Dictionary of Ichthyology
beam trawl = a trawl with short wings and a head rope attached to a metal or wooden beam 4-12 m long. The beam keeps the net open horizontally while metal frames on each end of the beam keep the net open vertically. The beam has metal runners to support it off the sea floor and the tapering bag net drags over the bottom. These trawls may have tickler chains to disturb the fish so the net does not ride over them. Experimental electrified ticklers have been developed to be less damaging to the sea bed. Beam trawls are used mainly for flatfish (and shrimp).