While Bill's comment on HSB not spawning in the pond is 99.9% correct, don't assume that they are sterile because they are not. The HSB just do not have the correct spawning habitat for the eggs to remain viable until they hatch.

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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).