I've posted before about my otter as well as a beaver problem. I can tell you the otters will get the fish. I couldn't believe the amount of fish scales found on the far side bank of my pond. I bought some Victor Conibear traps and with the help of a friend who lives near my property we've been able to control them. The other thing is once they find your pond otters will come back. I'm sure they found my pond by the creek that runs through the property.