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ID-FRONTIERS for March 1-10, 2001
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Messages are displayed in the order they were received.
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| Subject | From | Date | Time |
| Elegant Tern | Steven Mlodinow | Thu, 1 Mar 2001 | 8:21pm |
| Re: Elegant Terns in Europe?? | Laurent Raty | Fri, 2 Mar 2001 | 8:37am |
| Re: Elegant Terns in Europe?? | Jim McCoy | Fri, 2 Mar 2001 | 11:20am |
| Updated home page | Jerry R. Oldenettel | Fri, 2 Mar 2001 | 12:05pm |
| Re: Elegant Terns in Europe?? | Lethaby, Nick | Fri, 2 Mar 2001 | 5:48pm |
| Elegant Terns, again | Paul Lehman | Sat, 3 Mar 2001 | 7:08am |
| Re: Black-backed" or "Newfoundland" Robins | Jean Iron | Sat, 3 Mar 2001 | 8:23am |
| Re: Elegant Terns occurance | Martin Reid | Sat, 3 Mar 2001 | 8:31am |
| Elegant Tern | Steven Mlodinow | Sat, 3 Mar 2001 | 9:54am |
| Radio tagged Great Blue Heron | Howard Vaughan | Sun, 4 Mar 2001 | 3:32pm |
| White-fronted Goose id - wrap up | Dick Newell | Sun, 4 Mar 2001 | 4:20pm |
| Unidentified UK Gull - wrap up | Dick Newell | Sun, 4 Mar 2001 | 4:21pm |
| Re: Elegant Terns in Europe?? | Alvaro Jaramillo | Mon, 5 Mar 2001 | 12:37am |
| Re: Elegant Terns in Europe?? | Alvaro Jaramillo | Mon, 5 Mar 2001 | 12:37am |
| Re: Elegant Terns in Europe?? | Alvaro Jaramillo | Mon, 5 Mar 2001 | 12:37am |
| Re: Elegant Terns in Europe?? | David Powell | Mon, 5 Mar 2001 | 6:18am |
| Ruddy Duck | paullarkin | Mon, 5 Mar 2001 | 10:18am |
| Re: Elegant Terns, again | Lethaby, Nick | Mon, 5 Mar 2001 | 10:45am |
| Fwd: Emperor Goose molts | David Vander Pluym | Mon, 5 Mar 2001 | 12:15pm |
| Re: Fwd: Emperor Goose molts | Korpi, Ray | Mon, 5 Mar 2001 | 2:26pm |
| Re: Ruddy Duck | Malcolm Ogilvie | Mon, 5 Mar 2001 | 2:52pm |
| Re: Unidentified UK Gull - wrap up | Nick Rossiter | Mon, 5 Mar 2001 | 3:35pm |
| The Spanish Elegant Tern online | Ricard Gutierrez | Mon, 5 Mar 2001 | 4:22pm |
| Re: Ruddy Duck | Joseph Morlan | Mon, 5 Mar 2001 | 5:42pm |
| Re: Ruddy Duck | Rich Hoyer | Mon, 5 Mar 2001 | 6:50pm |
| Re: Ruddy Duck | Dave Sibley | Mon, 5 Mar 2001 | 7:33pm |
| Re: Ruddy Duck | Steven Mlodinow | Mon, 5 Mar 2001 | 9:50pm |
| Dark-headed Oxyura | Andrew Harrop | Mon, 5 Mar 2001 | 10:27pm |
| Re: Dark-headed Oxyura | Alvaro Jaramillo | Tue, 6 Mar 2001 | 12:49am |
| Dark-headed Oxyuras | Peter Adriaens | Tue, 6 Mar 2001 | 1:58am |
| A strange Saxicola | Ugo Mellone | Tue, 6 Mar 2001 | 12:23pm |
| Re: The Spanish Elegant Tern online | Phil Pickering | Tue, 6 Mar 2001 | 4:01pm |
| Fwd: Ruddy Ducks | Alvaro Jaramillo | Wed, 7 Mar 2001 | 12:42am |
| Re: A strange Saxicola | Eran Tomer | Wed, 7 Mar 2001 | 7:22am |
| Re: The Spanish Elegant Tern online | norman van swelm | Wed, 7 Mar 2001 | 8:44am |
| R: Re: A strange Saxicola | Ugo Mellone | Wed, 7 Mar 2001 | 9:56am |
| Re: The Spanish Elegant Tern online | Florida Nature Tours | Wed, 7 Mar 2001 | 10:34am |
| Black-backed robins | Ian Mclaren | Wed, 7 Mar 2001 | 10:39am |
| Steller's/Blue Jay | Calvin Gehlen | Wed, 7 Mar 2001 | 10:53am |
| House Martin hybrids | Peter Wilkinson | Wed, 7 Mar 2001 | 2:00pm |
| Re: Black-backed Robins | Dave Sibley | Wed, 7 Mar 2001 | 3:27pm |
| Re: The Spanish Elegant Tern online | norman van swelm | Wed, 7 Mar 2001 | 3:56pm |
| Re: Black-backed Robins | Ian Mclaren | Thu, 8 Mar 2001 | 9:53am |
| FW: [BIRDWG05] AZ sapsuckers | Rich Hoyer | Sat, 10 Mar 2001 | 5:54pm |
| Re: AZ sapsuckers | Rich Hoyer | Sat, 10 Mar 2001 | 10:40pm |
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Subject: Elegant Tern
From: Steven Mlodinow <SGMlod(AT)AOL.COM>
Date: 1 Mar 2001 8:21pm
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Greetings All
A most interesting question.
First, from my home base in the Pacific Northwest, Washington, we are seeing
a change in Elegant Tern patterns. Last year was not an ENSO year, yet
several Elegant Terns were seen in Oregon, and at least one was in Washington.
Second, the mystifying Elegant Tern situation in Europe is not all that
different from the Black-tailed Gull situation in North America. They show up
in Virginia, Atlantic Canada, Rhode Island, Texas -- seemingly everywhere but
the Pacific Northwest. If my memory is serving me correctly, there are almost
as many records from eastern North America as there are from Alaska
(depending on how many birds you think are involved. Given age differences,
it is clear that at least a couple birds have been on the east coast). The
Black-tailed Gulls are clearly not hybrids, but could be escapes I guess. On
the other hand, this gull species does not seem to be a common collection
bird. Another example, somewhat along the same lines, is Large-billed Tern.
There are three records for this South American bird in the US/Canada: from
Ohio, Illinois, and New Jersey. Not at all what one would expect.
Third, the argument regarding other vagrants from the same area is a bit
weak. Yes, Elegant Tern is the only NW Mexico/southern California seabird to
have occurred in Europe. On the other hand, there aren't very many species of
birds limited to that region. Beyond the Elegant Tern, there is Craveri's
Murrelet, Xantus's Murrelet, Black Storm-Petrel, Ashy Storm-Petrel and
Heermann's Gull. Given habits of the murrelets and the storm-petrels, I'd
find them far less likely than Elegant Tern to show up in the eastern U.S. or
Europe. Heermann's Gull would seem to be about as likely as Elegant Tern, or
perhaps more likely, being a gull and all. In any case, there are not a bunch
of species from the Elegant Tern's homeland for comparison, and the argument
that none have occurred in Europe is, therefore, a bit specious.
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Subject: Re: Elegant Terns in Europe??
From: Laurent Raty <l_raty(AT)HOTMAIL.COM>
Date: 2 Mar 2001 8:37am
Hi all,
First I would like to thank everybody for the time you took in answering to
my questions.
Here are a few things I wanted to add in answer to some of the comments that
I received up to now.
------
First, a few quotes from a mail that Kimball Garett sent directly to me and
to which I would like to answer:
> Another relevant point. Non-breeding ranges of Sandwich and Elegant
> Terns broadly overlap off western central America and nw. South
> America; a large number of Sandwich Terns cross into the Pacific Ocean
> (and a very few have made it north to California with Elegant Terns). It
> is entirely plausible, therefore, that Elegants might occasionally follow
> Sandwich Terns back into the Caribbean/Atlantic. It is also quite
> plausible that North American Sandwich Terns make it to the western
> Palearctic at times (where they would surely be undetected among their
> counterparts there); hurricane tracks could perhaps sometimes account
> for this.
Some acuflavida do it: there is one record from the Netherlands, of a ringed
bird found dead in winter. However, I don't feel this can account for the
number of sightings we have in Europe. If this was the explanation, I would
expect to see a dilution effect - less birds on the east coast than in the
Caribbean and still less birds in Europe than on the east coast. This is
apparently not the case.
> In any case, I think you are
> incorrect in looking for a "Strait of Magellan" explanation for the
> arrival of Elegant Terns in the Atlantic Ocean; a far more plausible
> scenario is the crossing of the Isthmus of Panama or the Isthmus
> of Tehuantapec, something that is routine for the closely related
> Sandwich Tern.
The "Strait of Magellan" theory is not mine - and I don't find it really
plausible either. However, it has the advantage to explain how more birds
could reach Europe: if they cross the Atlantic from Brazil to West Africa,
they obviously won't be seen in the States.
> I would have to wonder just what kind of trafficking of "shipments of
> exotic seabirds from wintering grounds in W South America" really takes
> place. But these human-assisted scenarios do at least have to be
> considered.
There are known shipments of Inca Terns from S America and a few escape
birds have even been seen in Europe (at least in Ireland and northern
France). However, I don't know any shipment of Sterna-type terns.
------
About latitudinal distributions:
I fully agree that we can not compare the situation in the Pacific to that
in the Atlantic without considering carefully what actually happens in both
oceans.
Actually, I did not expect, and was at first surprised to see that the
Pacific vagrants we had in Europe all were at latitudes acceptable for their
species at the time they were seen. In any case, none are unusually far
North.
Ancient Murrelet spent summer in an Alcid colony on Lundy, roughly 51°N, the
latitude of the southernmost islands of the Aleutian Chain. Aleutian Tern
at Farne Is, Northumberland, in late May, was about 56°N, which is the
latitude of the Alaska Peninsula where the species breeds. The Crested
Auklet collected off Iceland in Aug was 66°N, roughly the latitude of the
Bering Strait. The Parakeet Auklet in Sweden was 58°N in Dec, which is the
latitude of Kodiak Is in AK. Lastly, the Glaucous-winged Gulls on the Canary
Is and in Morocco were somewhere between 30 and 40°N, which is the latitude
of Baja California, where a non-breeding glaucescens would not be an
abnormal find.
I'm not at all expert in currents (so, please, correct me if I'm wrong) but,
actually, my impression is that the situation northeast Atlantic is not that
much different from that in the northeast Pacific - as long as you don't
compare California to France, but to Morocco. The California Current has a
counterpart here, at a similar latitude, known as the Canary Current (I
apologise if some current names are not exact, my atlas is in French). In
both oceans, there is a westward North-Equatorial Current, roughly at 20°N.
This current turns to the north, near the Philippines in the Pacific and in
the Caribbean's in the Atlantic, resulting, in both oceans, in strong SE-NW
warm currents - the Gulfstream in the Atlantic and the Kouro-Shivo in the
Pacific (that ends up along the coasts of WA-BC-AK).
The main difference between Atlantic and Pacific is due to the configuration
of northern land masses: there is no counterpart to AK in Europe. AK stops
the Kouro-Shivo, which therefore does not enter the Bering Sea. In Europe, a
part of the Gulfstream enters the N Atlantic, passing between Europe and
Iceland, and continues into the Norway Sea (North Atlantic Current) to warm
up the northern Norway coasts.
Broad vegetation limits along the west coast and along the Atlantic European
and North African coasts are similar - coniferous forests above 60°N (with
the exception of the Caledonian Forest that is a bit further south),
deciduous forest between 40 and 60°N, mediterranean vegetation from 32 to
40°N and subdesertic steppes and deserts further south. The main difference
is again between the Bering Sea and the Norway Sea: coniferous forests reach
a latitude along northern Norway coast, that they do not reach on the Bering
Sea coasts, where they are replaced by tundra.
