Protect Marine Mammals from Ocean Noise

People often think of the sea as a silent world, but in reality, it's full of sound. Because sound travels much faster and farther in salt water than in the air, whales and other marine mammals depend on their hearing for many of life's most basic functions—foraging, finding a mate, avoiding predators, communicating, and navigating their way through the vast waters. In this audio-focused environment, manmade noises are a major threat. They drown out the sounds that marine mammals rely on, causing an array of problems, from mass mortalities to chronic, debilitating harm of specific populations.

A humpback whale mother and calf Barb_Malc/iStock

NRDC's pioneering work has forced major noise polluters, such as the U.S. Navy and oil and gas industry, to comply with environmental laws and has protected some of the most sensitive marine mammal habitat off the coasts of California and Alaska, in the Gulf of Mexico, and elsewhere. We're now focused on grappling with the problem's mounting cumulative impacts across the globe by establishing regional strategies and promoting noise-reducing technologies to combat the increasing industrial use of the sea.

Commercial shipping is the leading contributor to low-frequency ocean noise worldwide, weakening the ability of blue, fin, and other endangered great whales to forage and breed in virtually every ocean basin on the planet. Biologists have likened it to smog because of the way it shrinks the perceptual world of whales, fish, and other marine life. In 2014, after a six-year campaign, NRDC pushed the International Maritime Organization to establish ship-quieting guidelines for commercial ships. Now we are partnering with progressive shipping lines on compliance, developing incentive systems with green-certification societies and ports in North America and Europe, and lobbying the U.S. and other governments for tax incentives and other policies that support noise reduction—all critical steps to transforming industry practice.

We have also pushed back against seismic exploration for offshore oil and gas drilling, which involves the use of high-powered air guns that blast compressed air about every 12 seconds for weeks to months at a time. Not only does the intense pounding mask whale calls over vast stretches of ocean, it causes commercial species of fish to scatter, leading fisherman all over the world to seek compensation for their losses. After litigation, we reached a landmark settlement agreement over exploration in the Gulf of Mexico, the most heavily prospected body of water on the planet, that included closure areas for threatened species and multi-year funding for the development of safer alternatives to airguns. NRDC is now working to achieve protection for the Atlantic, the Arctic, Cook Inlet, and other regions; to establish a long-term cap on exploration activity in the Gulf of Mexico; and to accelerate the development and use of alternative technologies that significantly reduce the industry’s environmental footprint.

NRDC has worked for more than a decade to mitigate the impacts from high-intensity naval sonar, which has been linked to mass whale standings and deaths around the world. Now biologists are concerned that navy ranges may have become population sinks for some whale species that are drawn there but unable to forage or reproduce. In the spring of 2015, a federal court ruled in our favor when we challenged navy sonar training off the coasts of southern California and Hawaii—two of the navy's largest ranges, which include important habitat for endangered blue whales and sensitive beaked whales as well as dolphins. In September 2015, we reached an agreement with the navy to stop the use of sonar and explosives there. Now we are working to permanently protect those areas and establish similar sonar-exclusion areas in the Atlantic, Pacific Northwest, and Gulf of Alaska.

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