its highly possible that it is the same bird. The Whooper cygnets are generally mostly all white by the time they fly back to Iceland, Just a few smudges of brown on the head, neck and back give it away and of course the lemony coloured bill. When cygnets come back the year after (Yearlings) I think you distinguish them by greyish/brown marks on the crown (Not 100% sure).
The Whooper cygnets at Martin Mere and Caerlaverock are defiantly starting to get yellow on their bills now.
Kane

looked like the same bird to me today-still with the mute swans-flew off west at 2.30pm.

Does any body know if the Juv Whooper that was frequenting Pennington Flash in late October/early November has been putting in an apearance every now and again. A Juv Whooper flew into Rammies today at 1215hrs(27/12/07) and showed well in front of Horrocks Hide. It seems more advanced than the one present in October. The October bird had a pink/cream bill patch, but the bird today had a cream patch with a hint of yellow where the bill joins the head. How long does it take a juv to become adult and is it possible this is the same bird or has it advanced to quickly for it not to be- answers on a post card please. The info in field guides and ont tinternet is poor.