One can also compare the ranges of seabirds in the two regions. Having
consulted an atlas, together with various bird books, if feel this leads to
the following results:
- North-breeding seabirds (loons, Leach's Storm-Petrel, sea ducks,
phalaropes, jeagers, glaucous gull, Arctic Tern, murres) have very similar
southern limits to their breeding distributions on both continents. Only
the extreme northern species have latitudinal distributions that differ to
some extent (Sabine's Gull, a.o.), as they do breed in the Bering Sea but
not in Norway.
- Two exceptions to this rule are Fulmar and Kittiwake, that breed
significantly further SOUTH in Europe than on the west coast.
- Among more southerly gulls, Common/Mew and Herring (not including
Yellow-legged) have, again, very similar breeding ranges along both coasts.
- On a general base, the winter ranges of many of the above species are more
strongly affected than their breeding ranges, as the Bering Sea, in winter,
becomes obviously too cold. Many birds leave it, and their winter range is
therefore limited to the north at roughly 60°N in the Pacific. The whole
winter range of these birds is usually displaced by 5-15° to the north in
Europe, as compared to the west coast.
- However, some species that would not, anyway, reach the latitude of the
Bering Sea in winter, as the jeagers, are less affected and have similar
winter northern limits in both ocean.
- South of Europe, Brown Booby has also the same latitudinal limits, both in
winter and summer, in both oceans.
- Royal Tern, that could be of interest as it is closely related to Elegant,
has breeding range much further south in Africa than on the west coast.
However, it could probably be argued that this is merely due to a lack of
adequate breeding sites further north off the Sahara, and the northern
limits of the non-breeding ranges of the species are, again, rather similar
in both oceans.
Elegant Tern is not a northern breeder and was never seen in Europe during
winter. There is no reason to believe that its distribution should be in
anyway determined by the winter temperature of the Norway Sea above 60°N...
At 55°N, the latitude at which the Danish Elegant was displaying, the
typical breeding seabirds encountered in Europe include: Fulmar, Common
Eider, Herring Gull, Mew Gull, Kittiwake, Arctic Tern and Common Murre (and
Parasitic Jeager is very close). All these are present on the west coast
but, except perhaps for a few Common Murres at the southern limit of their
distribution, none of them should normally breed close to a displaying
Elegant Tern. If currents and climate act on the distribution of Elegant
Terns, they also act on the distribution of all other species. Why would
this action result in separating Elegant from all the above species on the
west coast and not in Europe?
------
A word about hybrids:
One can't know how hybrids between two species will look before to have
seen them. Among other things:
- F1 hybrids between two stable species do not need to be variable, they can
be extremely stable and all have the same appearance. A high variability
usually occurs when you have hybridising populations. Note that a F1 hybrid
always inherits exactly 50% of its genes from each of its 2 parents (not
taking slight variations due to heterochromosomes or mtDNA into account).
The situation becomes totally different as early as you have a F2 hybrid. If
you back-cross a F1 with one of its parent species, the F2 will inherit 50%
of the genes of its pure parent, plus 50% of the genes of its hybrid parent.
However, there is NO reason to assume that these last 50% will be composed
of 25% from each parent of the F1. What happens is not exactly like, but
comparable to what would happen if you mixed the 1000 of two different
objects in a bag, than took 1000 objects in the bag with your eyes closed.
The proportion of each type of object is not a deterministic process any
more: it becomes a random or stochastic process, that you can only describe
with statistics. While a F1 will always be EXACTLY 50% of each parent
species, a F2 is only ON AVERAGE 75% of one species and 25% of the other,
but the genetic proportion could theoretically vary from 50%-50% to 100%-0%.
As a result, F2 are always much more variable than F1. Similarly, if you
cross two F1, the offspring will be on average 50%-50%, but it could
theoretically range from 0%-100% to 100%-0%.
- F1 hybrids can look different according to which species was the male and
which species the female in the parent pair.
- F1 hybrid can be of different types according to a dominant or recessive
gene in one of the parent species (remember "Lawrence's" and "Brewster's"
Warblers).
- F1 hybrids can show characters that are either within the range of
variation of one of the parent species, either intermediate, either
different. In particular, some hybrids CAN be larger than both parent
species (this is not at all an extremely rare phenomenon, I think it has
even been given a particular name but I just can't put my finger on it right
now - "outbreeding" comes to mind but I'm not sure it applies to hybrids -
perhaps someone can help?).
------
In answer to Ricard Guttierez:
Ricard, understand, I don't want to go against you or your paper in
particular. If I cited you, it was because you wrote one of the most
complete and recent articles on the subject.
However, if I read you correctly, among the hybrids LCxSandwich you cite,
all are likely to have been produced by only 2 pairs (Elsie at Farne Is and
a hybrid pair near Valencia). There would therefore be a probability of 50%
that the male was the same species in both pairs. If there are two hybrid
types, as in Blue-winged x Golden-winged Warblers, there could even be a
higher probability that the hybrids were all of the Sandwich type - this
would depend of the frequency of some alleles of some genes in one of the
species - neither you, me or anybody knows anything about it. The fact that
these two pairs produced Sandwich-type hybrids can not, in anyway, prove
that an orange-billed type does not exist.
Something else intrigues me: actually, Malling Olsen & Larsson do refer to
such birds when they discuss LC hybrids. They wrote: "Bill dirty yellow, a
shade paler towards tip and with faint greyish tone in centre of upper
mandible (Steele & McGuihan 1989) or orange with yellow tip (Verroken
1990)" - was it proven that this last description referred to pure LC?
Another thing that I feel surprising is that the second 1987 ringed bird
from Banc d'Arguin could not be identified. I don't understand how one can
conciliate the idea that a hybrid will never look like a pure Elegant with
the other idea that it could be impossible to make the difference between a
hybrid and a pure bird when having a bird in the hand.
Of course, we don't need to build a hybrid or variant theory to explain the
appearance of every common bird because we know these birds are there and we
know what they are. At best, the number of individuals that would be
explained by this theory would be negligible. But, think about it: when you
see something looking like a classical Yellow-legged Gull in Spain, you
don't start thinking about a LBB x Herring hybrid... While the bird COULD be
one, actually. If you were a North-American birder looking at the same bird
somewhere on the east coast, you would consider it. Similarly, when I see a
Great Tit in my garden, I don't think it's an escape but it COULD also be
one. And if I lived in California, I would take this possibility into
account (this actually occured - but not to me ;-).
About mathematics:
Try multiply the probability to have an Elegant crossing America (as
indicated by the number of sighting on the east coast), by the probability
for it to cross the Atlantic and end up in NW Europe (as indicated, say, by
the number of sightings of Royal Terns in NW Europe, although this would
already be an overestimate because a good part of these could actually come
from Africa) and you will get an exaggeratedly small result. If you
restrict the area that the bird has to reach to one small island in France,
then multiply the probability by itself to have two birds reaching the same
site *independantly* (the second joining the first 10 years after its
arrival), the result is ZERO.
Trying to look at the problem from another angle: let's be exaggeratedly
optimistic. The east coast Royal Tern population is estimated by Del Hoyo
at 34,000 pairs. Forgot about the additional 1,000 pairs or so that breed
in the Caribbean's. Forgot about the S American population that is not
accurately estimated. Assume the east coast population is overestimated by
50% (unlikely). We are left with 34,000 adult Royal Terns on the east
coast, plus associated immatures, that could do the way to Europe. Now,
take the Elegant population: it is estimated at 30-50,000 pairs. Choose the
highest value. Assume that there is a regular crossing in Central America,
for this example, of 1% of the population: this would leave us with 1,000
adults plus associated immatures every winter in the Caribbean's. Assume it
is possible that all these birds have gone unnoticed up to now (unlikely
again IMO). Now, suppose these will either go back to the Pacific, either
cross directly to Europe from the Caribbean's, but that they won't head
north, so they don't have to be seen on the east coast (once more, this is
unlikely). Even this way, we are left with an almost certainly strongly
underestimated 34 Royal for 1 Elegant! If we had 6 Elegant in Europe
during the last 30 years, where have been these 200 (American!) Royal Terns?
Again, I do not have anything against any particular sighting of Elegant in
Europe. As far as I know, each of them could perhaps be acceptable if taken
separately, which is what we, in RC's, often do. Also, as RC's in Europe
are national, we usually do not dispute the validity of sightings accepted
by other committees, we accept them as valid and we forgot to question the
whole phenomenon.
I don't know for sure which ones of the sightings would have to be
questionned more than others, although I must concur that the Belgian and
French birds seem less "good" than others to my eye. Anyway, the whole
pattern is, to me, simply unbelievable. And it's because of the whole
pattern that I can't buy the theory that these birds are all genuine vagrant
Elegant Terns. I have to search for another explanation and, then, there's
not much choice: either some (at least) of the birds are not genuine
vagrants, either they're not genuine Elegant Terns.
------
Lastly, Steven Mlodinow wrote:
> Second, the mystifying Elegant Tern situation in Europe is not
> all that different from the Black-tailed Gull situation in North
> America. They show up in Virginia, Atlantic Canada, Rhode
> Island, Texas -- seemingly everywhere but the Pacific Northwest.
Reverse migration (though I'm not sure this argument has been advanced for
gulls) of an immature bird would lead it from Japan, through the Kouriles,
Kamchatka Peninsula and Bering Strait, to the Beaufort Sea. Continuing this
route, the bird would reach Baffin Is. Then, I guess it could be argued
that it headed south because of the climate or that it joined a local gull
flock.
The same type of phenomenon, a few degrees further east, could explain in
part why Aleutian Tern showed up in Britain, while it has never been seen in
N America away from AK. And the reverse route would take an Iceland Gull to
Japan, which is something that, apparently, does occur too...
But, IMO, nothing similar can be assumed for Elegant Tern.
> Another example, somewhat along the same lines, is Large-billed
> Tern. There are three records for this South American bird in the
> US/Canada: from Ohio, Illinois, and New Jersey. Not at all what
> one would expect.
According to Del Hoyo, LBTE is also recorded from the West Indies and
Bermuda, which could trace a route to the American records. That said, I
fully agree these records were unexpectable.
> In any case, there are not a bunch of species from the Elegant Tern's
> homeland for comparison, and the argument that none have occurred
> in Europe is, therefore, a bit specious.
Yes. Actually, I merely wanted to show that the argument that other
American Pacific species have occured in Europe, in support to the
likelihood of Elegant records, is weak too, as these did not come from
Elegant's homeland.
Best regards,
Laurent
[ << | >> | ^^ ]
Subject: Re: Elegant Terns in Europe??
From: Jim McCoy <jfmccoy(AT)EARTHLINK.NET>
Date: 2 Mar 2001 11:20am
Forgive my intrusion into this discussion, but one question glares
out at me among the statistical observations, structural discussions,
and laborious comparisons to other species' vagrancies:
Why can't these six sightings in 30 years be related, i.e. an expression
of a single unknown phenomenon, or set of related phenomena? If we
understood the phenomenon, we might quickly and easily dismiss the
apparent obstacles, e.g. why there aren't more eastern U.S. sightings.
It seems that we're going to an awful lot of trouble to disprove the
most obvious identification. These birds have convinced a lot of people
that they were Elegant Terns, despite the seeming improbability. I have
to take seriously the notion that they *really were* Elegant Terns, and
that they were untroubled by the awkwardness that we're having in
explaining their presence.
We've known about Venus for untold thousands of years, but until a few
hundred years ago, we couldn't explain why it stayed so close to the
horizon while Mars, Jupiter, and Saturn were cruising across the zenith.
That our scientific understanding has grown, and at an accelerated rate,
is no excuse for hubris. By any explanation, the appearance of these
birds is a mystery.
It seems that the best way to solve it is to review the facts -- we have
had six birds that look just like Elegant Terns showing up in Europe --
and not ignore them until we have more solid ground on which to tread in
constructing a theory of how these birds got there. If they're Cayenne
Terns, demonstrate that for us; if they're escapees, document it. But
please don't say they're not Elegant Terns just because you can't explain
it.
