Subject: [Tweeters] Whooper vs. Bewick's
Date: Jan 8 20:38:08 2007
From: SCOTT WARNER - swarner28 at msn.com


I had the great pleasure of seeing the "Whooper" south of Conway on Sunday. However, at the time, I was not aware of the Bewick's possibility mentioned by David Hayden. Now that I have looked at the text and pictures of both "species" in "Master Guide to Birding" (MGB) put out by The Audubon Society in 1983, I cannot say with any certainty that the bird was not a Bewick's instead of a Whooper. I didn't hear it's call, so I can't use that for identification. MGB states that the Bewick's is "vagrant to Washington, Oregon, and California", and shows a picture of a Bewick's with less yellow in the bill than for a Whooper, but remarkably similar to the pictures posted by the Sullivans. MGB states for the Whooper that "the validity of most sightings outside of Alaska is subject to doubt", and does not mention the possibility that it might be a rare vagrant to the northwest Pacific Coast.

MGB states that the Whooper "often holds it's head forward in a curved or kinked posture, as does the Trumpeter Swan". Several of the Sullivans' pictures show such a curve, but in at least one picture the neck is straight. The picture of the Bewick's in MGB shows the yellow extending all the way to the eye. I didn't check that feature out on Sunday because at the time I didn't know what I should be concentrating on; and I can't tell for sure from the Sullivans' pictures.

>From my limited experience of trying to distinguish a Tundra from a Trumpeter, from anything other than sound or the occasional yellow spot on the Tundra bill, I would not want to use the size of the bird or the curve of the neck as definitive identifying characteristics. So, what to do? I can go to my "Birds of North America" by Kaufman, which doesn't recognize the existence of a Bewick's, and easily conclude that it was definitely a Whooper, because it's the only swan shown with a yellow bill.

Here are other questions to ponder. If, as stated in MGB, the Bewick's is an East Asian subspecies of the Tundra, might not the Whooper be an East Asian subspecies of the Trumpeter? Might the Bewick's and the Whooper be the same species? Or, for that matter, might the Tundra be a subspecies of the Trumpeter, in much the same manner that the Cackling Goose has always been considered a subspecies of Canada Goose until very recently? Are the two "species" capable of interbreeding successfully? Can anyone shed any light on these issues?

Scott Warner
Brier, WA
swarner28 at msn.com<mailto:swarner28 at msn.com>