In 2012, the National Marine Fisheries Service (NMFS) granted permission for the Navy to use low-frequency active sonar as part of its peacetime training and testing activities. The approval was valid for a period of five years, and applied to exercises in the Indian, Pacific and Atlantic Oceans as well as the Mediterranean Sea. In the same year, environmental groups led by the Natural Resources Defense Council (NRDC) filed a counter-suit, claiming that the approval put vulnerable cetacean and pinniped species at risk and did not fulfil the terms of the Marine Mammal Protection Act.
On July 15th, California's Ninth U.S. Circuit Court of Appeals ruled in favor of the environmentalists. The Marine Mammal Protection Act states that peacetime oceanic programs must have "the least practicable adverse impact on marine mammals," a stipulation that the court unanimously agreed the approval had failed to uphold. The court did not place the blame on the U.S. Navy, however, which it stated "has been deliberate and thoughtful in its plans to follow NMFS guidelines and limit unnecessary harassment and harm to marine mammals." Instead, the court pointed the finger at NMFS.
The terms of the original approval required the Navy to shut down or delay sonar use when a marine mammal was detected near the ships, and also banned sonar pulses near coastlines and in protected waters. However, the court ruled that the areas classified as "protected" by the NMFS were inadequate, in reality doing very little to shield vulnerable marine mammals from sonar-generated sound waves capable of reaching 235 decibels. To put that into perspective, the sound of a 12-gauge shotgun being fired is 165 decibels, while the average rock concert reaches just 115 decibels.
Underwater, sonar sound waves can travel for hundreds of miles. They are found in approximately 70 percent of the world's oceans, and can measure up to 140 decibels at a distance of 300 miles from their original source. Scientists believe that this noise pollution causes severe stress for marine mammals by interfering with their echolocation and communication systems, and forcing them to alter their feeding and mating behavior. According to NRDC's Marine Mammal Protection Project Director Michael Jasny, "marine mammal species perceive these [sonar] sounds as a threat and react accordingly."
Navy sonar exercises have been linked to several mass strandings, including the 2002 stranding of 14 whales in the Canary Islands. Autopsies showed that the whales had gas bubbles in their tissues, leading some to hypothesize that sonar may cause decompression sickness in cetaceans. At this point, it is not clear what the court's ruling means for the future of U.S. Navy low-frequency active sonar. The case has been returned to the district court for further consideration, but it is hoped that scientists will eventually find a way for marine-mammal conservation and national defense to co-exist.
The post Court Rules in Favor of Marine Mammals in U.S. Navy Sonar Debate appeared first on Scuba Diver Life.
from Scuba Diver Life http://ift.tt/2atOcSd
No comments:
Post a Comment