Jim McCoy
jfmccoy(AT)earthlink.net
Redmond, WA
-----Original Message-----
From: NBHC ID-FRONTIERS Frontiers of Field Identification
[mailto:BIRDWG01(AT)LISTSERV.ARIZONA.EDU]On Behalf Of Laurent Raty
Sent: Friday, March 02, 2001 7:33 AM
To: BIRDWG01(AT)LISTSERV.ARIZONA.EDU
Subject: Re: [BIRDWG01] Elegant Terns in Europe??
[ << | >> | ^^ ]
Subject: Updated home page
From: "Jerry R. Oldenettel" <Borealowl(AT)AOL.COM>
Date: 2 Mar 2001 12:05pm
I have updated the recent sightings section with text and pictures and added
my NM winter report to my home page at:
http://hometown.aol.com/borealowl/
Jerry R. Oldenettel
Albuquerque, NM
borealowl(AT)aol.com
[ << | >> | ^^ ]
Subject: Re: Elegant Terns in Europe??
From: "Lethaby, Nick" <nlethaby(AT)TI.COM>
Date: 2 Mar 2001 5:48pm
This message is in MIME format. Since your mail reader does not understand
this format, some or all of this message may not be legible.
----INCLUDING text/plain MIME SECTION----
If I recall correctly the Glaucous-winged Gull in Morocco was an adult. Here
in Santa Barbara, which is a couple of hundred miles N. of Baja California,
Glaucous-winged Gulls are already at best uncommon (perhaps 30 birds
wintering here) and all the ones I've seen are 1Y birds. Therefore I suspect
an adult in Baja would be unusual, although I'm sure they occur there from
time-to-time.
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Subject: Elegant Terns, again
From: Paul Lehman <lehmfinn(AT)BELLATLANTIC.NET>
Date: 3 Mar 2001 7:08am
IDFrontiers:
I have been following the Elegant Tern thread only late in the game so
likely missed a bit (which will probably show in my comments below!),
but I would briefly add a couple minor points:
1) Over the past many years I have seen the photos of most of the
European Elegant Terns published mostly in "Birding World" and perhaps
"Duth Birding" magazines, and have always thought that some of them
looked a bit "off" for that species, especially the early ones. I could
never really say they absolutely weren't Elegants, and I can't find an
obvious better fit, but they did strike me as looking just a bit odd and
not like 100 percent typical Elegants, so i had wondered about possible
hybrids, etc. (I lived in California for 20
years and have seen many thousands of Elegants.) Given these comments
are based just on gut feel and nothing more precise, you can take these
for what they're worth!
2) The analogy of Black-tailed Gulls along the North American East Coast
is both accurate and perhaps inaccurate. There are a fair number of
people who think that the surprising number of BTGU records between
Virginia and Newfoundland are largely the result of just two or three
individual birds floating up and down the coast for the past 5+ years,
occuring in New England and the Atlantic Provinces in summer, and from
New York to (mostly) Virginia in winter. Such a scenario is particularly
strong when one looks at the timing of the records and plumages involved
with all the sightings in Virginia, New Jersey, and New York. There are
also a few people who think the birds got over here via some sort of
human-assisted method, and are thus of questionable origin. I do not
subscribe to that theory much given the intervening BTGU records in
places like Texas, Yucatan, Alberta, but the situation is not clear in
any case.
Certainly it seems as though some of the European records of
Elegant-type Terns also could involve the same few birds wandering the
northeast Atlantic with the Sandwich Terns for multiple years, once
it/they ended up in the wrong ocean via a probable Panama cross-over.
(The same is true with a couple recurring Sandwich Terns in southern
California that associated (and even likely interbred) with Elegants,
and which turned up year after year.) A hybrid-looking bird turned up
once slightly farther north in the Monterey, California, area.
Paul Lehman
[ << | >> | ^^ ]
Subject: Re: Black-backed" or "Newfoundland" Robins
From: Jean Iron <jeaniron(AT)SYMPATICO.CA>
Date: 3 Mar 2001 8:23am
Here are comments on Ian McLaren's post (attached below) regarding
"Black-backed" American Robins.
The Birds of Canada (Godfrey 1986) says the Black-backed subspecies (race)
nigrideus of the American Robin breeds in northern and central Quebec,
Labrador and Newfoundland. Godfrey describes nigrideus as "averaging"
darker generally than migratorius, adult males with black of head and nape
extending to upper back. This appears to be the core range of nigrideus.
Interestingly, the nigrideus subspecies has not been recorded in Ontario
(James 1991). It should occur in eastern Ontario as a migrant.
Ken Parkes (Auk 105(3): 598-601, July 1988) in a review of Pyle et al.
(1987) says this about American Robins: "In addition to the caveats listed
for sexing this species, it should also be pointed out that females of the
Newfoundland/Labrador breeding race nigrideus, which migrates into the
eastern United States, are fully as richly colored as males of migratorius
of equivalent age." Parkes' comment may explain why Bruce Mactavish is
seeing only 20% Black-backed Robins in Newfoundland and coastal Labrador,
if he's recording only bright adult males as nigrideus. Perhaps the duller
first year (first basic) birds of both sexes and adult (definitive basic)
females of nigridius are being called migratorius.
Two points about subspecies: (1) Most subspecies recognized by the AOU 1957
(last Check-list to list subspecies) and Godfrey (1986) are broadly clinal,
leading some to say that there are no subspecies, only clines; (2) it is
not unusual to see individuals in the breeding population of one race that
appear to be another race. For example, Ross Harris (pers. comm.) of
Toronto studied the nominate griseus race of the Short-billed Dowitcher on
the breeding grounds near Schefferville, Quebec, close to the border with
Labrador. He once saw a bird there that appeared to be the hendersoni
subspecies. Was it a hendersoni or an extreme griseus? Short-billed
Dowitchers in northern Ontario can appear similar to griseus or hendersoni
or intermediate (James 1991). I could list many more similar examples. So
having nigrideus-like robins in the breeding range of migratorius or vice
versa is not unusual as this happens in many other subspecies.
Ron Pittaway
Co-editor, Ontario Birds
Box 619
Minden ON K0M 2K0
E-mail: jeaniron(AT)sympatico.ca
At 02:59 PM 2/28/2001 -0400, Ian Mclaren wrote:
>All:
>After e-conversations with Bruce Mactavish I'm launching
>("starting" being more appropriate to hares) something new,
>although it may go nowhere. There are lots of references to the
>"Black-backed" or "Newfoundland" Robin, _T. migratorius
>nigridius_, but the situation remains hazy at best. Probably the
>last original word was in Todd's massive "Birds of the Ungava
>Peninsula." Most other more recent references are based on
>previous ones, although Phillips seems to have looked at some
>specimens in coming to some uncharacteristically conforming
>conclusions.
>
>All sources since Aldrich and Nutt defined the subspecies
>recognize that individual "black-backed" birds can occur widely,
>where they might qualify either as morphs or extremes within the
>normal range of _T. m. migratorius_. Todd accordingly decided to
>restrict subspecies status to birds of coastal Labrador and
>Newfoundland, where he thought the black-backed form "becomes
>predominant in the population." He tended to dismiss this
>possibility for northern areas. Without seeing specimens, he
>thought that Ungava Bay birds did not qualify, although Aldrich
>(accessibly quoted in Bent) had certified two males collected by
>Turner in 1884 from Chimo (now Kuujuaq), at the base of Ungava
>Bay. As a personal aside, I entered in my June 1951 (!) diary observations
>of nesting robins at Kuujuaq that I rated as "black-backed." Others since
>Todd have retained "N. Quebec" or variants of that as within the range of
>_nigridius_.
>
>One trouble is that Bruce Mactavish has seen only a small fraction of
>birds, "20% at any season") that he would rate as "black-backed" in SW
>Newfoundland and along the Labrador coast. And there remains the problem
>of wider occurrences. Around here (NS), some black-backed males do indeed
>nest (see Tufts, "Birds of NS"); I had one on my street two years
>running). Although there is birder talk of "Newfoundland robins"
>wintering in NS, I haven't seen black-backed birds then, although there
>are fair numbers passing through in spring.
>
>So, here are a couple of questions.
>
>1) is there indeed any core range for "predominantly" black-
>backed birds (maybe a majority of males would do?) that might
>sustain continued designation of _nigridius_? Maybe it's still
>possible that Ungava Bay drainage would qualify. And, maybe
>our Quebec colleagues have some more recent insights on this.
>
>2) There are lots of references to migrant or wintering specimens
>deemed _nigridius_ in eastern-to-midwestern localities. Do any of
>you out there have a sense of when good numbers of this
>morph/subspecies appears in their area. This might give us some
>clues about origins. Todd notes that the usual "birds-of-a-feather"
>rule might apply to migrant _nigridius_ tending to flock together.
>
>All this may be too arcane, particularly since no one is going to
>mount a "split" on this issue.
>
>Cheers, Ian M
>Ian A. McLaren
>Biology Department phone: (902) 494-2565 (W)
>Dalhousie University (902) 429-7024 (H)
>Halifax, NS B3H 4J1 Fax: (902) 494-3736
Jean Iron
President, Ontario Field Ornithologists
9 Lichen Place
Toronto, Ontario M3A 1X3
Canada
Phone: 416-445-9297
e-mail: jeaniron(AT)sympatico.ca
Web Page: http://www.interlog.com/~ofo
[ << | >> | ^^ ]
Subject: Re: Elegant Terns occurance
From: Martin Reid <upupa(AT)AIRMAIL.NET>
Date: 3 Mar 2001 8:31am
Dear all,
Comments on some of the factors being considered when assessing this
interesting phenomenon:
Laurent Raty's use of statistical likelihood is a bit misleading -
especially regarding the 2nd bird that was discovered in the same tern
colony in France 10 years into the known visits of the first bird. Firstly,
these birds were not paired (each had found a Sandwich Tern mate), and a
good explanation is that they are the same sex; secondly, what do we know
about this tern colony: how large is it? how much of it is monitiored? - in
the absence of any data to the contrary, it could be that both birds have
been present at the colony for the same time period, but the 2nd bird had
previously been using a different location in the colony that allowed it to
go undetected for years - why not? Even if the 2nd bird arrived at the
colony at a later time than the first, it seems reasonable to speculate
that these "vagrants" (be they natural or human-assisted) are somehow
finding a wintering group of Sandwich Terns to associate with, and then
follow them to wherever they happen to breed; there are other examples of
vagrant "flock" species finding each other in large wintering groups of a
close relative.
If you use statistics to refute this, then what about examples of even less
likelihood:
1) There have only been two Belted Kingfisher records for Great Britain
(plus two more in Ireland): the first was in 1908 at Sladesbridge, north
Cornwall. The second record was 71 years later in 1980 (note the numerical
permutation of the date) at EXACTLY THE SAME PLACE.
2) There is only one record of Cape May Warlber in the Paleartic: a male
singing at Paisely Glen, near Glasgow, Scotland (photographed and
tape-recorded) on 17th June, 1977. The location of this bird was in easy
sight distance of the birthplace of James Alexander Wilson, the
Scottish-American ornithologist who first discovered the Cape May Warbler.
3) Britain's first Chimney Swift was found at a headland and visited by
many birders during its first three days, when suddenly a 2nd Chimney Swift
appeared with it.
There are just three that I recall - I'll bet that there are many other
such coincidences that defy explanation - it's part of the magic of birds!.
One possible explanation as to why there are more records from western
Europe than eastern America, might be that Elegant Terns have a strong
spatial orientation, such that they seek out a coastline where the Sun
rises inland and sets at sea - or put another way - they are used to the
ocean being to the west of the land. The mediterranean Spanish record
would be at odds with this, but all the other breeding-colony records are
at locations where the the relationship between the sea/land and Sun
tracking would be very familiar, unlike most American East Coast locations.
Displaced birds might wander until they find the right spatial alignment
for breeding; birds at breeding colonies are much less ephemeral than
migrants, and are thus more likely to be found. Is this a far-fetched
notion? are there any species known to exhibit such a coastal-alignment
preference?
