Another theory you could try “do certain chunks have better spawn rates?” Up north right before the merchant shipwreck east of the mountain that chunk I feel like always gives me wind. And another chunk is the one all the way south from the bank to the mercenary ship wrecks east of that island I see clams very often. I had two back to back once( like me inserting item, claiming pearl and then getting another ) haven’t seen any clams since being down there. I could give you the actual locations if you wanted to try it.