Sea turtle populations have dramatically declined in numbers over the past half century. Green sea turtles (Chelonia mydas), hawksbills (Eretmochelys imbricata), Kemp's Ridleys (Lepidochelys kempii), loggerheads (Caretta caretta), and leatherbacks (Dermochelys coriacea) have all had their numbers decimated by human activity. The decline has been caused by several factors, including the development of a highly industrialized fishery to meet the demand for seafood on a worldwide basis. The most economical fishing method involves pulling multiple nets underwater for extended periods of time, and any air-breathing animals, such as sea turtles, which get caught in the net are usually drowned before they are hoisted on board.

Loggerhead sea turtle returns to sea after laying eggs on a Florida beach. (Corbis-Bettmann. Reproduced by permission.)

In the United States, this problem has led to the introduction of the turtle excluder device (TED), which must be placed on each tow...