Although Laurent acknowledges the situation with Large-billed Tern, I feel
the point is not that there may be a "record bridge" via the Caribbean, but
that this is an inland (large) river species, with FEWER trans-oceanic
records than Elegant Tern - i.e. it is another example of Terns being
capable of dispersing across alien habitat (there may be others; in their
normal range are White-winged Terns known for using/crossing large bodies
of water, or do they follow coastlines? ).
Regards,
Martin
Martin Reid
upupa(AT)airmail.net
http://www.martinreid.com or http://www.cyberramp.net/~upupa
[ << | >> | ^^ ]
Subject: Elegant Tern
From: Steven Mlodinow <SGMlod(AT)AOL.COM>
Date: 3 Mar 2001 9:54am
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Greetings All
A couple more brief comments.
Regarding the hybrid issue. I agree with Laurent, that it is hard to be
certain that a hybrid could not mimic an Elegant Tern with near perfection.
Regarding latitude. The Morocco GW Gull is not exactly from a latitude which
is typical for GW Gull in North America. They are uncommon that far south as
opposed to abundant further north. Also, the Heermann's Gull which wintered
in Ontario was way off base in both latitude and longitude.
Finally, I HATE actual using numerical probability estimates for bird
occurrence. I remember when a Curlew Sandpiper was reported from Chicago in
late May. It was seen by only two observers, and part of the rationale for
dismissing the occurrence was that the odds of it occurring were a billion to
one (and the way in which that estimate was made was carefully delineated; it
was not a figure of speech). The next year, another one showed up, in almost
exactly the same place, and lots of folks got to see it. We simply do not
understand bird movement, and the reasons for such, well enough to throw out
numbers like that. It may well be that Elegant Terns are more prone to long
distant vagrancy for than Royal Terns for factors we are totally ignorant of.
Anyway, I am starting to veer off-topic here and will stop.
It is a most interesting discussion.
Best Wishes and Good Cheer
Steven Mlodinow
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[ << | >> | ^^ ]
Subject: Radio tagged Great Blue Heron
From: Howard Vaughan <howardandrea(AT)VAUGHANH.FSNET.CO.UK>
Date: 4 Mar 2001 3:32pm
This is a multi-part message in MIME format.
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Evening all,
Having just returned from a family holiday in Florida I have a several =
enquiries to make. =20
1: Immature Great Blue Heron at Gatorland just north of Kissimmee on =
the 23rd February 2001 with large yellow tag on each wing with the =
legend 05 and a radio tag on the back. Was being well fed with bits of =
sausage for feeding the gators! I would be interested in finding out =
any info about its history.
2: Also on the same day at Gatorland I had a cracking Northern =
Waterthrush. I am aware that they winter in southern Florida but was =
not expecting on as far north as Kissimmee.
3: Likewise I was surprised to find 7 Purple Martins at the nest boxes =
in Disney's Epcot Centre.
4: Whilst on the Kennedy space centre tour we had a Crested Caracara by =
the roadside. I was certainly not expecting one here. Is this unusual?
5: I also had a Caracara along Southport Road that goes to the southern =
end of Lake Toha to the South East of Kissimmee. I hoped to find them =
here. The bird had a large blue ring on its left leg. As with the =
Heron, any info would be gratefully received.
I hope I am not asking too much but I am an inquisitive sort!
All the best and good birding.
Howard Vaughan
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[ << | >> | ^^ ]
Subject: White-fronted Goose id - wrap up
From: Dick Newell <dick.newell(AT)APPLEONLINE.NET>
Date: 4 Mar 2001 4:20pm
With reference to the picture of "white-fronted geese" on
http://www.cambridgebirdclub.org.uk/photos.htm
The answer is that they are indeed Greenland White-fronts, flavirostris,
confirmed by a number of people who have gone back to have a critical look.
The reason that I put up this "quiz" was because some people who saw my
picture originally were non-committal about the id or said they thought they
were European White-fronts - which then made me uncertain. I believe the
picture is a faithful representation of the birds, however distinguishing
pink/orange, darkness/lightness, extent of white tail tip, and size of the
white front when flaring may be present are all points of uncertainty,
especially in a single photograph.
Of the 15 people who originally responded (thank you all very much) the
votes were:
Favouring Greenland WF 9
Favouring European WF 3
Don't know/non-commital/no opinion cast 4
Which is probably more decisive than one gets with the average gull quiz.
From here on I will summarise some points from the responses:
Most useful was a reference to some pictures on
http://hem.fyristorg.com/nonne by Björn Anderson
John Stenersen highlighted the difficulty:
"In one case I photographed a group [of Greenland White-fronts] at two
different occasions under very different weather conditions. When I watched
the photographs I could swear they showed the two different subspecies..."
Rob van Bemmelen said: "the birds look extremely dark (compared to what I
see in Holland)"
However, another Dutchman said:
"This race [flavirostris] is very much darker brown than the ones on your
site and the bill is not only much more orange but also longer and
bigger-looking."
Graham Catley noted: "looking at your photo the bird that is back
on to the camera certainly has a very narrow tail tip band [supporting GWF].
The belly barring, head and bill shape on the side-on adult also look very
Greenland to me"
And finally, Richard Millington, after going to see the geese, said:
"A nice chance to compare bills. Its amazing how long as opposed to deep all
the GWfs bills are; I saw one as showing some pinky grey tones at the base,
but all looked otherwise similarly yellowy-orange (plus varying age-related
tip colour). And good to see the the tail patterns checking out to plan."
So there you have it - I learned something.
Of course, there is always the 2 goose flock theory.
Dick Newell
[ << | >> | ^^ ]
Subject: Unidentified UK Gull - wrap up
From: Dick Newell <dick.newell(AT)APPLEONLINE.NET>
Date: 4 Mar 2001 4:21pm
The replies to the identification problem posed with the unidentified gull
on: http://www.cambridgebirdclub.org.uk/photos.htm were not unanimous (what
a surprise!), there being votes for both michahellis and cachinnans.
However, there is a rational explanation and the bird appears to be a
Yellow-legged Gull (michahellis) in its 3rd (not 2nd) calendar year. It was
identified most succinctly by Menotti Passarella (thank you Menotti) who
said:
"The mystery appears to be a second summer (second alternate) Yellow-legged
Gull (Larus michahellis), to me."
Although this bird superficially looks as though it is in 2nd winter
plumage, it is actually a year older when it should be in 3rd winter
plumage. However, this November bird seems to be behind schedule in its
moult. The comments in the various responses can probably best be summed up
by the reply from Koen Verbanck (thank you Koen)
"this bird looks like a michahellis: I think that this bird is a second
summer (3cy) bird with a strange moult-pattern (based a.o. on the large
amount of adult looking secondaries, quite a few grey median & lesser
Wing-coverts, tail which is already largely white with only little remains
of the black tail-band ; strange is the lack of adult-looking greater
coverts. This age would also explain the white mirror on P10). The bill
pattern is quite variable in michahellis in this stage but isn't unusual:
although the yellow tip is quite extensive, there is also a less clear
yellow bill-base. Normally I would expect to see more clear yellow at the
base."
There is one obvious feature, which I have only recently noticed (and not
mentioned by anyone who responded), that P10 is not completely grown, it is
shorter than P9. This is late for either cachinnans or michahellis to be
completing its primary moult.
On the subject of behaviour, my own observations are that both cachinnans
and michahellis are very aggressive and will charge around in water
threatening other gulls. A question that our European friends might pick up
is - are these forms only aggressive when they are surrounded by other
species, or are they also aggressive when they are "at home" amongst their
own?
Thank you to everybody who responded, it has been useful.
Dick Newell
[ << | >> | ^^ ]
Subject: Re: Elegant Terns in Europe??
From: Alvaro Jaramillo <alvaro(AT)SIRIUS.COM>
Date: 5 Mar 2001 12:37am
At 10:00 PM 2/27/01 -0500, Margie Wilkinson wrote:
>In response to the query:
> > - I found a reference to online pics of the FL bird, but without a URL and
> > I failed to find them using the classical search engines: does anybody
> know?
>
>Pictures of the FL Elegant Tern seen 12/2/00 at Fort DeSoto Park, Pinellas
>County, are online at
>http://home.earthlink.net/~bonniedabird/elegant_tern.htm
>
>The tern was identified by Lyn Atherton, who determined that it was in its
>first
>year and thus not the same bird that spent several weeks at Honeymoon
>Island SRA
>in fall 1999.
Its very difficult to assess a couple of pictures, of a bird at an odd
angle over the Internet so please take my comments with a huge grain of
salt. In any case, from what is presented on this web page the bird does
not look like an Elegant Tern to me. In fact its a better fit for a Cayenne
Tern. This is based on the bill colour as well as the long-legged, stocky
and shorter winged structure of this bird. What are the birds its with?
Looks like some smaller birds towards the left (Common Terns?) and some
larger ones to the right (Sandwich?), and the Elegant Tern looks larger
than both. Is this a correct assessment?
regards,
Alvaro
Alvaro Jaramillo
Biologist
San Francisco Bay Bird Observatory
P.O. Box 247
Alviso, CA 95002
(408)-946-6548
http://www.sfbbo.org/
Home of the California Fall Challenge!!
alvaro(AT)sirius.com
Birds of Chile and
New World Blackbirds at : http://www.sirius.com/~alvaro
[ << | >> | ^^ ]
Subject: Re: Elegant Terns in Europe??
From: Alvaro Jaramillo <alvaro(AT)SIRIUS.COM>
Date: 5 Mar 2001 12:37am
At 06:12 PM 2/27/01 +0100, Laurent Raty wrote:
Birders,
I have been away while all this discussion was going on so I apologize if
my comments have already been dealt with and I missed it.
>* RANGE OF ELEGANT TERN
>
>Elegant migrates south, to winter along the Pacific coasts of America,
>mainly in Peru and N Chile, but a few birds can remain north, as far as
>California, and others reach as far south as C Chile. I could not trace any
>record from S Chile - all maps I have seen showed a winter range extending S
>at most to the latitude of Santiago de Chili (i.e., still more than 2,000 km
>N of the Strait of Magellan). The species is unrecorded from Argentina.
This is not quite right. The species is downright common in central Chile
remaining common at least as far south as Puerto Saavedra at 39 degrees
south (Santiago is at 33 degrees). My southernmost records were of multiple
individuals at Puerto Montt at 41.5 degrees south and I am sure that they
get further south than this. Like Peruvian Pelicans and Franklin's Gulls
which share a similar general latitudinal distribution in Chile its likely
that some wander as far south as the Straits of Magellan or close to it
sometimes. My impression is that the wintering distribution moves south as
the winter deepens, so birds are wintering further south in December than
they are in November etc.
Interchange between Pacific Coast and Atlantic Coast in southern
South America is probably more common than is currently known. Remember
that the number of observers down there is very small and that visiting
birders go to the same places over and over again, they do not explore.
Juan Mazar Barnett has recently found a specimen of Pink-footed Shearwater
from coastal Argentina that was misidentified in the national museum in
Argentina. I have seen a Manx Shearwater in central Chile. There are
breeding populations of both Guanay and Red-legged Cormorants (largely
Pacific coast species) in southern Argentina which likely are recent (in
"biogeographic time") colonizations. More trans ocean wanderers are likely
to be found once more observers are down there looking for this stuff. I
would not be surprised if
>* SO, WHAT IS HAPPENING?
>
>Obviously, we have three possibilities:
>(1) My reasoning is basically wrong. Elegant Terns do cross continents, are
>overlooked inland, are overlooked on the east coast, do cross oceans and can
>spend spring at the latitude of Alaska... Or, alternately, Elegant Terns do
>reach the Strait of Magellan, are overlooked in southern Chile, are
>overlooked in Argentina and in Brazil, do cross oceans and can spend spring
>at the latitude of Alaska...
