Fish caught in and around coral reefs are served in some of the fanciest restaurants or sold at boutique pet stores. Overfishing depletes various segments of the marine food chain and is the biggest threat to the world's coral reefs. Methods used in commercial fishing can also have terrible consequences on coral reefs. Cyanide fishing is a common commercial fishing method used by more than 15 countries. Cyanide is dumped into the sea to stun reef fish for easier harvesting. The cyanide used in this process poisons the reef, and kills about 90 percent of the fish living in it [source: Ocean World]. Blast fishing, where explosives are used to stun fish, also inflicts terrible consequences on reef life. Blast fishing is allowed by more than 40 countries [source: NOAA]. Another destructive practice is pounding the reefs with nets to scare fish so they will emerge from crevices in the reefs. This practice is called muro-ami netting [source: World Resources Institute].
Artisanal fisheries, which are local, smaller scale fisheries that use more traditional methods, have long been thought to have no effects on coral reefs. In the past decade or so, however, some concern has been raised regarding their potential impact on coral reefs [source: Hawkins]. These fisheries are very important to economies in developing countries, but can extract millions of tons of fish, and it takes only a small percentage of missing fish to alter the biodiversity and sustainability of a coral reef.
Since 1998, the threat to coral reefs from overfishing and destructive fishing practices has increased 80 percent [source: Burke]. Coral reefs around the world are dying. Although this may seem unimportant to those who don't dive near them or visit the areas where they're located, coral reefs are important to ocean systems. The reefs are home to more than 4,000 species of fish and 800 types of coral [source Burke]. In addition to their importance to fish and other marine life, the reefs contribute to storage of carbon and calcium and affect water flow, upwelling and geological formations [source: Planetary Coral Reef Foundation].
Blast fishing, which destroys coral by ripping it apart, is used in more than 40 countries. (Steve Winter/National Geographic/Getty Images)
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