How much fishing pressure has the pond seen in the past 3-5 years? It could be that the LMB are there, but just too educated to take an artificial bait. Have you tried fishing with a large shiner or a 3"-4" BG as bait?

Hybrid Bass. You talking about Hybrid Striped Bass, Florida/Northern Black Bass cross or a Largemouth/Smallmouth cross?

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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).