A note on the pelagic nature of Elegant Tern's migration. If you look at
books on Costa Rican or Panamanian birds it is obvious that the Elegant
Tern is not very common there. In particular, it is rare in Panama. The
suggestion has been made (See Ridgely and Gwynne, A guide to the Birds of
Panama) that their migration through that part of the world is entirely
pelagic. Thus far, this is the most parsimonious answer to explaining why
they are not common in Panama. So I think its a mistake to classify the
Elegant Tern as entirely non-pelagic based on present knowledge. With
regards to inland sightings, I don't think that Laurent noted the Arizona
records but I may be incorrect on this, I think there are at least two
Arizona records. Note also that Royal Terns are coastal terns, but they are
regularly seen inland in Lake Peten Itza in northern Guatemala.
Just a thought here. Apart from the differences in breeding range, and the
fact that Elegant Tern is coastal at all times the Franklin's Gull has a
similar wintering range, migratory path and general distance of migration.
There is nothing really obvious as to why Franklin's Gull should be so
prone to vagrancy but it is. The only aspect of the biology of the
Franklin's Gull that may make it prone to vagrancy is that the species is
entirely migratory and for a gull it is one of the ones with a longer and
trans-equatorial migration. These characteristics are also shared by the
Elegant Tern. Other than the Common and Arctic Terns few terns migrate as
long a distance as does the Elegant Tern, also it appears that most, if not
all, members of the species migrate out of the general breeding area unlike
some terns where a sizeable proportion of the population remains close to
or at latitude where they breed. Elegant Terns are also trans-equatorial
migrants. Finally, other than a few pelagic birds, Elegant Tern is perhaps
the only migratory species which gets hit by the ENSO both in the breeding
and wintering grounds. This likely means that extreme levels of dispersal,
in order to survive these disruptions, occur in this species but I am
hypothesizing to the extreme here.
Have any of the European birds been sound recorded? A good sound recording
of these birds could certainly be analyzed to see how well it compares to
Elegant Tern versus other ID contenders. While calls of some of these
larger terns are similar, they are not identical. Also were close
observations made of displays which could aid in the identification?
cheers,
Alvaro
Alvaro Jaramillo
Biologist
San Francisco Bay Bird Observatory
P.O. Box 247
Alviso, CA 95002
(408)-946-6548
http://www.sfbbo.org/
Home of the California Fall Challenge!!
alvaro(AT)sirius.com
Birds of Chile and
New World Blackbirds at : http://www.sirius.com/~alvaro
[ << | >> | ^^ ]
Subject: Re: Elegant Terns in Europe??
From: Alvaro Jaramillo <alvaro(AT)SIRIUS.COM>
Date: 5 Mar 2001 12:37am
At 05:45 PM 2/27/01 -0800, Don Roberson wrote:
>. Yes, the topic of Lesser Crested was discussed but
>the real problem is separating Elegant Tern from a yellow-billed Sandwich
>Tern. There is a yellow-billed race of Sandwich Tern, S. s. eurygnatha
>(sometimes considered a separate species "Cayenne Tern") which nests on islets
>off Venezuela to Trinidad and winters along the eastern coast of S. America
>south to Argentina. I know rather little about the Cayenne Tern but there is a
>color photo of a breeding colony (in Curacao) in Voous' 1983 "Birds of the
>Neterlands Antilles." Vagrant Cayenne Terns need always to be considered.
Cayenne Terns are breeders in eastern and southern South America. They
breed south to Chubut in Argentine Patagonia and migrate north in the
Austral winter. I am still unclear on the situation in northern South
America and Trinidad/Tobago regarding "intermediate" looking birds between
Sandwich and Cayenne Terns. What I understand is that birds in these areas
may show dark bill bases and this has been interpreted as evidence that the
two forms hybridize. This is of course a possibility but it is unclear if
mixed pairs of known identity are known or not, I would love to learn if
they have. Cayenne Terns in Argentina, well away from areas of potential
hybridization, also may show dark bill bases. So perhaps dark bill bases
have nothing to do with hybridization and are merely a Cayenne Tern trait.
Dark bill bases in Elegant Terns are also of regular occurrence, usually
dark sides to the bill in my experience. But I do agree with Don that
Cayenne Terns should be considered when identifying out of range Elegant
Terns.
Richard Gutierrez wrote:
>Structure of
>Cayenne terns (S.s.eurygnatha) as far as literature says, is not different
>from sandvicensis and bill colour (and size!) is very unlike elegans.
Bill colour in Elegant Terns is highly variable, so there may be overlap
with Cayenne Tern. However, bill structure differs with Elegant having a
longer and thinner bill. Also Cayenne Terns do differ from Sandwich Terns
in size and structure, at least down in Argentina. Here Cayenne Terns are
both larger, longer-legged, thicker-billed and just more robust overall
than Sandwich Terns the few times I saw the two side by side. Apparently
northern South American Cayenne Terns are more similar to Sandwich Terns in
structure, but the southern birds are likely more migratory and therefore
the ones more prone to vagrancy than the northern ones. For more info see:
Jaramillo, A. P. 2000. Punta Rasa, South America's first vagrant trap?
Cotinga 14: 33-38.
regards,
Alvaro
Alvaro Jaramillo
Biologist
San Francisco Bay Bird Observatory
P.O. Box 247
Alviso, CA 95002
(408)-946-6548
http://www.sfbbo.org/
Home of the California Fall Challenge!!
alvaro(AT)sirius.com
Birds of Chile and
New World Blackbirds at : http://www.sirius.com/~alvaro
[ << | >> | ^^ ]
Subject: Re: Elegant Terns in Europe??
From: David Powell <vireo(AT)VIREOS.COM>
Date: 5 Mar 2001 6:18am
I saw this bird at Fort DeSoto. The bill is much more red-orange than the
picture
shows, long, thin, and down-turned. The birds it is with are Forster's Terns
and
I think Sandwich Terns, though the bird at the back that seems to be a Sandwich
is
difficult to be sure of. In size, this bird was slightly larger than Sandwich,
clearly larger than Forsters, and clearly smaller than Royal. Though I have no
experience with Cayenne Tern, there didn't seem to be anything about this bird
that was inappropriate for Elegant Tern.
Dave
Alvaro Jaramillo wrote:
> At 10:00 PM 2/27/01 -0500, Margie Wilkinson wrote:
> >In response to the query:
> > > - I found a reference to online pics of the FL bird, but without a URL
and
> > > I failed to find them using the classical search engines: does anybody
> > know?
> >
> >Pictures of the FL Elegant Tern seen 12/2/00 at Fort DeSoto Park, Pinellas
> >County, are online at
> >http://home.earthlink.net/~bonniedabird/elegant_tern.htm
> >
> >The tern was identified by Lyn Atherton, who determined that it was in its
> >first
> >year and thus not the same bird that spent several weeks at Honeymoon
> >Island SRA
> >in fall 1999.
>
> Its very difficult to assess a couple of pictures, of a bird at an odd
> angle over the Internet so please take my comments with a huge grain of
> salt. In any case, from what is presented on this web page the bird does
> not look like an Elegant Tern to me. In fact its a better fit for a Cayenne
> Tern. This is based on the bill colour as well as the long-legged, stocky
> and shorter winged structure of this bird. What are the birds its with?
> Looks like some smaller birds towards the left (Common Terns?) and some
> larger ones to the right (Sandwich?), and the Elegant Tern looks larger
> than both. Is this a correct assessment?
>
> regards,
>
> Alvaro
--
David Powell
Brandon, FL
vireo(AT)vireos.com
[ << | >> | ^^ ]
Subject: Ruddy Duck
From: paullarkin <paullarkin(AT)PGEN.NET>
Date: 5 Mar 2001 10:18am
What Ho!
Having recently received the Sibley guide from my brother in the USA I note
that there is a reference, and an illustration, of "rare dark Ruddy Duck
adult male". I cannot find any reference to this form anywhere else, the
closest being in Madge & Burn and described as Peruvian Ruddy Duck,
apparently local in South America and unknown in captivity in the UK. Most
of our stock of Ruddy Ducks in the UK are introduced (I say most as one
would assume some could be true vagrants) it was, therefore, a surprise to
find a bird as illustrated in the Sibley guide on my local patch in Kent UK
in 1998. This was originally called (incorrectly) as an Argentinean Blue
Bill but later as a Peruvian Ruddy Duck (mainly because of the extent of the
black "hood" and the bill structure). It mated with Ruddy Ducks to produce
young with varying amounts of black on the head. Can anyone advise on the
following:
1. Is the "rare dark Ruddy Duck" regarded as being the same as Peruvian
Ruddy Duck?
2. If not how often is it recorded in North America and what are it's
distinguishing features from PRD?
3.If it is the same what is it's status in North America?
["I am prepared to consider evidence and accept if it satisfies me" - M.R.
James.]
[ << | >> | ^^ ]
Subject: Re: Elegant Terns, again
From: "Lethaby, Nick" <nlethaby(AT)TI.COM>
Date: 5 Mar 2001 10:45am
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this format, some or all of this message may not be legible.
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Although I think the number of apparent occurrences of Elegant Terns in
Europe is a little surprising, I think the greater number of occurrences
there v. the E. coast of the USA can be explained quite easily.
In NW Europe, any large tern with an orange/red bill is very rare.
Furthermore, the density of birders is much higher in places like the UK and
Belgium. So any such tern is probably going to be seen. In contrast in the
E. USA, Royal Terns are common over much of that area, making detection of
an Elegant much more difficult. This may be analogous to the lack of juv
Red-necked Stints in N. America. These must occur but are finding one in the
millions of Westerns and Semi-palmateds is very difficult.
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[ << | >> | ^^ ]
Subject: Fwd: Emperor Goose molts
From: David Vander Pluym <SCRE(AT)AOL.COM>
Date: 5 Mar 2001 12:15pm
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From: "Shawn Steinberg" <ssteinbe(AT)teleport.com>
To: <SCRE(AT)aol.com>
Subject: Emperor Goose molts
Date: Sun, 4 Mar 2001 22:46:49 -0800
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To whom it may concern
I finally saw a bird that was a candidate for an EMPEROR GOOSE on Sauvie Isl=
and. I am not sure if this is one of the reported hybrids or one of the repo=
rted EMGO's. I have written up a description of the bird.=20
The bill of the bird was short, and pink. I didn't take note of the lower bi=
ll color.
The bird was short and stocky and associated with about 250 Canada Geese, ju=
st off of Reeder Rd.
The bird had a "scaly" appearance - very blue body, as compared to neighbori=
ng Duskies and Western Canadas.
The head that should be a pure white in an adult Emperor Goose had some spec=
kling on the back of the head.
Can someone who is familiar with molts in Emperor Geese comment on this bird=
? I had heard that the speckling on the back of the head indicated that it w=
as more than likely a hybrid as an adult would have a clean white head and n=
eck. In Nat. Geo. 3rd Edition, the comments about the molt from Juvenile to=20=
Adult plumage is WHITE speckling on an otherwise dark head. Can the converse=
be true? Or is this blue/black speckling on a white head, in fact, indicati=
ve of a hybrid bird?
Shawn Steinberg, 17
West Linn, OR (NW Clackamas County)
ssteinbe(AT)teleport.com
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[ << | >> | ^^ ]
Subject: Re: Fwd: Emperor Goose molts
From: "Korpi, Ray" <RKorpi(AT)CLARK.EDU>
Date: 5 Mar 2001 2:26pm
Let me add some info to the attachment. On the Sauvie Island Christmas count
in December, I found an immature Emperor Goose in a flcok of Cackling
Canadas. It looked pretty much as one would expect a young Emperor to look
at that time. Since then, several have seen the bird, and it does not seem
to be molting as one would expect. The dark feathering on the front of the
throat is not filling in as guides suggest it might as the rest of the head
and neck whitens. The back is what one would expect for an Emperor:
blue-grey-slate feathering with black edging, giving a scaled appearance.
The feet are yellowish green, as one would also expect, and the size is
right for an Emperor. The molt of the neck has been weird, though when I
saw it in late January, the bird did have a few dark throat feathers, but
not all the way up the throat. The top of the head and back of the neck
were white, eliminating dark-phased Ross's, and bill proportion eliminated
Blue Goose.
