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The U.S. Navy is planning to ramp up training activities off California and Hawaii. But that has rekindled a battle over Navy sonar, which is known to harm marine mammals. From member station KQED, Lauren Sommer reports.
LAUREN SOMMER, BYLINE: We humans are visual creatures and for good reason. If someone is far away, you can usually see them before you hear them. Underwater, it's the opposite.
BRANDON SOUTHALL: The physical environment of the ocean really favors the use of sound, and the animals have evolved accordingly.
SOMMER: Brandon Southall is a marine scientist affiliated with the University of California, Santa Cruz. And for the last few years, he's been recording whales off the California coast. A blue whale communicates with these deep rumblings.
SOUTHALL: Some of these low-frequency sounds can be picked up hundreds of miles away.
SOMMER: Sound travels four times faster underwater than it does in air, explains Southall. It also helps some dolphins and whales find things through echolocation. Navy sonar technology is based on the same idea, but ships use different sounds.
Sonar can be four times louder than a whale call. Southall and his team have seen blue whales and beaked whales stop feeding because of sonar, work that's partially funded by the Navy. Sonar can also cause temporary or permanent hearing loss and, in rare cases, has been connected with whale deaths.
ALEX STONE: We absolutely share the concern about protecting marine mammals.
SOMMER: Alex Stone is an environmental program manager with the Navy's Pacific Fleet. The fleet is looking to increase the training they've done for years off Southern California and Hawaii, where ship crews are trained to look for underwater hazards and submarines. Prepping for submarine warfare might sound a little retro, like something from the Cold War, but Stone says the threats are still out there.
STONE: There's been a proliferation of these very quiet, inexpensive diesel-electric submarines that a lot of countries have now.
SOMMER: Including North Korea, he says. The Navy's own analysis shows the sonar training will harm whales, dolphins and marine mammals. That's why Stone says there are lookouts on the ships who stop training if whales are spotted.
STONE: We think that the mitigation measures are effective, but it's true. I mean, you're never going to see every marine mammal that's there.
MICHAEL JASNY: We now know that beaked whales off California are declining precipitously. We know that blue whales aren't recovering.
SOMMER: Michael Jasny of the Natural Resources Defense Council says the Navy should avoid key areas like gray whale migration routes and the summer feeding grounds of endangered blue and fin whales.
JASNY: Southern California is a globally important feeding habitat for them. It should be elementary common sense to avoid the core feeding habitat of blue whales.
SOMMER: The state of California came to the same conclusion.
UNIDENTIFIED WOMAN: I will open the public hearing and call the Navy.
SOMMER: The California Coastal Commission addressed the Navy's training request earlier this year, where staffer Mark Delaplaine showed a map of sensitive areas.
MARK DELAPLAINE: The blue shades are the blue whale seasonal areas we would like to see them avoid, and the yellow are the fin whale areas.
SOMMER: The Navy's Alex Stone said avoiding specific areas just wouldn't work.
STONE: We rely on this large area. And when you start to segment it in little areas where you can't go here, can't go there, it really affects the training realism.
SOMMER: Five years ago, California made the same request. But the Navy doesn't have to get approval from state officials and it went ahead with the training anyway, saying national security was at stake. The Navy does need approval from federal wildlife officials with the National Marine Fisheries Service. That agency is expected to decide later this year. For NPR News, I'm Lauren Sommer in San Francisco.
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