Shrimp trawlers use wide-mouth, funnel-shaped nets that drag along the bottom for several hours at a time and catch everything within just a few feet of the bottom. Then they haul their catch up and dump it on the deck of the boat, pick the shrimp from the pile and then push everything else -- "trash", as they call it -- back into the water. Personally, I have seen all kinds of bottom fish and crabs, a shark, a spittoon and a rowing machine brought up in the "tail bag" of a trawling net. But to stop the drowning of turtles caught in trawling nets, "TEDs" (Turtle Exclusion Devices) are now a required escape opening just ahead of the narrow "tail bag" where the catch is held until hauled up and dumped on the deck for culling...

"In 1987, the United States [began requiring] all trawling shrimping boats to equip their nets with turtle excluder devices..."