Context:

• Every year, thousands of sea turtles are accidentally captured, injured or killed by mechanised boats, trawl nets and gill nets operated and used by comercial fishermen.
• They can also sustain internal injuries from fishing hooks or suffer serious external injuries after becoming entangled in nets.

Types of Turtle Species:

• There are five species in Indian waters — Leatherback, Loggerhead, Hawksbill, Green and Olive Ridley.
• In India, though sea turtles are protected under the Indian Wildlife Protection Act of 1972, under the Schedule I Part II, they face grave threats. 

Bycatch:

• Bycatch is one such example, which is the name given to ocean animals that are unintentionally caught by fishing gear.
• Scientists are now working on programmes such as new fishing nets and gear that reduce the amount of bycatch while fishing.
• Growing public interest in bycatch reduction programmes is motivated by factors such as an appreciation for endangered species and concern for maintaining marine biodiversity.

Turtle Breeding Season:

• The turtle breeding season is usually between November and December.
• In Tamil Nadu, for example, the Olive Ridley nests between December and April along the Chennai-Kancheepuram coastline.
• The eastern coastline is the feeding area for Olive Ridley, juvenile Hawksbills and Green turtles.
• Off-shore waters are also migratory routes for the Olive Ridley while moving towards beaches in Andhra Pradesh and Odisha.

Role in marine ecosystem

• Sea turtles, especially the leatherback, keep jellyfish under control, thereby helping to maintain healthy fish stocks in the oceans.
• The Green turtle feeds on sea grass beds and by cropping the grass provide a nursery for numerous species of fish, shellfish and crustaceans.
• The Hawksbill feeds on sponges in the reef ecosystem and opens up crevices for other marine life to live in.
• Turtles are also transporters of nutrients and energy to coastal areas. Unhatched eggs, eggshells and fluids help foster decomposers and create much needed fertilizer in sandy beaches.
• As turtle populations in general decline, so does their ability to play a vital role in maintaining the health of the world’s oceans. Integrated conservation measures are needed to rebuild their populations to healthy levels so that they can carry out the full extent of their key roles in ocean ecosystems.

Workable solutions

• Under current regulations, mechanised trawl boats are not allowed to operate within 8 km of the shore in Andhra Pradesh, 5.5 km in Tamil Nadu and 5 km in Odisha. However, these limits are not being enforced.
• Similarly, nets set for ray fish are banned under the law during the season. However, their use by some categories of fishermen is widespread.
• The ban needs to be enforced at all levels of fishing and monitored by the respective Fisheries departments, marine police and the Indian Coast Guard. All areas where fishing boats land need to be monitored.
• In the U.S., all trawl shrimp fishing vessels need to be equipped with turtle excluder devices or TEDs, which are two-dimensional net inserts with large escape openings for turtles.
• Likewise in India, trawlers meant for shrimp fishing are required by law to be fitted with TEDs. If used correctly, TEDs have been found to reduce turtle captures by 90%.
• Areas where sea turtles forage and congregate need to be identified and additional seasonal closures need to be implemented within these areas.
• If sea turtle conservation is to have meaning, all trawl boats should be fitted with a vessel monitoring system that must be kept on at all times. This will provide a simple system of monitoring by the Coast Guard.
• These small but meaningful measures will help the sea turtles that are our marine heritage have another chance at survival.

Source:TH