Gulf of Mexico Whales, Dolphins Protected from Industry’s High-Intensity Airgun Surveys in Landmark Agreement

Environmental coalition reaches legal settlement with feds and oil and gas industry


Steve Roady, Earthjustice, (202) 667-4500


Jessica Lass, NRDC, (310) 434-2300


Michael Jasny, NRDC, (310) 876-8525


Miyoko Sakashita, CBD, (415) 632-5308


Cynthia Sarthou, GRN, (504) 525-1528, ext. 202

Today, a coalition of conservation groups (the Natural Resources Defense Council, the Gulf Restoration Network, the Center for Biological Diversity, and the Sierra Club) announce a major settlement agreement with the Department of the Interior and oil and gas industry representatives, to protect whales and dolphins in the Gulf of Mexico from high-intensity airgun surveys. The settlement requires new safeguards, including putting biologically important areas off-limits, expanding protections to additional at-risk species, and requiring the use of listening detection devices to better ensure surveys do not injure endangered sperm whales. The agreement was filed in the case of NRDC v. Jewell, in U.S. District Court for the Eastern District of Louisiana.

“Today’s agreement is a landmark for marine mammal protection in the Gulf,” said Michael Jasny, Director of NRDC’s Marine Mammal Protection Project. “For years this problem has languished, even as the threat posed by the industry’s widespread, disruptive activity has become clearer and clearer.”

To search for oil and gas, the industry typically uses arrays of high-powered airguns that release intense blasts of compressed air into the water every 10–12 seconds, for weeks or months at a time. The noise they produce is almost as intense as dynamite, which airguns replaced in the mid-1950s. Each year industry routinely conducts dozens of “seismic” exploration surveys in the northern Gulf, one of the most highly prospected bodies of water on the planet.

“These super-loud airblasts hurt whales and dolphins so we’re glad to know the oil industry and federal government will take important steps to protect these vulnerable animals,” said Miyoko Sakashita, Oceans Director at the Center for Biological Diversity. “The seismic surveys sound like an underwater explosion, causing deafness and stress that can disrupt whales’ behaviors and even lead to strandings.”

The conservation groups’ lawsuit in 2010 asserted that the Interior Department failed to satisfy basic requirements of the Marine Mammal Protection Act and Endangered Species Act in permitting seismic exploration in the Gulf, and failed to prepare an environmental impact statement, which the National Oceanic and Atmospheric Administration (NOAA) has said is necessary. Today’s agreement, which must be approved by the district court, extends substantial new protections to the region’s vulnerable whale and dolphin populations while environmental review is completed.

Whales, dolphins, and other ocean species depend on sound to feed, mate, navigate, maintain social bonds, and undertake other activities essential to their survival. Airgun noise is loud enough to mask whale calls over thousands of miles, destroying their capacity to communicate and breed. It has been shown to drive whales to go silent, abandon their habitat and cease foraging, again over larger areas of ocean; closer in, it can cause hearing loss, injury, and potentially death.

The industry’s airgun surveys are known to affect marine mammal populations within the spill zone of the Deepwater Horizon disaster. These populations include the Gulf’s coastal bottlenose dolphins, which have undergone a severe die-off since the spill; its resident population of Bryde’s whales, of which fewer than 50 individuals are believed to remain; and its small population of sperm whales, whose nursery in Mississippi Canyon was ground zero for the spill. In 2009, an Interior Department study found that Gulf sperm whales subjected to even moderate amounts of airgun noise appeared to lose almost 20 percent of their foraging ability—a result that could help explain why the population hasn’t recovered from whaling.

“The BP drilling disaster provided graphic images of oiled marine mammal carcasses, delivering tragic proof of the harm oil companies can do to Gulf wildlife by cutting corners,” said Cynthia Sarthou, Executive Director of Gulf Restoration Network, which was represented by Earthjustice in the litigation. “This agreement won’t magically make drilling safer, but it will increase the chances that our amazing whales and dolphins can continue to recover. I think the dolphins are doing backflips today.”

“The settlement not only secures new protections for whales and dolphins harmed by deafening airguns, but also establishes a process for investigating alternatives to airgun surveys,” said Ellen Medlin, Associate Attorney with the Sierra Club. “As a result, the settlement not only delivers immediate benefits for Gulf marine mammals, but also takes the first step towards a long-term solution.”

The settlement requires:

  • Additional protections for marine mammals while the government undertakes a programmatic environmental review of seismic exploration in the Gulf.
  • A prohibition on airgun blasting in biologically important areas, such as the DeSoto Canyon, which is important for sperm whales and critical to Bryde’s whales, the Gulf’s only resident population of large baleen whales;
  • A prohibition on airgun exploration in coastal waters during the main calving season for bottlenose dolphins;
  • Mandatory minimum separation distances between surveys;
  • Extension of the government’s existing mitigation measures to apply everywhere in the Gulf and to cover endangered manatees as well as whales;
  • Mandatory use of passive acoustic listening devices to detect and avoid marine mammals during times of reduced visibility.
  • A multi-year research and development project, to be undertaken by industry, to develop and field test an alternative to airguns known as marine vibroseis that has the potential to substantially reduce many of the environmental impacts of seismic activity.
  • A Bureau of Ocean Energy Management evaluation of new standards, to ensure that airgun surveys are not unnecessarily duplicative and generate the least practicable amount of sound for a given project.

The lawsuit was launched in June 2010 following the Deepwater Horizon oil disaster, which spilled 5 million barrels of oil into the Gulf of Mexico. The settlement does not address any of the parties’ active litigation against the Department of the Interior challenging a series of oil and gas lease sales in the region.

Related Video:
Airgun in Action: This brief clip showing a single airgun going off in a test pool. A large industrial array can include 18 airguns or more, all firing at once.

Related Document:

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