The Center for Biological Diversity signaled its intent on Monday to file a lawsuit unless remedial actions are taken in the wake of the deaths of two fin whales dislodged from the hull of an Australian naval vessel during a training exercise at Naval Base San Diego.
In a letter sent Monday to various government officials, the nonprofit organization said it would pursue litigation unless the U.S. Navy and National Marine Fisheries Service re-examine the impacts of conducting training activities in the Pacific Ocean. The Fisheries Service was also asked to re-examine its determination that the U.S. Navy's activities in the area would have a negligible impact on endangered whales and other marine mammals.
The letter was sent in connection with the deaths of two whales -- likely a mother and her calf, according to the center -- who were found as the HMAS Sydney docked at Naval Base San Diego on May 8. The Sydney has been conducting joint exercises with the U.S. Navy since April.
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It's unclear where the ship, which, according to the Australian Navy, is "equipped with advanced combat systems, providing the ship with layered offensive and defensive capabilities to counter conventional and asymmetric threats" -- came in contact with the marine mammals, though it is known that the ship tied up to the dock on on the morning of May 9.
The center said vessel strikes are a leading cause of whale deaths in California, though it says the actual number of whales fatally struck by ships is vastly underreported.
In its letter, the center requested that the two latest deaths be taken into consideration to ensure better mitigation measures are put in place to protect marine life and that the agencies comply with Endangered Species Act regulations.
"These dead whales are grisly proof of the Navy's dire ongoing threat to vulnerable marine mammals," said Kristen Monsell, oceans legal director at the center. "We're asking the Biden Administration to find a better balance of marine protection with military readiness. Ship strikes are a top threat to endangered whales, but these tragedies can be avoided by slowing down through whale habitat."