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Commercial marine fishing employs various methods to harvest fish and other marine organisms from oceans and seas. These methods vary in scale, technology, and environmental impact. The most common techniques include trawling, purse seining, longlining, and gillnetting.
Trawling involves dragging a large net through the water column or along the seabed. Bottom trawling targets demersal species like cod and flounder, while midwater trawling catches pelagic fish such as herring and mackerel. This method is efficient but can cause significant habitat destruction and bycatch.
Purse seining uses a large net to encircle schools of fish near the surface. Once the fish are surrounded, the bottom of the net is drawn closed like a purse. This method is highly effective for catching tuna, sardines, and anchovies but may also entangle non-target species.
Longlining involves setting a main line with numerous baited hooks attached at intervals. This method targets species like tuna, swordfish, and halibut. While selective, longlines can accidentally catch seabirds, sea turtles, and sharks.
Gillnetting uses vertical panels of netting that trap fish by their gills. These nets can be set at various depths and are used for species like salmon and cod. However, ghost fishing from lost or abandoned nets poses a threat to marine life.
Other methods include trapping with pots or traps for crustaceans like lobsters and crabs, and dredging for shellfish such as clams and oysters. Modern commercial fishing also relies on advanced technologies like sonar, GPS, and satellite imagery to locate fish stocks efficiently.
Sustainable practices are increasingly important to minimize overfishing and ecological damage. Regulations, quotas, and gear modifications help reduce bycatch and protect marine ecosystems. The future of commercial marine fishing depends on balancing economic interests with environmental stewardship. |
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发表于 2025-10-29 03:43:32