Depends on the lake you're fishing. The shells may act like rocks in other lakes, too heavy to fan out. Beds on our HOA lake have shells in them too because there are just so dang many shells from the snales in the lake. Might not be old beds, but might be. If you were close enough to see the shells you were close enough to scare away the fish. Clear water bedding fish as spooked easily. I find the beds on one pass, go find others, then start fishing them in a circuit fashion.
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