A TED is a grid of bars with an opening either at the top or bottom of a trawl net. The grid is fitted into the neck of a shrimp trawl. Small animals such as shrimp pass through the bars and are caught in the bag end of the trawl. When larger animals, such as sea turtles and sharks, are captured, they strike the grid bars and are ejected through the opening. Graphic courtesy of NOAA