IIRC, what I read said that after a flood, enough were washed into the water that BG died after eating too many. No mention of the size of the BG. Like Dave said, I doubt that it would be an everyday concern.

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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).