Purse Seine Fishing
Why in News?
The Supreme Court directed Tamil Nadu to expedite processing of “Access Pass” applications for purse seine vessels to fish in the central Exclusive Economic Zone (EEZ), holding that administrative delays amounted to an impermissible “unwritten ban”.
About
- The Mechanism: It is an open-water fishing method where a huge vertical wall of netting is laid out in a circle to completely encircle a dense school of fish.
- The "Pursing" Process: Once the fish are surrounded, the bottom of the net is drawn tight by hauling a purse line (much like tightening the drawstrings of a laundry bag or purse), trapping the fish inside.
- Scale of Operation: These nets can be massive, often measuring more than 2,000 meters in length and reaching up to 200 meters in depth.
- Target Species: It primarily targets pelagic (midwater) fish that swim in dense schools close to the surface, such as tuna, mackerel, sardines, and anchovies.
Advantages of the Method
- High Efficiency: It is an incredibly effective method for harvesting massive volumes of schooling fish in a single operation.
- No Seabed Contact: Unlike destructive bottom trawling, open-water purse seining does not scrape or damage the seafloor or benthic habitats.
- Low Benthic Bycatch: When executed correctly in the open ocean on single-species schools, it can yield relatively low levels of unintended bottom-dwelling marine bycatch.
Environmental Concerns
- Threat to Traditional Livelihoods: Because mechanised purse seiners scoop up entire shoals of fish rapidly, they leave dwindling stocks for traditional, small-scale fishermen who operate close to the coast.
- Decline of Small Pelagic Fish: The practice is blamed for the severe drop in populations of local favourites, such as oil sardines and mackerel, along India's western and southern coasts.
- Bycatch Risks: When operators use Fish Aggregating Devices (FADs)—floating objects used to attract fish—the nets indiscriminately trap juvenile fish and endangered non-target species like sea turtles, dolphins, and sharks.
