Only five fish left. One more was taken last night. I guess it is a river otter. There is a small stream about 1/2 block from the pond. That must be where the otter lives. I can see where the animal has made a path in and out of the pond. Last night I set a spring trap in that path but didn't catch him, but he got a fish. Had seven nice koi and about fifteen gold fish. Now down to five goldies. Interesting the otter took the large koi first. The otter will no doubt get the last five fish. It looks hopeless to replace the fish next spring.