Researchers have found evidence that military sonar is killing whales and dolphins around the world by driving them to the surface too quickly, resulting in a fatal case of what divers call the bends.
Scientists have known for several years that whale strandings and deaths are connected with the use of naval sonar, which uses loud sound to detect submarines, but they haven't been able to establish why.
A team of British and Spanish researchers studied 14 beaked whales that died in September last year after beaching in the Canary Islands near the site of a Spanish-led international naval exercise. The whales became stranded four hours after the mid-frequency sonar was used as part of an antisubmarine drill. The researchers found bubbles of gas in their internal organs similar to those found in scuba divers who surface too quickly and get decompression sickness.
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