Over the next seven years, the U.S. Navy estimates its ships will injure or kill just two whales in collisions as it tests and trains in Hawaiian waters, and it concluded those exercises won’t significantly harm local marine mammal populations, many of which are endangered.
However, the Navy also estimates the readiness exercises, which include sonar testing and underwater explosions, will cause more than 3 million instances of disrupted behavior, hearing loss or injury to whale and dolphin species plus monk seals in Hawaii alone.
That has local conservation groups worried that the Navy’s detailed report on its latest multi-year training plan is downplaying the true impacts on vulnerable marine mammals that already face growing extinction threats in Pacific training areas off of Hawaii and California.
“If whales are getting hammered by sonar and it’s during an important breeding or feeding season, it could ultimately affect their ability to have enough energy to feed their young or find food,” said Kylie Wager Cruz, a senior attorney with the environmental legal advocacy nonprofit Earthjustice.
“There’s a major lack of consideration,” she added,” of how those types of behavioral impacts could ultimately have a greater impact beyond just vessel strikes.”
The Navy, Cruz said, didn’t consider how its training exercises add to the harm caused by other factors, most notably collisions with major shipping vessels that kill dozens of endangered whales in the eastern Pacific each year. Environmental law requires the Navy to do that, she said, but “they’re only looking at their own take,” or harm.
The Navy, in a statement earlier this month, said it “committed to the maximum level of mitigation measures” that it practically could to curb environmental damage while maintaining its military readiness in the years ahead. The plan also covers some Coast Guard operations.
Federal fishery officials recently approved the plan, granting the Navy the necessary exemptions under the Marine Mammal Protection Act to proceed despite the harms. It’s at least the third time that the Navy has had to complete an environmental impact report and seek those exemptions to test and train off Hawaii and California.
In a statement Monday, a U.S. Pacific Fleet spokesperson said the Navy and fishery officials did consider “reasonably foreseeable cumulative effects” — the Navy’s exercises plus unrelated harmful impacts — to the extent it was required to do so under federal environmental law.
Fishery officials didn’t weigh those unrelated impacts, the statement said, in determining that the Navy’s activities would have a negligible impact on marine mammals and other animals.
Limited Protections
The report covers the impacts to some 39 marine mammal species, including eight that are endangered, plus a host of other birds, turtles and other species that inhabit those waters.
The Navy says it will limit use of some of its most intense sonar equipment in designated “mitigation areas” around Hawaii island and Maui Nui to better protect humpback whales and other species from exposure. Specifically, it says it won’t use its more intense ship-mounted sonar in those areas during the whales’ Nov. 15 to April 15 breeding season, and it won’t use those systems there for more than 300 hours a year.
However, outside of those mitigation zones the Navy report lists 11 additional areas that are biologically important to other marine mammals species, including spinner and bottle-nosed dolphins, false killer whales, short-finned pilot whales and dwarf sperm whales.
Those biologically important areas encompass all the waters around the main Hawaiian islands, and based on the Navy’s report they won’t benefit from the same sonar limits.
For the Hawaii bottle-nosed dolphins, the Navy estimates its acoustic and explosives exercises will disrupt that species’ feeding, breeding and other behaviors more than 310,000 times, plus muffle their hearing nearly 39,000 times and cause as many as three deaths. The report says the other species will see similar disruptions.
In its statement Monday, U.S. Pacific Fleet said the Navy considered the extent to which marine mammals would be affected while still allowing crews to train effectively in setting those mitigation zones.
Exactly how the Navy’s numbers compare to previous cycles are difficult to say, Wager Cruz and others said, because the ocean area and total years covered by each report have changed.
Nonetheless, the instances in which its Pacific training might harm or kill a marine mammal appear to be climbing.
In 2018, for instance, a press release from the nonprofit Center For Biological Diversity stated that the Navy’s Pacific training in Hawaii and Southern California would harm marine mammals an estimated 12.5 million times over a five-year period.
This month, the center put out a similar release stating that the Navy’s training would harm marine mammals across Hawaii plus Northern and Southern California an estimated 35 million times over a seven-year period.
“There’s large swaths of area that don’t get any mitigation,” Wager Cruz said. “I don’t think we’re asking for, like, everywhere is a prohibited area by any means, but I think that the military should take a harder look and see if they can do more.”
The Navy should also consider slowing its vessels to 10 knots during training exercises to help avoid the collisions that often kill endangered whales off the California Coast, Cruz said.
In its response, U.S. Pacific Fleet said the Navy “seriously considered” whether it could slow its ships down but concluded those suggestions were impracticable, largely due to the impacts on its mission.
Hawaii-based Matson two years ago joined the other major companies who’ve pledged to slow their vessels to those speeds during whale season in the shipping lanes where dozens of endangered blue, fin and humpback whales are estimated to be killed each year.
Those numbers have to be significantly reduced, researchers say, if the species are to make a comeback.
“There are ways to minimize harm,” Center for Biological Diversity Hawaii and Pacific Islands Director Maxx Phillips added in a statement, “and protect our natural heritage and national security at the same time.”