For those of you who like to read, here's a nice report from the Department of Fish and Wildlife about Spotties.
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In California waters, adult spotted sand bass have a diet that consists primarily of crabs and clams, with fishes forming a relatively small component of their overall food compliment. The crab component consists of brachyuran crabs, and the dominant bivalve in the diet is the jackknife clam.
It's interesting that the bait we use is imitating the least important part of their diet. I think maybe experimenting with some crab creature baits might be worth a try.