Tundra Swan Conundrum (1 Viewer)

Hi All,

Occasionally, I run across a particular swan that leaves me scratching my head a bit. Though I can recognize a classic Bewick's Swan and a classic Whistling Swan, I am still troubled by some of the 'tweeners that are out there. Since they are but subspecies, I shouldn't really be surprised to find birds that appear intermediate, but nonetheless, there is the drive to want to ascribe them to one form or the other. Today I photographed a swan in southern Oregon that had extensive yellow loral skin. It was not as extensive as on the more yellow-billed forms of Bewick's, and there was no yellow over the top of the bill base, but in surfing through images of Bewick's Swans, there are examples with similar minimal amounts of yellow from the western Palearctic. Here is one example:
http://tinyurl.com/26ljg8

I have also included another shot I took this summer of three Tundra Swans seen on St. Paul Island, Alaska. They were widely regarded as being two Bewick's and one Whistling. The photo has been altered slightly to fit them into a tigher crop, since they were slightly more spread out in the original shot. There is one clear-cut Bewick's and one clear cut Whistling. The third bird has reduced yellow in the lores, much like the swan I saw today. I have looked through thousands of Tundra Swans in North America, and while I have seen a lot of variation, this represents the most yellow that I've seen on a bird that was not clearly a Bewick's. There was a clear Bewick's in the same general area last year (Klamath Basin), but that bird had very extensive yellow that connected over the top of the bill at the base. So the notion of a Bewick's Swan occurring along the Oregon-California border is not too far-fetched.

Anyway, I'm looking for input from birders from both sides of the pond. Do these 'tweeners look like Bewick Swans, and do North American birders see Whistling Swans showing this extensive of yellow in the lores? Before it gets raised by someone else, the yellow lores appear marginally more extensive than that illustrated by Sibley for extreme yellow-billed Whistlings in his field guide.

Chris

The bird showing the least yellow to me seems to have a slighty heftier bill than it's companions. Bewick's columbianus for me.

I think the yellow on the Klamath bird and the two Alaskan birds would lead them to be called Bewick's in Europe. Suggesting Whistling Swan would get you laughed at, if not worse!

Bewick's for me too. If i remember rightly, one or two of the Bewick's that Sir Peter Scott studied at Slimbridge had only a little and occasionally almost no yellow in the bill.

Mike

bewicks,did anyone else see the tribute to peter scott last week on tv,it described perfectly bewicks that wintered in the uk and every single one was different to the other and identifiable!!!

Hi All,

Thanks for the replies so far. Just giving this a little bump since I am interested in hearing from more folks. I'm not sure how many swans I've looked at in the past few days, but I've probably closely examined 5,000, and seen another 15-20,000. Anyway, I managed to find another Bewick's Swan yesterday that looks pretty clearly like a Bewick's. The picture is a composite showing both sides of the bill. I've also attached an image of a Whistling Swan (right hand bird in picture) showing the maximum amount of yellow seen on one that did not raise the possibility of Bewick's in my mind. I saw perhaps half a dozen swans with this degree of yellow. I am also eager to hear from North American birders who might get to see lots of Whistling Swans, and what sort of variability they have observed in yellow loral patches. Comments would be greatly appreciated.

Chris

Hi Chris

I agree with Xenospiza in that if these birds were in Europe, they wouldn't really get a second look as being Bewick's. Of course, thats not the same as positively identifying them on their own merits, but they certainly show a lot of yellow.

Probably the best that can be done with taxa like these is to call them "showing the characters of...", as unless you know their exact provence, its always a bit risky to identify them with absolute certainty.

The picture of 5 Tundra's together is interesting from a European perspective as it shows what an atypical Tundra looks like.

Cheers,

Chris,
I was intrigued by your photographs and I have to pretty much endorse what others have posted in reply and that is that these would be classed as Bewick's Swans in Europe. Could you tell me the location in southern Oregon if it is not confidential. I have done a rough estimate of the distance from west Alaska (Bering Sea) to 'southern Oregon' and it appears to be of the order of 2500 miles (4000 Kms). This is the distance that the Bewick's cover (one way) from the nearest breeding grounds in the north of Russia to the south west of England. You may also be interested in part of my amateur website at www.colinbutters.com to look at a variety of Bewick's Swan bill patterns. Although as you know, each bird has an individual pattern to the black and yellow but Peter Scott noted that these patterns fall into one of three very general categories. If you are unfamiliar with them I can describe them but the birds in you photographs fall into these patterns. To my eye, they are Bewick's Swans.