Otters are really hard on the fishery. They catch a lot of the biggest slowest fish. I'd contact the DWR and see if you can get a depredation permit that allows you to trap them all year round, and see if the beaver can be included.

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3/4 to 1 1/4 ac pond LMB, SMB, PS, BG, RES, CC, YP, Bardello BG, (RBT & Blue Tilapia - seasonal).