Hopefully, he has street smarts and stays in the water at night. If he stays on the bank, that is the problem because the foxes and other predators can walk out and grab him. If you can ever capture him, the best solution would be to bring him indoors and keep him there until the whole pond thaws. By moving him indoors for several nights (week or more), the foxes may come back off and on sporadically, but if they can't see him, they will usually move to another area for search of food. Again, there are no guarantees with predators.

Can you access the opening of water with a boat or kayak now, that you could herd him towards your house? If you can capture him, you might want to begin training him to come in at night as the weather clears. Let us know how this works out. The Regal Swan