Sea Turtle Conservancy

Information About Sea Turtles: Threats from Commercial Trawl Fishing

The Problem: It is estimated that thousands of sea turtles are injured or killed each year as a result of commercial fishing activity in U.S. and international waters. Many of these injuries and deaths take place while turtles are migrating through fishing areas. The turtles, attracted to the bait, get caught on the hooks used to catch fish.

As it stands, the global fishing fleet is currently 2.5 times larger than what oceans can sustainably support, which shows how big a threat commercial fishing practices pose to turtles. In 2004, the National Marine Fisheries Service (NMFS) identified more than 70 fisheries, operating in state and federal waters, as potentially harmful to sea turtles. Turtles are air-breathing reptiles. When they are caught underwater in nets or on lines, they drown if they are unable to reach the surface for air. They can also sustain internal injuries from hooks or external injuries from entanglement, including strangulation or amputation. The ropes used by fisheries can also entangle and drown them.

In the United States, sea turtles are protected under the Endangered Species Act. Beyond U.S. waters, there is no force of law to initiate and support bycatch reduction programs. Nevertheless, the growing international interest in reducing bycatch is motivated by numerous factors such as appreciation for endangered species and concern for maintaining marine biodiversity. The economic interest in preventing future environmentally-based fishing embargoes such as the U.S. tuna embargo (a ban on foreign-caught tuna caught by setting on and killing dolphins) also encourages governments and fishermen to reduce sea turtle capture in fisheries. Bycatch is a serious threat to sea turtles because it can occur anywhere in the ocean, making it hard to implement multi-national agreement that improve equipment requirements.

Species Affected: All sea turtles are affected by commercial fisheries. Loggerheads and leatherbacks have the greatest risk because of their feeding habitats.

The Solution: The use of Turtle Excluder Devices or TEDs, two-dimensional net inserts with large escape openings, in shrimp and other trawl net fisheries. Trawls are wide-mouthed nets that taper to a small end to hold the catch. Further, a shift by longline fleets, which positions miles of gear with one mainline and thousands of secondary lines and hooks, from “J” hooks to circle hooks to reduce the number and severity of sea turtle interactions with longline gear. Time and area closures have been instituted in the scallop dredge fleet and various gill net fisheries to protect sea turtles.
* Show support for companies and countries employing TEDs;
* Make sure that the fish you buy from your local grocery store are caught by these turtle-friendly fisheries;
* Inform and encourage family and friends to purchase seafood from responsible fisheries.

Case Study: In a study conducted by the NOAA Fisheries Pascagoula Laboratory and the NOAA Fisheries Miami Laboratory, in cooperation with Blue Water Fishermen’s Association, encounters with leatherback and loggerhead turtles were reduced by 65 and 90 percent, by switching from the traditional hook to the larger circle hooks. This research was such a success that NOAA Fisheries now requires the use of these new technologies in U.S. longline fisheries in both the Atlantic and Pacific. Specifically, U.S. longline fishermen in the Pacific are now required to use circle hooks instead of the standard industry J-hook and squid bait and are required to carry certain types of equipment and utilize handling protocols to facilitate the safe release of sea turtles.

Related links:
* Sea Turtles & U.S. Fishery Interactions
* International Fisheries