions when it stretched its wings or when it was preening its tail,
the rump appeared very light and certainly contrasted with the pale gray
mantle. It appeared to be the same color as the pale gray tail. In
certain lights appearing pure white and in others pale gray.
I have spent a lot of time looking at bill shape, especially gonydeal
angles, on specimens housed at the MCZ. I can comment briefly on this
as well. Certainly, Elegant Terns do have a gonydeal angle. The MA
Elegant Tern did show a gonydeal angle. This was difficult to see in
the field except at short distances. As we all know, bill shape and
gonydeal angle can appear to change depending on the angle to the
photographer/observer. However, when seen in profile the gonydeal angle
was slight. One comment in the field was an angle of "178 degrees".
The gonydeal angle of the MA bird is very consistent with that shown by
all the specimens I have examined. I will try to have a photograph
posted to Blair Nikula's website illustrating the gonydeal angle and
overall bill shape in a couple of specimens.
I hope this helps.
Sincerely,
Jeremiah Trimble
--
********************************************
Jeremiah Trimble
Curatorial Assistant - Bird Department
Museum of Comparative Zoology
Harvard University
26 Oxford Street
Cambridge, MA 02138
phone: 617-495-2471
fax: 617-495-5667
email: jtrimble(AT)oeb.harvard.edu
********************************************
[ << | >> | ^^ ]
Subject: Re: Elegant vs Lesser Crested - long
From: Martin Reid <upupa(AT)AIRMAIL.NET>
Date: 24 Aug 2002 6:36pm
Dear All,
With the exciting revelation by Richard Heil about ELTE rump colour (more
later), much of the subsequent discussion may be moot - but I would agree
with Don Crockett that in one of his images where COTES are in flight,
those that are closest to the same angle to the camera as is the OB Tern
have obvious white rumps (this means up to where the wings end, not just
the uppertail coverts) with clean demarcation, unlike the OB Tern which has
a smoothly even gray from the back through the rump - with slight paling on
some lateral uppertail coverts and whitish outer retrices.
I have prepared more than a thousand photo images from all kinds of
originals (including video stills) for display as .jpg files on monitors,
and the only way that these images cannot be a fairly close representation
of reality is if the image was selectively edited to achieve this. So
unless Don went to the trouble of deceiving us by doing a great piece of
selective editing on all the images that show the rump, I still feel that
the images indicate that the rump was not cleanly "white and demarcated
from the gray back", as "expected" for ELTE. I'll go further and say that
from my experience, while it is extremely common for white elements in an
image to become exaggerated in the original-to-.jpg process - especially on
small, magnified images - it is virtually impossible to REDUCE white areas
in this process (except deliberately); does this fit with the experience of
others? Thus, I am more inclined to think that the images are showing MORE
white/paleness than in reality, rather than less.
BTW monitor size greatly affects the relative darkness and contrast of an
image:- I create on a 17" monitor (that value is the diagonal size), and
always try to get the color balance and contrast to match the original (and
not using selective editing for any Id-related image) by doing a visual
comparison. However, when that image is viewed on a smaller monitor, it
will be darker and with poor contrast, while when viewed on a larger
monitor, it will appear overexposed and pasty, with poor color depth (I
recommend webmasters to state the creation monitor size, so users can allow
for this).
I agree with Joe Morlan's post about the relative reliability of eyewitness
reports. I have assessed records on an RBC for five years, and from this
and from personal experience, I feel it can be extremely difficult to be
sure of certain bird features of a live moving bird. If the rump on this
bird was only seen by the observers when the tern was in flight ( i.e. not
studied at length while preening), I'd say that it would be very difficult
to be CERTAIN of its color - in that situation, I personally would describe
what I thought I saw, but if someone got good multiple pics of the rump,
I'd trust these more than my notes. Another classic example of this
situation is the black in the primaries of gulls in flight; I have often
thought one thing in the field only to see the photos and realize that I'd
got it wrong (that's why I carry a camera almost everywhere)....
