Pumpkinseeds won't spawn multiple times a year (that I know of). I think that you don't have enough forage in there for the amount of LMB that are there.

What size are the PS that you normally catch? Same for the YP.

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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).