Welcome to the forum!
Muskrats and beaver are primary burrowing concerns pond owners harbor. Mink prey upon muskrats, voles, frogs, and there are reports of them hammering cormorants too, which in my book makes them a preferred visitor on my ponds. I don't mind sacrificing a few fish knowing my pond is being patrolled by mink. They are solitary and rarely seen - at least in my experience.
I have personally watched a mink aggressively hunt a Canadian goose in the water. I was shocked but not surprised they would try. They are tuff little buggers.
Look up 160 coni-boxes. I have had very good luck with these once the water if frozen. They do like fresh bloody meat. Place it between the wire mesh end and the coni. Make sure the trap is well wired down in case you get a martin. A martin will take your whole set.
Cheers Don.