I recall a record of a rarity seen on a pelagic by about 8 observers; one
got photos and submitted them but they were never seen by the other
observers. The photos showed the bird to be a similar but different, even
rarer species (that one observer had suspected all along), but all the
field notes described the less-rare species! after much soul-searching,
most observers felt that they may have ended-up seeing what they should
have because the bird was called-out as that (wrong) species by an
experienced birder.
If there is an experienced birder out there who has NEVER subsequently
realized that a crucial element of their in-the-field description end-up
wrong, please speak up - I want to salute perfection!
I don't know much about ELTEs from personal experience, but the Mass bird
is not an adult, and based on my experience with ROTEs, imms are normally
one shade paler gray than adults. The specimens in that photo that are
being compared are all adults, so it is not a valid comparison, I feel.
But never mind all this, because the REAL news is that from Richard, which
seems to offer a brand new piece of ID info for us all, and at the same
time clear up the rump discrepancy.
This bird looks more like a gray-rumped ELTE than a bright-billed
LCTE, but prior to Richard's email, it seemed - from all available
literature and public statements - that the gray rump was THE most
important ID feature - hence my previous leaning towards LCTE for this
bird, despite some minor discrepancies.
So I follow others in asking Richard/Jeremiah/Dennis/Kimball with great
keenness for more details about gray-rumped ELTEs:- has this data been
published anywhere (or is it in lit.)? are there any photos of these
gray-rumped specimens with collection data?. I feel that the formal
publication of this information is much-anticipated by all who are trying
to identify orange-billed terns (although I feel that Id-ing a LCTE just
got much harder...)
Cheers,
Martin
Martin Reid
Fort Worth, Texas
upupa(AT)airmail.net
http://www.martinreid.com
[ << | >> | ^^ ]
Subject: Elegant Tern - yet again!
From: Blair Nikula <odenews(AT)ATTBI.COM>
Date: 24 Aug 2002 6:43pm
Greetings all,
At the risk of belaboring the issue, I would like to offer a few
additional (and I hope, dispassionate) thoughts on the Massachusetts
"Elegant" Tern (which, unfortunately, has not been seen since 18
August). I want to emphasize at the outset that I have little
experience with Elegant Tern and none with Lesser Crested. However, I
do have a lifetime of experience misidentifying birds and know very well
how apparent field marks can appear, disappear, or change with a simple
and subtle change of angle/light or a slight ruffling of feathers. I
also know well that my mind is at least as capable of playing tricks on
me as is my camera.
To me, the most troubling aspect of the Massachusetts tern is not that
the identity of the bird has been questioned, but that features that
seemed quite clear to me (and others) in the field (based upon at least
two hours observing the bird over two different days) appear, at least
in some cases, to be contradicted by the digital images obtained. I'm
at a loss to explain this, and certainly find it disturbing. I don't
think it can be dismissed simply as a limitation of digital technology,
despite the appeal of that explanation. Digital artifacts may well
affect how shades of gray appear in an image, but it is hard to imagine
that the gray mantle (or white rump) of one tern could be affected while
another tern right beside it in the same light remains unaffected.
Uncertainty over the identity of the Massachusetts tern seems to revolve
around three characteristics: rump color, mantle color, and bill shape
(particularly the gonydeal angle). Indeed, uncertainty over the latter
two features initially led me to report the bird as a "mystery" tern of
the Royal/Elegant ilk. Following are my impression of these features.
