I have a small pond with waterfall, about 4'x7'. It goes from 12" to 24" deep and that's enough for the winters here, my gold fish stayed alive even with 2" ice on top a couple of years ago. Well last fall I had a visit from a great blue heron, my wife saw it on the fence and didn't think why it was there, so it ate about 12 5'6" fish. When I replaced them I covered the pond with that black plastic deer netting, fairly invisible and no trouble until now. I found my netting all messed up, plants uprooted, large rocks fallen into the water, and even some good sized rocks on TOP of the net. Other than a human, I figured the only things we have in the area that could have done this were racoons.
This time they ate close to 20 fish, so it may have been a whole family. Now I have green "rabbit" wire fencing (1/2" squares) over it, and will wait until spring to get new fish, but now it's ugly and defeats the purpose of a pond to have a fence over it. If I place it under the water the fish can't come up to get their food. Any ideas?