ha ha ha
Or "heads", as real sailors call them.
A dredge is a vessel designed to remove sediment from the bottom, generally for the purpose of widening and deepening ship channels. However, the term is often applied to a specialized type of trawler. A clam dredge is a special type of trawler that takes clams from the sand. The device that actually does this is also called a dredge. Resembling a large steel cage, it is dragged across the sandy bottom, and rakes out the shellfish, along with rocks, debris, some bottom fish and lobsters, the occasional lost anchor, and anything else that is in its path.
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