I've never paid much attention, but I can't remember seeing anything eating them either. If they swarm again I'll catch a handful that haven't been sprayed and see if the pond fish are interested in 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).