Compounding the problem of finding the bird as it has wintered here has been
the presence of one or two hybrid geese. One of these birds looks
superficially like an Emperor from a distance, but once in a scope or
studied more carefully, the brownish body suggests Canada as some of the
parentage, and orange feet suggest white-fronted as part as well. The bird
has an extensive amount of white on the head, which is why people have been
calling it an Emperor at times.
This may be one of those cases where the best thing for those of us who have
seen the birds is to compare notes and see what's what. Several people have
seen at least two of the three birds in question, and perhaps our
observations over time may help understand some molt occurrences in an
Emperor. I'm interested, as Shawn is, to hear what people might add.
I've cc'd the Oregon Birders on Line group as several of us have discussed
these birds.
RK
Ray Korpi, PhD
Director, Hawkins Computer Lab
English Department
Clark College, Vancouver WA
-----Original Message-----
From: David Vander Pluym [mailto:SCRE(AT)AOL.COM]
Sent: Monday, March 05, 2001 11:14 AM
To: BIRDWG01(AT)LISTSERV.ARIZONA.EDU
Subject: [BIRDWG01] Fwd: Emperor Goose molts
Hi this was sent to me with the request that it be forwarded to this list.
David Vander Pluym
Age 18
Ventura California
[ << | >> | ^^ ]
Subject: Re: Ruddy Duck
From: Malcolm Ogilvie <Malcolm(AT)INDAAL.DEMON.CO.UK>
Date: 5 Mar 2001 2:52pm
In message <002c01c0a599$101a1ce0$5b213c3e@uxledkvk>, paullarkin
<paullarkin(AT)PGEN.NET> writes
>What Ho!
>
>Having recently received the Sibley guide from my brother in the USA I note
>that there is a reference, and an illustration, of "rare dark Ruddy Duck
>adult male". I cannot find any reference to this form anywhere else, the
>closest being in Madge & Burn and described as Peruvian Ruddy Duck,
>apparently local in South America and unknown in captivity in the UK.
I'm not sure of the present-day situation, but the Wildfowl and Wetlands
Trust, Slimbridge, certainly had a pair of Peruvian Ruddy Ducks in the
1980s.
This is the darkest race and occurs from Columbia south to Peru. I
wasn't aware that it had ever occurred in North America, assuming this
is what Sibley is referring to. I've never heard of any dark form of the
North American Ruddy Duck. Palmer doesn't mention anything, but of
course 'The Birds of North America' hasn't published its account yet.
> Most
>of our stock of Ruddy Ducks in the UK are introduced (I say most as one
>would assume some could be true vagrants) it was, therefore, a surprise to
>find a bird as illustrated in the Sibley guide on my local patch in Kent UK
>in 1998. This was originally called (incorrectly) as an Argentinean Blue
>Bill but later as a Peruvian Ruddy Duck (mainly because of the extent of the
>black "hood" and the bill structure). It mated with Ruddy Ducks to produce
>young with varying amounts of black on the head. Can anyone advise on the
>following:
>1. Is the "rare dark Ruddy Duck" regarded as being the same as Peruvian
>Ruddy Duck?
Who can say, without knowing what Sibley was referring to? I suggest you
write to him!
>2. If not how often is it recorded in North America and what are it's
>distinguishing features from PRD?
See above. I'm not aware of any North American record but I guess it is
not impossible. Frank Todd says that they have formerly been present in
North American collections.
>3.If it is the same what is it's status in North America?
>
???
--
Malcolm
[ << | >> | ^^ ]
Subject: Re: Unidentified UK Gull - wrap up
From: Nick Rossiter <nrossiter(AT)SUPANET.COM>
Date: 5 Mar 2001 3:35pm
While not disagreeing with the conclusion that this is probably a 3rd-winter
(3rd calendar year) michahellis -- the mirror on P10 being perhaps the best
indicator of age - there seem to be some puzzling/interesting aspects which
could be considered further.
The bill seems more aberrant than retarded. Does the yellow not first
develop at the base and then gradually extend outwards? To have a yellow
terminal portion with black inside seems a very odd progression. From
studies of Atlantic Yellow-legged Gulls the all-black bills are quite
persistent into the second-winter with a number with only small pale bases
in September of their second calendar year. By April/May (second-summer,
third calendar year) the bare parts become much more yellow with the great
majority having extensive yellow bases to the bills by the latter month.
The massive variation in the rate of moult from bird to bird, as claimed by
some contributors, is certainly correct.
P10 is indeed slightly shorter than P9 on the bird in question. The
Atlantic birds often have P9 and P10 of similar length but this seems rather
unusual. When the PA mystery gull was around, I raised the question then of
moult timings in adult michahellis. A significant minority (40%) of the Gran
Canaria adults in the last week of September 2000 had shed all their old
primaries and were still growing P8-P10 with P8 almost fully grown, P9 half
grown and P10 just emerging. Does anyone know how long it will take for the
wing to be complete?
Another interesting feature is the extensive amount of black on P4 --
perhaps not unusual for Mediterranean YLG -- but much more than is found on
Atlantic birds (other than in the Azores).
I have some photographs and notes on second-year birds at
http://www.nrossiter.supanet.com/ylg/ which while they apply to Atlantic
birds are presumably also relevant for Mediterranean ones. If there are some
differences, I'd be very happy to hear of them. One of the second-year
photos includes an adult with the moult condition described above. I'm still
working on third-years!
Regards ... Nick Rossiter
[ << | >> | ^^ ]
Subject: The Spanish Elegant Tern online
From: Ricard Gutierrez <GUTARB(AT)terra.es>
Date: 5 Mar 2001 4:22pm
Hello:
After all the interesting comments heard on the Elegant subject, I've
thought that I could add something more: the Spanish bird photos and some
comments.
I've scanned two of the better pictures of the 1993 bird and put them in the
RBS (Rare Birds in Spain) web site http://www.terra.es/personal3/gutarb
together with a few comments on the bird.
This individual is accepted and there is even an article published in Dutch
Birding. I think, however, it would be interesting to hear your comments on
this individual (if any).
It arrived following a migrant party of Sandwich Terns (S.sandvicensis).
Yours
Ricard Gutiérrez
CR/SEO
6.3.2001
[ << | >> | ^^ ]
Subject: Re: Ruddy Duck
From: Joseph Morlan <jmorlan(AT)CCSF.ORG>
Date: 5 Mar 2001 5:42pm
On Mon, 5 Mar 2001 21:38:15 +0000, Malcolm Ogilvie
<Malcolm(AT)INDAAL.DEMON.CO.UK> wrote:
>This is the darkest race and occurs from Columbia south to Peru. I
>wasn't aware that it had ever occurred in North America, assuming this
>is what Sibley is referring to. I've never heard of any dark form of the
>North American Ruddy Duck. Palmer doesn't mention anything, but of
>course 'The Birds of North America' hasn't published its account yet.
There is a photograph of this type taken by Don DesJardin in Ventura
County, California, posted on my web site. It was featured as one of
my August 1998 "Mystery birds." At the time I speculated as far as I
could, but reached no firm conclusion.
See: http://fog.ccsf.cc.ca.us/~jmorlan/aug.htm for my thoughts and the
photo.
When I opened "Sibley" and saw his dark-headed Ruddy illustrated I
wondered to myself if Sibley's treatment could be based at least in
part on the photo on my web site. I also am unaware of any published
accounts of dark-headed Ruddy Ducks in North America, other than
what's on my web site.
--
Joseph Morlan, Pacifica, CA 94044: mailto:jmorlan(AT)ccsf.org
California Birding; Mystery Birds: http://fog.ccsf.org/~jmorlan/
California Bird Records Committee: http://www.wfo-cbrc.org/cbrc/
[ << | >> | ^^ ]
Subject: Re: Ruddy Duck
From: Rich Hoyer <calliope(AT)THERIVER.COM>
Date: 5 Mar 2001 6:50pm
Dear ID People,
I found such a Ruddy Duck at Willcox, Arizona in June 1994, and called it a
melanistic bird. (It was independently found by another birder and called in
as a Masked Duck. Oops.) This bird was subsequently seen by several other
birders. See the Southwest Region report by Gary H. Rosenberg, Chris D.
Benesh, and David Stejskal in Field Notes Vol. 48 No. 5, p. 971. It appears
as a "Special Attention" note, and they give a very good description of it.
I did not take notes at the time, only noting it as "interesting".
Good Birding,
Rich
---
Rich Hoyer
Tucson, Arizona
Field Leader for
WINGS, Inc.
http://www.wingsbirds.com
---
Note: I will be gone March 21st- 26th
[ << | >> | ^^ ]
Subject: Re: Ruddy Duck
From: Dave Sibley <dsibley(AT)SHORE.NET>
Date: 5 Mar 2001 7:33pm
Hi All,
Regarding the dark male Ruddy Duck in my guide: I included that
illustration because of the bird that was seen in Willcox Arizona in
1994 (thanks to Rich Hoyer for details of that) and the similar bird
later in Ventura, California (thanks to Joe Morlan for posting photos
and details of that bird). I seem to recall at least one other
individual reported somewhere else in the US, but can't remember the
details. It would be interesting to hear of other records.
I did not really investigate to try to figure out whether these were
Peruvian Ruddy Ducks or some other species, it seemed more likely the
birds were simply melanistic Northern Ruddys. I jumped to this
conclusion after seeing several birds around the US with varying small
amounts of black across the white cheeks and throat, up to about 20% on
one bird at Cape May, NJ. Also, it was obvious that Peruvian Ruddy and
other ID contenders were simply very unlikely to occur, except as rare
escapes.
Two final comments - The color difference in the rufous body of the two
male Ruddy Ducks in my guide is the result of painting the dark-headed
male at a late date without referring to the original art for the
typical male, which was painted about five years earlier. And my main
rationale for including such a rare variant in the guide was that I knew
the two birds mentioned above had both been identified as Masked Duck by
a few observers and caused some confusion, which could be easily
prevented.
David Sibley
Concord, MA
david(AT)sibleyart.com
[ << | >> | ^^ ]
Subject: Re: Ruddy Duck
From: Steven Mlodinow <SGMlod(AT)AOL.COM>
Date: 5 Mar 2001 9:50pm
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Greetings All
I once had a male Ruddy Duck with an all black or blackish head at the Salton
Sea. I remember wondering if it could be an escapee, but never did much more
with it.
Cheers
SteveMlodinow
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[ << | >> | ^^ ]
Subject: Dark-headed Oxyura
From: Andrew Harrop <andrew.harrop(AT)VIRGIN.NET>
Date: 5 Mar 2001 10:27pm
Dear All,
Here at Rutland Water, UK, I observed a dark-headed male Oxyura on 30/4/99.
The bird resembled a male Ruddy Duck (jamaicensis), but its head was
entirely black and the body tones appeared duller; the bill appeared
slightly slimmer and duller; the nail was dark.
It seemed unlikely to be an escaped Peruvian Ruddy Duck (O.j.ferruginea)
since this should be larger and brighter with a larger, broader bill. Maccoa
Duck (O.maccoa) is also larger, and has a whitish nail.
I was left with the possibility that it might be either an escaped Blue-bill
(O.australis or vittata - photos and drawings of australis seem quite a good
match, though I'm not sure about the nail), or an aberrant Ruddy.
To put this into context, there has been at least one male 'Ruddy' in the
area in recent years which has shown dark markings on the white cheek
similar to those of O.j.andina: could these birds be a very rare variant
second calendar-year plumage of jamaicensis?
Andrew Harrop
andrew.harrop(AT)virgin.net
[ << | >> | ^^ ]
Subject: Re: Dark-headed Oxyura
From: Alvaro Jaramillo <alvaro(AT)SIRIUS.COM>
Date: 6 Mar 2001 12:49am
At 06:31 AM 3/6/01 +0100, Andrew Harrop wrote:
>Dear All,
>Here at Rutland Water, UK, I observed a dark-headed male Oxyura on 30/4/99.
