If you have any docks or platforms near shore, they can be bolted down to the platform. But, if somebody wants to steal something there's almost no way to stop them. They could also be put out on floating platforms so you need a boat to reach them.

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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).