Tundra Swan (Cygnus columbianus)
Tundra Swans should have a yellow spot on the bill, in front of the eye. I believe this is Trumpeter Swans.
Hi, Gary. Good observation. I really don't know. This photo was taken in Cambridge, MD last year. However, if it is a Trumpeter Swan it would be extremely rare in our area and I think I would have known about its presence. But one never knows for certain.
Sibleyguides.com provides an excellent comparison of the two (Tundra and Trumpeter) and it states that in 10% of the cases the bill is all black and 10% have a larger yellow spot than normal. Raising the issue is quite helpful because it illustrates this variance.
Thanks for bringing it to my attention. I really never gave it a second thought. I just assumed it was a Tundra Swan. A "real" birder would have done more analysis, which I didn't do.
Thanks for the link. I was questioning the difference in the size of the yellow spots. The picture I posted had the largest yellow spot of any of my pictures, only have a few closeups. None of the other pictures were good enough to post. The Tundra Swans usually over fly this area without stopping. Last fall I photographed some Tundra Swans by accident, they were mixed in with Trumpeters. I didn't see the yellow spots unit looking at the pictures at home on the computer.
I'm strongly suspecting this one is a Trumpeter Swan, too - not just the lack of yellow, but also the bill length, and the rounded back (per Sibley). Anyone else any thoughts?
Edit: updated link to Sibley page above: http://web.archive.org/web/20071219061623/http://www.sibleyguides.com/swans.htm
This message was edited Feb 7, 2011 5:24 PM
Sorry for the delay in responding but I am not in a position to call it one way or the other. So, I decided to go to my local resident expert for his opinion. This is what he said:
"Thanks for sharing the swan image. I'll be the first to say that swans present a much more difficult ID challenge than many give credit. At last year's MD/DC Records Committee trip to the Smithsonian, we spent a lot of time reviewing Tundra vs. Trumpeter, and especially as young birds, they are really tricky. Among the challenges are bills that are still filling in as they arrive in our area and highly variable feathering around their bills. Although this is probably an adult bird, the details of the "pinched" area in front of the eye, as well as the border of the bill, can appear variable depending on how the feathers have grown in. That said, I think there's enough here to call this bird a Tundra. As you pointed out, the lack of yellow does not support one species over the other. Yellow can confirm Tundra but not rule out Trumpeter. I think the following combination confirms Tundra:
- Lack of 'widow's crown', overall a very rounded head.
- Overall bill length and impression.
- Details in shape of the bill, including a slight concavity/slope on the upper mandible.
- Base of the bill is more vertical than rounded and angular. (Though slightly more angled than the most obvious Tundras.)
I'd say that the lack of a 'pinched area' in front of the eye (making the eye stand out less than average in the face) was the most confounding detail, but again, some minor changes in feathering on an individual can change this appearance.
I feel good calling this a Tundra. I also sent the image as a sanity check to two friends who independently agreed with that ID."
Interesting! I had never read such a detailed annalist. Learn someting new everyday.