My 2.5 acre pond built summer 1990. Stocked it with 20lbs fatheads, 350 catfish 4" to 6" long, 350 catfish 6" to 8" long, 600 coppernose blue gill fall of 1990. March of 1990 I added 500 Florida bass. Added 12 grass carp in 2002. I left everything alone, didn't take anything out for about 2 years. For awhile the catfish fed very well. Bass have always been hard to catch but I know there some big ones there. The catfish disappeared. This spring I had a long trot line out for three days and nights and caught one small catfish. I don't see nor do we catch the bluegill anymore. The catfish disappeared before my otter infestation and I assume the otters got the blugill. Not sure what they did to the bass. I'm thinking of restocking the catfish and bluegill. Not sure just what is there any more. Really don't want to do the shocking procedure. Would I be doing okay to add catfish and blue gill and see what happens? In addition to having bass fishing I would like to have the catfish and blue gill too. The max depth is 17 ft. Pond is located in the pine hill of East Texas.
I'm not sure how small a fish an otter will fool with but he WILL clean out a pond.
You'll have to start over with everything except maybe the fatheads.
I'm sure you know however the first order of business though is not to repeat history.
However it has to be done, legal or illegal the otter has to go or the pond has to go. There can be no inbetween. Check for legal first. In my state the local wildlife officer can connect you with a trapper if you are not adept at trapping.
Have not seen any otter signs in quite awhile. I put a post on some time back about the beavers and otters. As near as I can tell the otters are gone. Probably ate all they could and left. I know they can and do come back but we are watching for any signs. I guess I will restock and see what happens. I thought I was stocking by the book originally. In a pond as I described,what would be the recommended quanties of bass, bluegill and catfish to add to what may be some existing population? I don't think there any legal issues with the otters.
This link may help:
http://www.sdafs.org/tcafs/manuals/pond/ponds.htm I think you were ok on all numbers of fish except I believe you should have stocked more bg. If memory serves (which is irratic these days) you need 1000 bg per ac.
Again I emphasize being prepared for the otters. They already know where your pond is & I assure you they will be back. A 330 conibear works good in a slide (placed completely under water) or a snare above water. Domestic animals will not fight a snare & can be released if acidently caught.