The U.S. Navy estimates it inadvertently kills 155 whales and dolphins off the coasts of Hawaii and Southern California in five years. Its training exercises also injure some 2,000 marine animals over the same period.
On Monday, thanks to a pair of lawsuits brought by environmental groups Earthjustice and the Natural Resources Defense Council, the Navy agreed to limit its use of sonar and other harmful training activities in critical habitats for whales, dolphins and other marine mammals.
The settlement, finalized by a federal judge in Honolulu, reconciles a decade-old debate about the Navy's sonar practices.
The agreement includes limits or bans on mid-frequency active sonar and explosives in specified areas. Earthjustice attorney David Henkin said that, at great distances, sonar can disrupt feeding and communication of marine mammals. At closer distances, it can lead to deafness or even death.
In April, a federal judge ruled that the Navy severely underestimated the threat of its trainings to marine mammals.
Lt. Cmdr. Matt Knight, spokesman for the Navy's U.S. Pacific Fleet, said the service “faced the real possibility that the court would stop critically important training and testing.” By reaching a settlement, the Navy preserved key national security missions, he said.
“Recognizing our environmental responsibilities, the Navy has been, and will continue to be, good environmental stewards as we prepare for and conduct missions in support of our national security,” Knight said.
Rhea Suh, president of the Natural Resources Defense Council, said in a release that the settlement, which will remain in place until 2018, ensures the security of naval operations while reducing the hazard to marine life.
"Our Navy will be the better for this, and so will the oceans our sailors defend," Suh said.
Henkin said in a statement that the Navy, by agreeing to the settlement, "acknowledges that it doesn’t need to train in every square inch of the ocean and that it can take reasonable steps to reduce the deadly toll of its activities."
In Southern California, the Navy will no longer be able to use sonar in important habitats for beaked whales between Santa Catalina Island and San Nicolas Island, as well as in blue whale feeding areas near San Diego.
In Hawaii, the agreement prohibits sonar and explosives training on the eastern side of the Big Island and north of Molokai and Maui. The environmental groups say the restrictions will protect Hawaiian monk seals and small populations of toothed whales, including the endangered false killer whale.
The Natural Resources Defense Council called the settlement a "huge victory," but said it won’t end the advocacy group's fight to protect marine mammals from Navy sonar.
"We’ll now work to expand this success to the Navy’s other ranges ... and to make the protections we’ve achieved permanent for marine mammals off Southern California and Hawaii," spokeswoman Kimiko Martinez told HuffPost.
The Associated Press contributed to this report.
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