>The bird resembled a male Ruddy Duck (jamaicensis), but its head was
>entirely black and the body tones appeared duller; the bill appeared
>slightly slimmer and duller; the nail was dark.
>It seemed unlikely to be an escaped Peruvian Ruddy Duck (O.j.ferruginea)
>since this should be larger and brighter with a larger, broader bill.
Birders,
Just a couple of points. First of all the systematics of the Ruddy Duck
are still in a muddle. The name Peruvian Ruddy Duck is used but probably
not as frequently as Andean Duck for the South American birds. Two taxa
breed in South America, the Colombian form (andina) and the more southern
form (ferruginea). Some lump all of these things in Ruddy Duck and others
split out the Andean Duck as a separate species, which then includes andina
as a subspecies. The problem is that andina is variable in its face
pattern, some having white on the cheek, others partially so and then
others none. This form has been treated as intermediate between Ruddy and
Andean Ducks even though the nearest breeding Ruddys are a heck of a long
way away (Cuba and Mexico). My opinion is that Andean Duck is a valid
species, particularly due to differences in female plumage, male plumage,
structure, ecology etc. Escaped Andean Duck males will be extremely
difficult to differentiate from dark headed Ruddy Ducks but size and
structure may help. Andean Ducks are noticeably larger than Ruddy Ducks
being about 20% larger in mass. Also they have relatively longer bills and
longer tails while having shorter wings. Furthermore the undertail coverts
of the Andean Duck appear to be rusty rather than being whitish, but this
feature needs more study.
If you want to read up on the Colombian population with variable cheeks:
Fjeldsa, J. 1986. Color variation in the Ruddy Duck (Oxyura jamaicensis
andina). Wilson Bull. 98: 592 - 594
The fact that evidence is emerging that northern Ruddy Ducks sometimes have
dark heads is interesting. Variability in head patterns may just be typical
of this group. It may also suggest that the dark head is an ancestral
character that birds sometimes revert to.
cheers,
Alvaro
Alvaro Jaramillo
Biologist
San Francisco Bay Bird Observatory
P.O. Box 247
Alviso, CA 95002
(408)-946-6548
http://www.sfbbo.org/
Home of the California Fall Challenge!!
alvaro(AT)sirius.com
Birds of Chile and
New World Blackbirds at : http://www.sirius.com/~alvaro
[ << | >> | ^^ ]
Subject: Dark-headed Oxyuras
From: Peter Adriaens <Peter.Adriaens(AT)KENDER-THIJSSEN.BE>
Date: 6 Mar 2001 1:58am
Hi all,
a completely blackish head can occasionally be seen in White-headed Duck
(what's in a name...) [Oxyura leucocephala], which is closely related to
Ruddy Duck. I have seen such birds in southern Spain (two in a flock of 400
White-headed Ducks). I think they are generally believed to be dark
immatures.
Best regards,
Peter Adriaens
BELGIUM
[ << | >> | ^^ ]
Subject: A strange Saxicola
From: Ugo Mellone <ugomellone(AT)LIBERO.IT>
Date: 6 Mar 2001 12:23pm
Dear birders,
please, have a look at
http://digilander.iol.it/wildphoto/mystery.htm
What do you think about it?
Regards,
Ugo Mellone - Italy
[ << | >> | ^^ ]
Subject: Re: The Spanish Elegant Tern online
From: Phil Pickering <philliplc(AT)HARBORSIDE.COM>
Date: 6 Mar 2001 4:01pm
This is certainly another "grain of salt" commentary, since I have
comparatively little real life experience with either Sandwich or
Elegant Terns. However, I have wasted quite a bit of free time
recently trying to assess the structural features and color of birds
in photos. Because of this I can understand Paul Lehman's comment
on having a gut feeling that something seems wrong with a particular
photo or photos.
I get that feeling very strongly about the Spanish Elegant at -
http://www.terra.es/personal3/gutarb/arbsi009.htm
To me, this bird actually seems quite close structurally to the
Sandwich Terns it's with. It seems very close in overall size
and proportions, and also in posture. In particular, the length
of the bill seems very close to the nearest Sandwich facing
the same directing (left edge of first photo) and proportionately
too short for Elegant in my experience. Also, the base of the
bill seems too thin in proportion to the head for Elegant, and
thus the bill doesn't seem to taper enough (although it does
seem slightly more downcurved than Sandwich).
The description states that the bill is orange, but it seems yellowish-
orange at best to me. The color in the scans seems to be balanced
pretty well, so I don't think the photos are all that misleading in this
respect. Can an Elegant approaching complete breeding-plumage
(nearly complete black on forehead, no apparent duskiness in
primaries) really have a bill this yellowish? My experience with
Elegants is all in fall. At that time adults have bills that are much
more orange-red than this. I think even juveniles show more orange
than is apparent here, at least at the bill base.
The differences between this bird and the Sandwich Terns noted
in the description seem slight at best, and I think a true Elegant
would stand out more in this crowd. Perhaps what was being
observed and noted here are subtle differences between European
Sandwich and Cayenne rather than Sandwich and Elegant? (just
speculation to throw out, since I've never even seen a photo of
Cayenne).
In my opinion, the above comments might also apply to the
Florida bird at -
http://home.earthlink.net/~bonniedabird/elegant_tern.htm
Just my impressions, but the bill also seems somewhat short and
blunt, and the bill base seems thin here for Elegant. The head seems
a bit large in proportion to the smallish body. Elegants strike me as
a bit chunkier-bodied than this bird.
Because I don't have that much experience with the species involved,
my impressions may not mean much in this situation. I would
comment, however, that when you look at a lot of any one species
over a period of time, subtle but distinctive jizz-related features that
aren't obvious to someone without similar experience get burned
into your brain, and it becomes possible to recognize when they are
there (or when they aren't) in most photos. I don't think enough
emphasis can be placed on the fact that respected California birders
with an exceptional amount of experience with Elegants are sensing
that something is wrong in at least some of the photos of the
European records.
Phil Pickering
Lincoln City, Oregon
philliplc(AT)harborside.com
[ << | >> | ^^ ]
Subject: Fwd: Ruddy Ducks
From: Alvaro Jaramillo <alvaro(AT)SIRIUS.COM>
Date: 7 Mar 2001 12:42am
Birders,
A note from Tom Schulenberg on Ruddy Ducks:
>Alvaro,
>
> I'm not 'on' ID-Frontiers, but you might want to post this, or
> follow up on it: Palmer (1976, Handbook of North American birds, volume
> 3, page 502) says:
>
>"Notes As the above feathering [adult male alternate plumage] grows in
>spring, quite commonly [!] there appear few to many black feathers (like
>crown) in white of cheeks and across the chin, occasionally so many as to
>form patches (cheeks nearly all black or patchy in specimens from as far
>n. as Kindersley, Sask.); evidently these feathers soon fall out (cheeks
>become all white)."
>
> News to me, but there's a lot that I miss.
>
> Was there a volume of Ridgway that covered waterfowl? -- that
> would be another source to check.
>
>Best wishes,
>
>
>tss
>
>
>
>****************************************
>Thomas S. Schulenberg
>Environmental and Conservation Programs
>Field Museum of Natural History
>1400 S. Lake Shore Drive
>Chicago IL 60605
>
>voice: 312.665.7439
>fax: 312.665.7440
>email: tschulenberg(AT)fmnh.org
>****************************************
>
Alvaro Jaramillo
Biologist
San Francisco Bay Bird Observatory
P.O. Box 247
Alviso, CA 95002
(408)-946-6548
http://www.sfbbo.org/
Home of the California Fall Challenge!!
alvaro(AT)sirius.com
Birds of Chile and
New World Blackbirds at : http://www.sirius.com/~alvaro
[ << | >> | ^^ ]
Subject: Re: A strange Saxicola
From: Eran Tomer <etomer(AT)EMORY.EDU>
Date: 7 Mar 2001 7:22am
Ugo,
On several counts, this is distinctly a Stonechat and not a bunting. The
yellowish underparts are probably not due to pollen but to fresh plumage
(buffy) in warm light. This is supported by the overall appearance, which
is lighter than worn plumaged birds (spring). It is hard to tell from the
photo just how yellow this bird was. If it was yellow enough to recall a
bunting, a color abnormality may also be suspect, especially since the
photo seems to show a dark breast, which is unusual.
Best regards
- Eran Tomer
Atlanta, Georgia, USA
etomer(AT)emory.edu
[ << | >> | ^^ ]
Subject: Re: The Spanish Elegant Tern online
From: norman van swelm <Norman.vanswelm(AT)WXS.NL>
Date: 7 Mar 2001 8:44am
Phil Pickering wrote: >observed and noted here are subtle differences
between European
>Sandwich and Cayenne rather than Sandwich and Elegant? (just
>speculation to throw out, since I've never even seen a photo of
>Cayenne).
The bill colour of Cayenne is lemon yellow lacking any orange unlike Lesser
Crested, Elegant and RoyalTern.
Norman
[ << | >> | ^^ ]
Subject: R: Re: A strange Saxicola
From: Ugo Mellone <ugomellone(AT)LIBERO.IT>
Date: 7 Mar 2001 9:56am
Eran Tomer <etomer(AT)EMORY.EDU> wrote:
>The
>yellowish underparts are probably not due to pollen but to fresh plumage
>(buffy) in warm light. This is supported by the overall appearance, which
>is lighter than worn plumaged birds (spring). It is hard to tell from the
>photo just how yellow this bird was. If it was yellow enough to recall a
>bunting, a color abnormality may also be suspect, especially since the
>photo seems to show a dark breast, which is unusual.
It isn't a trick of light: also in the field the bird appeared very yellow.
Ciao, Ugo
[ << | >> | ^^ ]
Subject: Re: The Spanish Elegant Tern online
From: Florida Nature Tours <fnt(AT)GDI.NET>
Date: 7 Mar 2001 10:34am
norman van swelm wrote:
>
> Phil Pickering wrote: >observed and noted here are subtle differences
> between European
> >Sandwich and Cayenne rather than Sandwich and Elegant? (just
> >speculation to throw out, since I've never even seen a photo of
> >Cayenne).
>
> The bill colour of Cayenne is lemon yellow lacking any orange unlike Lesser
> Crested, Elegant and RoyalTern.
> Norman
Norman & all:
I think that I've followed this thread from the beginning, but if I am
adding
nothing new, please accept my apologies. When I went to The Netherlands
Antilles
in the early eighties I had borrowed from Sandy Sprunt his old 1955
copy of
K.H. Voous "Birds of the Netherlands Antilles". Upon my arrival I was
pleasantly
surprised to learn that Dr. Voous had completely revised his book in
1983. The
first plate in the book is a color photograph of many birds in a
Yellow-billed
Sandwich tern Colony. A quick look at the dust jacket reveals the fact
that the
plate is only 1/3rd of the whole photo which is used for the entire
dust jacket.
The photo & my notes agree with you Norman, as to bill color. But I
think that
we need to take note of what Prof. Voose has to say on the top of page
126: "In
most South Caribbean breeding birds, known as Yellow-billed Sandwich or
Cayenne
Tern, bill is straw-yellow, exceptionally orange, in others yellowish
marked
with variable amount of black, particularly at base of bill; in still
others
black predominates and even whole bill may be black with only tip
yellow".
Food for thought!
Wes Biggs
Florida Nature Tours, Orlando 407/363-1360 fnt(AT)gdi.net
http://www.floridanaturetours.com ABA sponsored
[ << | >> | ^^ ]
Subject: Black-backed robins
From: Ian Mclaren <iamclar(AT)is.dal.ca>
Date: 7 Mar 2001 10:39am
All:
There has been little response to my attenuated thread on "Black-
backed" or "Newfoundland" robins. A few mentioned reports from
their areas (NJ, MI, PA), but not from states where they have not
hitherto been known.
Ron Pittiway's thoughtful comments nevertheless may miss the
points I had attempted to make. I was of course aware of the
views of Godfrey and others on the distribution of _T.
migratorius nigridius_. Godfrey essentially follows the the 1957
AOU Checklist. They are most liberal in including essentially the
whole of the "Labrador Peninsula" (sensu Todd 1963) north from L.
