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Drift Net
Drift netDrift nets are free-floating nets used in oceans to snare fish by their gills. Each net can measure up to 50 feet (15 meters) deep and 55 miles (89 kilometers) long. Because drift nets are not selective, many fish and marine mammals are trapped in them. Those unwanted by fishermen, such as sharks, turtles, seabirds, and dolphins, are removed from the nets and thrown back, dead, into the ocean. Drift nets are an extraordinarily destructive fishing technology. Ecological damage caused by drift netsDrift nets are used in all of the world's major fishing regions, and the snaring of unintended marine species is always a serious problem. This is especially true in the commercial fishing of swordfish, tuna, squid, and salmon. During the late 1980s, drift nets were estimated to have killed as many as one million dolphins and porpoises annually. In addition, millions of seabirds, tens of thousands of seals, thousands of sea turtles, and untold numbers of sharks and other large species of fish were accidentally snared and killed. Great lengths of drift nets and other fishing nets are lost at sea every year, especially during severe storms. Because the nets are made of materials that do not degrade or break down easily, they continue to snare fish and marine mammals underwater for many years. It is unknown how many are killed as a result of these so-called "ghost nets." In response to mounting concerns about the harmful nature of drift nets, the United Nations banned the use of those nets longer than 1.5 miles (2.5 kilometers) in 1993. Although this regulation would not eliminate the snaring of unintended species, it would reduce the amount killed by as much as two-thirds. Unfortunately, there has been a great deal of resistance from the fishing industry and fishing nations to this regulation. Many fisheries continue to use much longer nets. |
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Cite this article
"Drift Net." UXL Encyclopedia of Science. 2002. Encyclopedia.com. 30 May. 2012 <http://www.encyclopedia.com>. "Drift Net." UXL Encyclopedia of Science. 2002. Encyclopedia.com. (May 30, 2012). http://www.encyclopedia.com/doc/1G2-3438100233.html "Drift Net." UXL Encyclopedia of Science. 2002. Retrieved May 30, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1G2-3438100233.html |
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drift net
drift net or, more correctly, a drift of nets, a long shallow net or series of nets buoyed on the top edge with cork or with glass or plastic balls and weighted along the bottom edge with pieces of lead. Operated by a drifter, it hangs vertically downwards in the sea from the surface to a depth of 12–15 metres (40–50 ft). It is employed mainly in relatively shallow waters and is the means of taking fish which do not normally lie on the bottom, of which the more usual types are herring, mackerel, and pilchard.
See also fisheries. |
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Cite this article
"drift net." The Oxford Companion to Ships and the Sea. 2006. Encyclopedia.com. 30 May. 2012 <http://www.encyclopedia.com>. "drift net." The Oxford Companion to Ships and the Sea. 2006. Encyclopedia.com. (May 30, 2012). http://www.encyclopedia.com/doc/1O225-driftnet.html "drift net." The Oxford Companion to Ships and the Sea. 2006. Retrieved May 30, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O225-driftnet.html |
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drift net
drift net (also drift·net) • n. a large net for herring and similar fish, kept upright by weights at the bottom and floats at the top and allowed to drift with the tide. DERIVATIVES: drift net·ter n. drift net·ting n. |
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Cite this article
"drift net." The Oxford Pocket Dictionary of Current English. 2009. Encyclopedia.com. 30 May. 2012 <http://www.encyclopedia.com>. "drift net." The Oxford Pocket Dictionary of Current English. 2009. Encyclopedia.com. (May 30, 2012). http://www.encyclopedia.com/doc/1O999-driftnet.html "drift net." The Oxford Pocket Dictionary of Current English. 2009. Retrieved May 30, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O999-driftnet.html |
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