I'm very familiar with that swan at Parvin's. He hangs out in the west side of the lake where the river starts to form. That swan is very aggressive and has tried to attack me a few times. I respond to his aggressive moves towards me by making aggressive moves towards him, which quickly reminds him who's higher up on the food chain. Then he keeps his distance.
I have a friend who's 6'4 and that swan snuck up behind him while he was fishing from a kayak on Parvin's and grabbed a hold of his arm and capsized his kayak. I told him to string razor wire around his kayak the next time he fishes there.
I'm very surprised to hear that that swan attacked somebody in February though. Falling into 40 degree water is a serious, life threatening situation. I paddle lakes that have as many as ten swans on them, and in the fall and winter I can't get within a hundred yards of them before they fly away.