The Sound and the Fury

Navy officials say they’re making adjustments to minimize the problem. “We do care about the environment,” says Christina Adams, a Navy spokeswoman. “Since we established protective measures in January 2007, there’s been no stranding linked to the U.S. Navy as a result of sonar. The protective measures are working.”

The heart of the Navy’s new strategy is to look for whales through the eyes of trained sailors. If one is spotted within 1,000 yards (914 meters), the crew turns down the vessel’s sonar; within 200 yards (183 meters), they turn it off entirely.

But some researchers question the Navy’s approach. “If you have rough weather, if you have fog, if you have any chop or white caps, it makes it really, really difficult to see the animals,” says Parsons. In the best of circumstances, he says, there is only a one or two percent chance of detecting a beaked whale.

Other experts warn that sonar can maintain a harmful decibel level at distances far greater than the implemented “safe zone.” Depending on ocean conditions, sonar can reach roughly 175 decibels from 1,000 yards away.

The case that reached the U.S. Supreme Court in early October 2008 began as a lawsuit over a series of exercises planned off the southern coast of California. Environmental groups, led by the Natural Resources Defense Council, accused the Navy of not doing enough to protect marine mammals from sonar.

In its 5-4 decision in November 2008, the Supreme Court sided with the Navy, citing the military’s longstanding use of sonar in this region: over 40 years without “a documented episode of harm to a marine mammal,” according to the majority opinion written by Chief Justice John Roberts.

Independent observers, however, suggest the lack of documented incidents means little. The Navy’s use of sonar has evolved over the last 40 years to keep up with increasingly quieter fleets of submarines, notes Wright, formerly with NOAA. The focus of sonar use was in deeper, offshore waters through the end of the Cold War. Since the mid-1980’s, however, sonar has been employed in shallower, coastal areas – into which submarines are more likely to sneak. This makes strandings much more likely.

But this still doesn’t explain why strandings haven’t been observed over the last 20 years in southern California.

“Just because you didn’t see anything doesn’t mean it didn’t happen,” says Ragen of the Marine Mammal Commission. “The question is ‘Did you look?’ and ‘How well did you look?’”

In order for a whale to become a documented victim of Navy sonar, Ragen explains, a series of unlikely events would have to occur. The animal would typically have to die, float to the surface and wash up on a beach. Alternatively, a disoriented or severely injured whale would need to swim – or be carried by currents – to shore, and then die. Either case is especially unlikely in many parts of the world, including Southern California, where surface waters are driven away from the coast. Finally, the animal would have to be spotted, and evidence quickly obtained through an autopsy, before the body decomposes. And, again, scientists believe many of sonar’s deadly effects leave no physiological mark.

“All along, there are reasons why the number of animals that are actually documented and entered into records are underestimates,” says Ragen.

In the wake of the Supreme Court decision, all sides are moving ahead with their agendas. The Navy will continue with its $26 million-per-year marine mammal research program, but also plans to continue to “train like it fights” – with the use of sonar, according to Adams, the Navy spokeswoman.

Meanwhile, scientists are pursuing studies aimed at assessing the scope of the threat, as well as helping government agencies find new ways to safeguard whales and dolphins. “We are trying to develop mitigation measures that avoid specific situations, so that they don’t get hurt,” says Jim Lecky, the director of protected resources at NOAA Fisheries. Understanding where and when whales will be present, for example, could allow the Navy to steer clear of migrating mammals while still achieving their training goals. “It’s a balance of the two interests, between protecting marine mammals and keeping our sailors safe and effective in a war zone,” says Lecky.

For their part, environmentalists remain determined to press for stricter regulations.

“We are urging [the Navy] to take greater precautions, and we hope they do. If not, we’ll have to review our options – including further litigation,” says Zak Smith, a litigation fellow with the Natural Resources Defense Council. “There have been too many stranding events that have happened with sonar.”

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