PROVIDENCE -- The U.S. Navy says it's doing more than ever to protect marine mammals from potential harm by explosives and sonar used in offshore training and testing, despite its plans to boost its use of sonar threefold in the coming years.
Over the next five years, the Navy will focus more on detection of enemy subs and mines, said Jene Nissen, the Atlantic fleet training and testing program manager. That means tripling the use of sonar that was allowed in 2009 under a five-year permit issued by the National Marine Fisheries Service.
Because this type of training has harmed whales, dolphins and seals in the past, the Navy is seeking a five-year reauthorization of a permit from the National Marine Fisheries Service, granting them an exemption from the Marine Mammal Protection Act of 1972. Navy researchers and officials held the first of five informational meetings Wednesday in Providence to gather public comment on their plan. The remaining meetings will be held in the Mid-Atlantic and Southern coastal states over the next two weeks.
Navy researchers utilized a new computer model that predicted an increase in the opportunities for whales, seals and dolphins to be harassed or harmed during Navy training, from 1.9 million potential impact events per year under the old permit to 2.1 million per year. The testing area covers 2.6 million square miles from Maine to the Gulf of Mexico. Testing of new ships and equipment could add another 1.8 million impact events. Possible effects on marine mammals vary from small behavioral changes to cessation of feeding on up to temporary and permanent hearing damage.
And even though he has devoted his life to the protection of marine mammals, Charles "Stormy" Mayo cast an appreciative and envious eye over a graphic depicting elements of a computer model that helped the Navy estimate how many marine mammals could be harmed by testing and training.
The director of right whale habitat studies at Provincetown's Center for Coastal Studies, Mayo traveled to the hearing to submit comments on the Navy's proposed plan. The model itself was a marvel, Mayo admitted. A team of more than two dozen biologists and computer programmers working at the Newport Naval Undersea Warfare Center combined the Navy's wealth of acoustic knowledge with marine mammal data, showing estimated densities of animals by location and season.
They ran 6,000 simulations during the past two years on the computer model, which can render a three-dimensional view of how sound behaves in water and how different species are affected.
But Mayo was even more appreciative of the attitude and depth of knowledge of the experts the Navy had assembled to research marine mammals and mitigate potential damage from sonar and explosives.
Nissen said the Navy spends $15 million to $20 million a year on marine mammal research and another $5 million annually on monitoring and survey work connected to its testing and training.
"Twenty years ago, you wouldn't have seen this level of sensitivity," Mayo said. He had worked with the shipping industry in recent years on how to reduce the chances their ships would hit right whales, the world's most endangered great whale, and thought the Navy was far more forthcoming and cooperative.
"To their credit, they are coming to us and talking about it," Mayo said.
That doesn't mean there is universal acceptance of the Navy's program, however. Mayo and Nissen said there are big information gaps in how sonar and explosives affect some species like the great whales, for instance. Some environmental organizations would like to see more emphasis on closing certain known gathering spots for testing at the times of year species are present in numbers.
U.S. Navy Marine Resource Specialist Sarah Bellau pointed out the impracticality of closing areas with dozens of varying species congregating at different spots in the ocean.
"What might be a hot spot for one species might not be for another," Bellau said. Instead, the Navy proposes to use trained lookouts to spot marine mammals in the water.
The strength of the sonar signal is reduced the closer they get to the vessel, she explained, and is shut down altogether for at least a half-hour, or until they leave the area, if they get within a few hundred yards. Passive acoustic devices also listen for the sounds of marine mammals underwater and aircraft fly over the area before training or testing begins.
Specific rules prohibiting certain testing also apply for the Great South Channel southeast of the Cape and Stellwagen Bank National Marine Sanctuary.