Navy to resume use of controversial sonar

In a Jan. 23rd announcement, the Department of Defense (DoD) unilaterally exempted the Navy from federal laws intended to protect whales and other marine mammals. The exemption will allow the Navy to resume its its use of high intensity, mid-frequency sonar that is believed to have contributed to several whale beaching incidents and other whale fatalities around the world. The Navy, who was sued for using mid-frequency sonar under the Marine Mammal Protection Act (MMPA) by a coalition of environmental groups in 2005, will be allowed to operate under the DoD exemption until 2009. The Navy insists that continued training with the sonar system is "absolutely essential in protecting the lives of our sailors and defending the nation." However, the National Resource Defense Council (NRDC), one of the groups that launched the 2005 lawsuit, says the DoD authorization is tantamount to an admission of guilt in previously breaking the MMPA. "It's not that the Navy can't comply with the law, it's that the Navy chooses not to," says Joel Reynolds, an NRDC attorney familiar with the case. The DoD claims that the exemption is a "bridge" allowing the Navy to operate until a comprehensive strategy for complying with federal law will be completed in 2009. Greenpeace responded, stating that they believe the DoD and the Bush administration are avoiding their legal responsibilities to protect marine mammals by exempting the Navy from the MMPA and the Endangered Species Act on this issue. The DoD claims Congress authorized it to make the exemption as part of the 2004 National Defense Authorization Act (NDAA), but environmental groups claim that the DoD acted unilaterally on the issue. Congress addressed the issue in 2004 by redefining "harassment" of a marine mammal from any military action that constitutes an "annoyance" to the animal and has the "potential to disturb" it, to being defined as anything that has a "significant potential to injure" or is "likely to disturb" animals. The changes do not appear to authorize the DoD to grant an outright exemption to the Navy from the MMPA or the Endangered Species Act. In December of last year the California Coastal Commission (CCC) took a stand on the issue, releasing a report on the effects of human caused noise pollution in the oceans on marine mammals. According to the CCC report, marine mammal strandings and mortalities have been linked to exposure to mid-frequency sonar, the noise from which can kill, injure and deafen whales and other marine mammals. While many marine mammals such as seals and sea lions do not appear to be affected by the sonar, beaked whales appear to be particularly sensitive to the noise. The CCC report states that strandings of Cuvier's beaked whales are highly unusual. "In 1998, exposure to military sonar was postulated as the cause of a beaked whale stranding event in Greece in 1996. Similar events have occurred in the Bahama Islands in 2000, Madeira in 2002 and the Canary Islands in 2002," the report states. Since the early 1960s, when the Navy's mid-frequency tactical sonar was first deployed and the use of the system began, more than 40 mass strandings of Cuvier's beaked whales have been reported worldwide, some together with naval maneuvers. While the National Marine Fisheries Service (NMFS) report on whale strandings says that the numbers of strandings attributed to human generated sound are relatively minimal, the CCC study points out that most cases of strandings studied by the NMFS fail to consider anthropomorphic sound, like that generated by the Navy's mid-frequency sonar, as a possible cause for strandings. Dr. Lindy Weilgart, who has been studying underwater acoustics and their relation to marine mammals since 1993, says the link between mid-frequency sonar and beaked whale strandings is indisputable, and death among exposed whales may happen regardless of stranding. According to Weilgart, "whales who have been discovered after being exposed to the sonar have bubbles in their organs that can lead to death within hours regardless of stranding." Scientists worry that many whales affected by the sonar may go undiscovered or unreported in light of evidence that some affected animals do not strand but die at sea. Whale carcasses sink quickly when they die at sea, leaving little evidence other then the absence of known and tracked whale pods. One well-documented disappearance of a whale population happened in the Bahamas in 2000, when up to 100 well-studied whales went missing after the use of mid-frequency sonar. Of these whales, only two have returned to the area, implying that the whales have either entirely abandoned the area, or died at sea. There is no definitive explanation for how mid-frequency sonar creates the deadly bubbles in whales. Weilgart says that there are two main theories of why this occurs: "One theory is that it is a behavior effect. Panicked whales may shoot up from great depth, causing decompression sickness, or stay down too long, leading to a nitrogen build up. "Another theory is that super-saturation of nitrogen present from the depth the whales dive to, and sound waves (from sonar) create bulbs that grow and cause hemorrhaging–the same way a soda fizzes shaked up." The CCC report on the effects of human-generated underwater noise recommends that the Navy use mitigation strategies to help protect whales, including seasonal and geographic exclusion, the establishment of marine reserves, and safe zones. Of these the Navy voluntarily sets safe zones of 200 yards for sonar use. If marine mammals are detected within the safe zone, active mid-frequency sonar will not be used. But detecting deep diving whales like the beaked whales is extremely difficult and only a low detection rate is likely to be achieved, Weilgart pointed out. "The best protective measure the Navy could take is to make sure there is no resident population (of whales) in the area, by doing a good survey before," said Weilgart.