I'm not sure I know the answers to your questions. It looks like the beak is in the process of healing, but I did not realize before how extensive and numerous the lesions are. The swelling on the left side of the face at the beak attachment does not appear to be a discrete tumor, but resembles swelling of the surrounding tissues (soft tissue and/or possibly bone involvement??).

I must confess, I have not been keeping up with your website. I simply don't have the time. I rarely respond to e-mails. I was only answering the question ("What could this be?") based on a photograph and nothing else. How long ago did this problem begin? Was it a sudden, overnight problem or more gradual in onset? Is the swan eating? Is it the only one affected? Has it been examined by a veterinarian?

If the swan has not been examined by a veterinarian, then it needs to be. Things may not be what they seem by looking at a photograph.

Good luck with this particular problem. I do hope it is nothing too serious.
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