Noise Pollution Disrupting Sea Life

The world's ocean habitats, already stressed by over-fishing, pollution, and global warming, are far from silent. While the sound level caused by waves in empty seas is 80 decibels, human activity - supertanker engines, or guns fired at the seabed during oil exploration - often exceeds 180 decibels. This is 10 billion times louder on the geometric decibel scale. Whales shy away from sounds over 120 decibels. Underwater sounds can travel vast distances; an explosion off Australia was once detected in Bermuda