The US Navy Friday claimed an exemption from legal restrictions on the use of active mid-frequency sonar, which environmental groups say can be deadly to whales and other marine mammals.
It said the Defense Department authorized the six-month "national defense" exemption from the Marine Mammal Protection Act after environmental organizations filed suit to try to stop the navy from using sonar in an exercise off Hawaii.
"Under the national defense exemption, the navy will not be required to seek permits for activities under MMPA during a six-month period," the navy said.
The National Oceanic and Atmospheric Administration on Tuesday granted the navy a permit to "take" as many as 25,000 protected marine mammals by blasting mid-frequency sonar in an exercise called Pacific Rim in Hawaii.
Environmental organizations responded with a lawsuit Wednesday that argued it was unlawful to grant a permit for activity that can harm protected mammals such as whales and dolphins.
