That's what I would think. They may be remembering conditioning from last year if last year they felt footsteps and followed you around the pond waiting for something to jump in. Grasshoppers, frogs, etc.

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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).