Al, I am flabbergasted by your news! Please know that C24 has the yellow on both sides, the yellow marking being a diagnostic one for tundra swans...hmm...anyhow, many thanks for your kind words. I'm no swan expert, that's for sure, but I'm not convinced...why the yellow markings on both sides? Only the swan can answer this. I only mention this because from what I've read, trumpeter swans DO NOT have this marking. It seems like quite a coincidence that this swan should have yellow markings at the base of his bill, on both sides, and NOT be a tundra swan. Ah, the mysteries of birds! Thanks again for the comments, and please know that I am very puzzled by all this!
All the best,
David