Fish, sea mammals ‘going deaf’ and dying in once-silent depths
By Steven Edwards
UNITED NATIONS - Environmentalists demand international action against man-made sounds in the oceans, saying fish and sea mammals are going deaf and dying because of noise pollution in the formerly silent depths. Ship traffic, military sonar and seismic air guns used in oil and gas exploration are creating a cacophony that is drowning out the natural sounds of marine life, the activists told a United Nations conference last June on oceans and the law of the sea.
They want ships fitted with quieter engines and other machinery, navies to invent more fish-sensitive sonars, and oil and gas companies to use their exploration guns only when they’re sure there are no schools of fish, whales or dolphins around. Some areas, they add, should be declared sea sanctuaries where all human activity is banned.
The demand for international regulations comes collectively from the North American Ocean Noise Coalition, the European Coalition for Silent Oceans and the South American Noise Coalition. Members of the groups announced their campaign at the UN on June 8, 2005.
“Deadly man-made sounds are invading the silent world, and are largely unregulated,”
said Marsha L. Green, an animal behaviour scientist who is also part of a U.S. federal advisory committee on acoustic impacts on marine mammals. “Some sounds are so loud and intense, they are injuring, deafening and killing marine life.” Citing her own research, she said whales will flee from a sound at 25 decibels, which is roughly the noise emitted by the engine of a small inflatable craft. But oil and gas air guns blast with a noise intensity of 240 dB. “Because we are talking about a logarithmic scale, that’s a trillion times louder,” she said.
Intense and sudden noise causes brain haemorrhaging and disorientation in marine life, the activist groups say. They argue reduced catch counts of 45 to 70 per cent in the aftermath of major noise activity show fish have either left the area or been killed.
The disorienting effect on whales, dolphins and squid, they add, comes from numerous examples of “stranding” on beaches immediately following known sonic activity. One of the most recent cases involved the beaching of 34 whales in North Carolina in January 2005, following U.S. navy sonar tests. Other beachings believed related to noise pollution have occurred over the past 30 years throughout the Caribbean and in Hawaii, the Canary Islands, Corsica and Greece. “Squid have been found with exploded ears, and exploded organs,” said Green.
- The Vancouver Sun