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Published bySydney Lyons Modified over 9 years ago
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OVERFISHING PRACTICES GILL NETS DRIFT NETS LONGLINES PURSE SEINE NETS TRAWLERS
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BY-CATCH – ALL THE ANIMALS CAUGHT IN NETS OR ON LINES WHICH ARE UNINTENTIONAL AND ARE USUALLY DEAD AND THROWN OVERBOARD.
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Drift net fishing on the high seas beyond the exclusive economic zone of any nation was banned in 1991 by the UN General Assembly because of its potential to harm all fish stocks and marine animals. Fines for drift net fishing are significant. This type of fishing involves the use of a net, up to twenty miles in extent, that is generally anchored to a boat and left to float with the tide. The net is set out at night and pulled in at sunrise, making it difficult for aircraft surveillance to catch them in the act. On average, a drift net vessel can scoop up half a ton of fish per day. This often results in an over harvesting and waste of large populations of non-commercial marine species (by-catch) by its effect of “sweeping the ocean clean”. The by-catch also includes marine mammals and seabirds.
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Nicknamed "walls of death" these nets are made of a very strong monofilament (single strand) nylon mesh, and each net is between 8 - 12 meters deep and may be as long as 65 km, although usually between 32 - 40 km. The nets are often put into the sea at night, where they drift with the current, catching and killing anything that gets in their way, like huge underwater spiders' webs. This method of fishing is extremely wasteful. Not only is an estimated 40% to 50% of each catch lost when the net is hauled in, but uncounted numbers of fish are injured in the net and may escape only to die later. These nets also catch many dolphins, whales, seals, turtles and seabirds which cannot easily see the almost invisible netting.
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Longline fishing is a technique used to catch fish in open waters, including those who live near the sea floor. A longline includes a main fishing line up to 100 kilometers in length, with secondary lines branching off it, each set with hundreds or thousands of barbed, baited hooks. This technique is used in international waters, as well as waters controlled by the United States, South America, Australia, New Zealand, and southern African countries, and targets fish species such as tuna, swordfish, and Patagonian toothfish.
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The Turtle Excluder Device or TED is a grid of bars with an opening either at the top or the bottom. The grid is fitted into the neck of a shrimp trawl. Small animals like shrimp slip through the bars and are caught in the bag end of the trawl. Large animals such as turtles and sharks, when caught at the mouth of the trawl, strike the grid bars and are ejected through the opening.
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Japan has secured the help of eleven nations at the IWC in this way: six East Caribbean states, (Antigua and Barbuda, Dominica, Grenada, St Lucia, St Vincent and the Grenadines, St Kitts and Nevis), the Solomon Islands, Guinea, Morocco and Panama. All of these countries regularly attend IWC meetings and speak in favor of a resumption of commercial whaling, voting with Japan on all occasions
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