The otter trawl as it is lowered from the research vessel "Walnford" of the NJ Marine Sciences Consortium, near Sandy Hook, NJ. The two large "barn doors" at the sides of the net act as hydrofoils underwater, keeping the net agape. They were originally called "outer boards," which term became corrupted to "otter boards"; hence the name of this rig. Larger versions are used for commercial fishing.