Rump color: In the field (under a bright mid-day sun) the rump appeared
white, contrasting with the gray mantle. However, I will confess that
before I saw the bird in flight, I was told by others who had already
seen the bird fly that the rump was white; thus, my expectation may have
molded my perception. Don Crockett's video images, especially the best
shot (http://www.virtualbirder.com/vbirder/rba/elte/elte1.jpg), clearly
show a gray rump, more or less concolor with the back. I remain puzzled
- and troubled - by this discrepancy, despite attempts by others to
dismiss it. However, whatever the actual rump color of the
Massachusetts bird, it now seems that rump color may not be as critical
in separating Elegant from Lesser Crested as previously thought. As
Rick Heil and Jeremiah Trimble have indicated in previous posts, an
examination of specimens at three different museums indicates that
Elegant Tern can have varying amounts of gray on the rump, perhaps
especially so in young birds (I think there is general agreement that
the Massachusetts tern appears to be a first year bird).
Mantle color: Images I took of the bird late in the day on 15 August,
with a low sun almost directly at my back, while it was sitting among
Common Terns (at the same angle in identical light) clearly show the
mantle to be virtually identical in shade to the Commons, thus
suggestive of Lesser Crested. If this is a digital artifact, why does
it affect only the Elegant Tern and not the Commons? David Larsen's
digital images (http://larsonweb.org/birds/southbeach081802.html), taken
on 18 August, are a much better representation of the distinctly paler
mantle that was evident in the field (consistent with Elegant). So, two
images of the bird in direct comparison with Common Terns give two very
different impressions of its mantle color. Go figure.
Bill Structure: The bill structure is another feature that varies in
appearance from one image to another. In the field, I was unable to see
any gonydeal angle at all until I got quite close to the bird (though
others apparently were able to see it from a greater distance than I).
In fact, I commented at the time, only half joking, that I judged the
angle to be about 178 degrees. Yet, in some, though not all, of the
images the gonydeal angle seems quite a bit more pronounced (e.g.,
http://home.attbi.com/~odenews/ELTE0817JT6.jpg). However, as Jeremiah
Trimble has pointed out, this is another feature that varies among
specimens (perhaps related to both age and sex) and thus may be of
limited use in identifying the Massachusetts bird. Jeremiah judges the
bill structure of the Massachusetts bird to be within the range of the
Elegant Tern specimens in the MCZ. I would also note that the gonydeal
angle on the Massachusetts bird seems to fall just short of halfway out
the mandible (to my eye, at least), rather than more than halfway out as
apparently should be the case for Lesser Crested (according to Olsen &
Larsson - but how reliable is this feature?).
One other feature that was evident in the field but not in any images
that I have seen to date (and not mentioned in the discussion so far)
was a faint pinkish or peachy blush on the breast of the bird. This
feature (whether real or imagined!) is consistent with Elegant Tern but
not, to my knowledge, Lesser Crested. The head pattern (eye entirely
encircled by black, with little or no semblance of a white eyering) also
seems to suggest Elegant.
In conclusion, despite some unexplained - and admittedly troubling -
discrepancies in the digital images, as well as ambiguity over the
usefulness of certain characteristics such as rump color, I believe that
there is nothing in the Massachusetts tern that is inconsistent with
Elegant Tern (much as I would like to claim a first North American
record for Lesser Crested!). Nor do I see any reason to invoke the
dreaded hybrid option. Although I see no reason at this point to doubt
that the Massachusetts tern is an Elegant - outside of the sheer
improbability - I (unlike at least one of the observers, it seems)
maintain an open mind and am glad the bird has sparked such a lively and
informative discussion.
Blair Nikula
--
2 Gilbert Lane
Harwich Port, MA 02646
mailto:odenews(AT)attbi.com
web site: http://www.odenews.net/
[ << | >> | ^^ ]
Subject: Re: Elegant vs Lesser Crested
From: Floyd Hayes <floyd_hayes(AT)YAHOO.COM>
Date: 24 Aug 2002 7:45pm
I enjoyed the oxbows as well as the main stream of
commentary on this bird. The bottom line is that I
learned more about ID (especially the revelation that
ELTE can have a gray rump) plus other topics as well,
which is why I joined ID Frontiers. Thanks!
-Floyd
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