Mistassini (near S James Bay across to St. Pierre et Miquelon and
NF. I also fully appreciate the nature of clinal variation, but
in these surely there should be a core or terminal area where a
reasonable proportion of birds can be assigned to a named taxon.
Todd (1957) himself restricted the name to a range where blackish
birds were "predominant in the population," viz. the coast of
Labrador and in the island of NF. His evidence for "predominant"
in his descriptions of series, however, leave one wondering. E.g.
From NF, "nine males as laid out show a complete gradation from a
gray-backed to a decidely (but not perfectly) black-backed bird,"
and "it is possible to pick out individual specimens from our
Hudson Bay series that show a similar gradation, but none of
these show thesame extreme of blackness . . ." Bruce Mactavish,
on the other hand, feels that at most 20% of NF robins (the "real
bucks?") are distigushable from other eastern robins even during
the breeding season. And Todd also comments on "specimens, more
or less black-backed, from Churchill, Great Slave Lake, Aklavik,
and central Alberta."
So, my question is: where if anywhere do breeding black-backed
males predominate, and possibly deserve name-bearing? I suggested
the Ungava Bay watershed. Todd's map of breeding localities shows
really only four sites in this area, where he thought the birds
were nominally _T. m. migratorius_, but where I saw what I
thought were "blacked-backed robins" in 1951. I'll copy this
message Michel Gosselin at Nat. Mus. of Canada; he may have some
insights from any subsequent collection from that area.
For birders on robin migration routes possibly across much of the
continent, the best one might be able to say is that a black-
backed robin is from "somewhere up there."
Cheers, Ian M.
Ian A. McLaren
Biology Department phone: (902) 494-2565 (W)
Dalhousie University (902) 429-7024 (H)
Halifax, NS B3H 4J1 Fax: (902) 494-3736
[ << | >> | ^^ ]
Subject: Steller's/Blue Jay
From: Calvin Gehlen <calvin(AT)INISYSTEMS.COM>
Date: 7 Mar 2001 10:53am
Hi All,
I'm seeking opinions on what is presumed to be the first record in British
Columbia of a Steller's Jay / Blue Jay Hybrid. There are two photos here:
http://www.members.home.net/gobirding/page8.html
The pictures come to me third hand and I'm still seeking details on the
exact location of the bird. The photos were taken on March 4th, 2001. The
Vancouver Island resident who took the photos had a Blue Jay visiting his
feeder in a previous year.
The only other known similar record is of a bird in Osoyoos, BC in 1990 that
was determined to be a leucistic Steller's Jay.
Your thoughts on this bird are appreciated.
Happy Birding,
Calvin Gehlen
calvin(AT)gobirding.com
Vancouver, BC
It's time to GoBirding at www.gobirding.com
[ << | >> | ^^ ]
Subject: House Martin hybrids
From: Peter Wilkinson <pcwilkinson(AT)clara.co.uk>
Date: 7 Mar 2001 2:00pm
Hi All,
I know that House Martin (Delichon urbica) x Barn Swallow (Hirundo
rustica) hybrids are encountered fairly regularly and indeed are a
confusion possibility for Red-rumped Swallow (Hirundo daurica). I have
seen photographs but have not seen one in the flesh. Does anyone,
however, know of any reference to the possibility of House Martin x Sand
Martin (Riparia riparia) hybrids?
The reason I ask is that last week my wife and I were in the Algarve. At
Quinta do Lago I watched a bird at quite close range (about 20 metres at
its closest)among a large flock of feeding hirundines (almost entirely
Barn Swallow and House Martins, but with at least two Sand Martins)
which essentially showed features of both species but none of those
usually associated with House Martin x Barn Swallow. Basically the
upperparts were blue/black mantle, brown wings, light coffee coloured
rump, and dark tail with no marked forking; the underparts were
off-white chin, brown upper breast band, off white breast and belly.
Because of the melee of birds I kept losing it but usually picked it up
again because of the contrast between the mantle and the wings, which
was quite unlike any hirundine I have seen. Because of the very strong
wind, conditions were not ideal for observing it, but with luck it will
have been seen as well by a couple of birders who arrived as we were
leaving, one of whom I know caught at least a glimpse of it while we
were telling them about it.
Any thoughts gratefully received.
Peter Wilkinson
Wheathampstead, Herts, England
pcwilkinson(AT)clara.co.uk
[ << | >> | ^^ ]
Subject: Re: Black-backed Robins
From: Dave Sibley <dsibley(AT)SHORE.NET>
Date: 7 Mar 2001 3:27pm
My knowledge of "Black-backed" Robins comes mainly from Cape May, NJ,
where I have identified scattered individuals and up to three together
among the large winter robin flocks, mainly Nov-Feb. While extreme
individuals are strikingly colored and at first I was excited about
searching for this "subspecies", over time I realized that the black
back is simply one indication of an overall darkness. The birds with
black backs also have reduced white on the throat and facial markings,
unusually dark rufous underparts, and darker gray upperparts in general.
I also saw the complete range of variation that has been mentioned by
Ian McLaren and Ron Pittaway, and was forced to make subjective
decisions about which birds were dark enough to be "black-backed". I
never noticed any tendency for the dark birds to occur together or to
occur at a particular time of year, they always mixed with large numbers
of normal birds. Then I noticed considerable variation among the small
local breeding population, and even though none qualified as
"Black-backed" I began to wonder if the apparent "winter visitor" status
of black-backed birds was simply because that was the only season when I
was able to study hundreds of robins.
R. M. Mengel, in "The Birds of Kentucky" 1965, AOU Monograph 3 has
published some actual research that hasn't been quoted in previous
posts. He writes about the Labrador-Newfoundland population: "it is my
present opinion that these birds represent the extreme expression of a
general tendency to rich coloration in the extreme north; one found
also, incidentally, in an appreciable percentage of Appalachian birds".
Then lists three specimens from Kentucky, including one taken on Sep 24,
before migrants would be expected, and continues "Even if *nigrideus*
proves valid, I have seen so many dark-backed specimens taken in the
eastern United States in the breeding season that I think it best not to
include the race in this [Kentucky] list on the basis of three
specimens".
So this doesn't address the question of where the "core range" of
"Black-backed" robins might be, it might lead one to hypothesize that
there is no core range. It does help to answer Ian's question number 2.
Black-backed robins may originate from virtually anywhere in eastern
North America, (and perhaps western North America as well?), so timing
and locations of sightings on the wintering grounds will give no clue to
any core range of "Black-backed" robins.
David Sibley
Concord, MA
David(AT)sibleyart.com
[ << | >> | ^^ ]
Subject: Re: The Spanish Elegant Tern online
From: norman van swelm <Norman.vanswelm(AT)WXS.NL>
Date: 7 Mar 2001 3:56pm
>norman van swelm wrote:
>>
>> The bill colour of Cayenne is lemon yellow lacking any orange unlike
Lesser
>> Crested, Elegant and RoyalTern.:
>
Wes Biggs wrote:
>I was pleasantly surprised to learn that Dr. Voous had completely revised
his book in
>1983. The first plate in the book is a color photograph of many birds in a
>Yellow-billed Sandwich tern Colony. A quick look at the dust jacket reveals
the fact
>that the plate is only 1/3rd of the whole photo which is used for the
entire
>dust jacket.The photo & my notes agree with you Norman, as to bill color.
But I
>think that we need to take note of what Prof. Voous has to say on the top
of page
>126: "In most South Caribbean breeding birds, known as Yellow-billed
Sandwich or
>Cayenne Tern, bill is straw-yellow, exceptionally orange, in others
yellowish
>marked with variable amount of black, particularly at base of bill; in
still
>others black predominates and even whole bill may be black with only tip
>yellow".
> Food for thought!
Indeed! However on all photo's I have seen of unusual Sandwich Tern like
birds seen in Europe (UK, Denmark, France, Spain) all have orange bills
unlike any individual in any photo I have seen of Cayenne's, and I have seen
very many of them (alas no personal experience)! I speculate (sic!) that an
orange-billed bird in the Dutch Antilles could be an Elegant Tern just as
well and that such observations deserve a second look. As for the
yellow-tipped black-billed Cayenne's seen in Europe you had better consult
an expert.
Norman
[ << | >> | ^^ ]
Subject: Re: Black-backed Robins
From: Ian Mclaren <iamclar(AT)is.dal.ca>
Date: 8 Mar 2001 9:53am
All:
David Sibley has offered what I think is a very sensible last word on this
subject. Let's look for another "subspecies" conundrum.
Cheers, Ian M.
Ian A. McLaren
Biology Department phone: (902) 494-2565 (W)
Dalhousie University (902) 429-7024 (H)
Halifax, NS B3H 4J1 Fax: (902) 494-3736
[ << | >> | ^^ ]
Subject: FW: [BIRDWG05] AZ sapsuckers
From: Rich Hoyer <calliope(AT)THERIVER.COM>
Date: 10 Mar 2001 5:54pm
Dear IDers,
This message stems from a discussion recently on birdwg05 (the Arizona/New
Mexico birding e-mail list), especially in regard to a sapsucker that has
been wintering in NE Tucson. In my opinion, the bird falls right on the line
between a very red Red-naped X Red-breasted (daggetti) and a very strongly
marked Red-breasted (daggetti). Some people feel that this bird is as
Red-breasted as they get in Arizona. We have been "plagued" by more obvious
hybrids (or perhaps by reports of such birds as Red-breasted) in recent
winters, as we seem to be in the heart of their wintering range here.
It would be nice if some of you with experience with Sphyrapicus ruber
daggetti and hybrids could look at these photos and comment, especially in
regards to the one photographed by Mark Stevenson.
More photographs of an apparent hybrid can be found at
http://www.gis.net/~dhsmall/red-breasted_Sapsucker.htm. This bird has been
wintering at the Pinal Air Park Pecan Grove in N-C Pima County, Arizona this
winter.
Happy Browsing,
Rich
---
Note: I will be gone March 21st- 26th
----------
> From: "Roy M. Jones" <barbet(AT)PRIMENET.COM>
> Reply-To: "Roy M. Jones" <barbet(AT)PRIMENET.COM>
> Date: Sat, 10 Mar 2001 09:27:43 -0700
> To: BIRDWG05(AT)LISTSERV.ARIZONA.EDU
> Subject: [BIRDWG05] AZ sapsuckers
>
> I put a couple of photos from the recent Red-breasted/Red-naped sapsucker
> discussion on my website. Please check them out and share your opinions on
> sapsucker identification. The two birds included are the Woodland Road bird
> (Mark Stevenson) from Tucson, and the Coon Bluff bird (Andy Spencer) from
> the phoenix area. I also added a few of the comments to date. Mark pointed
> us to a great article from the Auk (January 1985. Vol. 102, No. 1) on the
> subject, I suggest it to anyone interested in the topic. It's a great study
> of what makes birds look the way they do (feather color in the form of
> pigment) and how feather wear and molt can be used to help identify
> troublesome birds, like possible hybrids. Kenn gave a good synopsis of the
> situation in Arizona with so many odd looking sapsuckers. After seeing these
> photos, I feel terrible about not having seen either of these birds. I've
> got to stop working, get away from this stupid machine, and go birding.
> Later!
>
> http://www.primenet.com/~barbet/sapsuckers.htm
>
> Roy M. Jones
> 2237 N. Sunset Dr.
> Tempe, AZ 85281
> http://www.primenet.com/~barbet/
>
[ << | >> | ^^ ]
Subject: Re: AZ sapsuckers
From: Rich Hoyer <calliope(AT)THERIVER.COM>
Date: 10 Mar 2001 10:40pm
Dear People,
It appears that David Small's web page doesn't have his sapsucker photos up
any more. Roy Jones' link, repeated below, still works.
Rich
http://www.primenet.com/~barbet/sapsuckers.htm
---
Note: I will be gone March 21st- 26th
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