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U.S. Navy to Reduce Sonar Use

Big win for groups seeking protection for marine mammals

A recent federal court settlement proves a major win for environmental groups seeking increased protection for marine mammals from the effects of sonar generated by U.S. Navy ships. A ruling earlier this year exposed the fact that the Navy and the National Marine Fisheries Services (NMFS) have repeatedly violated the Marine Mammal Protection Act by using sonar in areas along the California coast and around Hawaii. Under the new settlement, the Navy has agreed to greatly reduce the use of sonar in future training exercises in these areas.

The effects of sonar on marine life have been discussed for years, and its use has been linked to a number of injuries, and even death, among marine mammals. While the specific physical effects are not very well understood, marine mammals, particularly whales and dolphins, have been known to suddenly, rapidly change depth, bleed from their eyes and ears, swim great distances, or even beach themselves after being subjected to sonar. Whales hit by sonar blasts have even been found dead with bubbles in their veins and tissue, similar to the decompression illness that can befall divers. Extremely powerful Navy sonar tops out at 235 decibels close to the source, and can be as loud as 140 decibels 300 miles from the source. While the direct cause of these injuries are unknown, neither scientists nor the Navy deny the connection, as in the case of a beaching incident in the Bahamas. For comparison’s sake, 235 decibels are nearly twice as loud as standing directly in front of the speakers at a rock concert or standing 1,000 feet from a jet aircraft that’s taking off.

Under the new settlement, the Navy has agreed to cease and desist from using sonar and explosives in the sensitive waters of California and Hawaii, including known habitats and breeding grounds for numerous species of whales, dolphins, seals and sea lions. One such area off the coast of San Diego, for example, is a prime feeding ground for blue whales, and the use of sonar here is of course problematic. Any such training is to be conducted in areas where there is less likelihood of harming marine mammals.

The court case was brought to the federal authorities by environmental organizations, which state that they understand the Navy’s need to use sonar in training in limited areas. “By agreeing to this settlement, the Navy acknowledges that it doesn’t need to train in every square inch of the ocean and that it can take reasonable steps to reduce the deadly toll of its activities,” says David Henkin, an attorney for the national legal organization Earthjustice, which brought the initial challenge on behalf of Conservation Council for Hawai‘i, the Animal Welfare Institute, the Center for Biological Diversity and the Ocean Mammal Institute.

Despite this victory, as long as the Navy uses sonar in waters where marine mammals migrate or live, there will likely still be cases of harm caused by sonar. From a protection point of view, an all-out ban on sonar would have been optimal, but the organizations behind this settlement point out that they cooperated with the Navy to reach this settlement, and hope that this cooperation will lead to more agreements in the future.