December 4, 2008

Man-Made Noise Becoming a Huge Danger to Marine Wildlife

Man-made noise emitted in the seas and oceans is a huge risk to whales, dolphins and turtles that use sound to converse, find food and mate, wildlife experts announced on Wednesday.

Reverberating ship engines, seismic surveys by oil and gas companies, and invasive military sonar is generating an "acoustic fog and cacophony of sounds" underwater, frightening marine animals and disturbing their natural behavior.

"There is now evidence linking loud underwater noises with some major strandings of marine mammals, especially deep diving beaked whales," Mark Simmonds, Science Director of the Whale and Dolphin Conservation Society, announced at a news conference in Rome.

Simmonds, who spoke at the December 1-5 United Nations Environment Program's Convention on Migratory Species conference, added that there is mounting evidence that specific tissue damage in cetaceans is connected to the noise.

Experts suppose that anxious animals tend to dive irregularly and experience something comparable to human divers getting the "bends;" an illness with symptoms experienced when divers not properly decompress after a extensive or deep dive.

In the article "Ocean Noise: Turn It Down," a new description by the International Fund for Animal Welfare, the distance over which blue whales can commune has been reduced by 90 percent because of the greater noise levels.

In the past 50 years, frequency underwater noise has increased greatly 10 years over the previous decade, and at the same time the number of ships has tripled, the report also stated.

It also said that sound created by air guns used for seismic surveys in oil searching travel more than 1,864 miles from their source.

The growing number of ships, and their growing speed, has caused more ships to hit marine animals previously endangered by hunting and climate changes.

Experts insist that there are additional anxieties that mounting levels of carbon dioxide are raising water acidity levels and contributing to louder oceans, because when acidity increases, water absorbs a smaller amount of noise.

"If there is a lot of background noise, the animals can't hear the boat coming," said Simmonds. "It's the cocktail party effect."

The European Union has created a plan calling on convention members to ponder a decisive variety of options to decrease underwater noise.

However, Simmonds added that conservationists were also worried that demands from the military and energy industries, in addition to the need for additional research into marine noise pollution, could cause the resolution to become significantly diluted.

"We simply don't know at this stage how many animals are affected by noise pollution, but the lack of full scientific evidence should not be a reason to delay action," noted Simmonds.


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