The US Navy may hurt more dolphins and whales by using sonar and explosives in the Pacific Ocean than thought, according to a more thorough analysis that reflects new research and covers naval activities in a wider area than previous studies. The Navy estimates its use of explosives and sonar may unintentionally cause more than 1,600 instances of hearing loss or other injury to marine mammals each year, according to a draft environmental impact statement that covers training and testing planned from 2014 to 2019. The Navy calculates the explosives could potentially kill more than 200 marine mammals a year. A notice about the study was due to appear Friday in the Federal Register. The Navy uses sonar to track enemy submarines, torpedoes, mines and other potential threats underwater. Scientists say the sound may disrupt marine animals' feeding patterns and startle some species of whales, causing them to surface rapidly. The old Navy analysis, covering 2009-2013, estimated unintentional injury or death to about 100 marine mammals in Hawaii and California, although no deaths have been reported. The larger numbers are partially the result of the Navy's use of new research on marine mammal behavior and updated computer models that predict how sonar affects animals.
