The blowhole of a North Atlantic right whale is seen from the research vessel Shearwater's upper deck as the whale moves away from the boat in Cape Cod Bay. (Stephan Savoia/AP)

State attorneys general from Maine to South Carolina joined a lawsuit filed by conservationists seeking to block the Trump administration from allowing seismic testing in the Atlantic Ocean that could harm marine mammals and lead to drilling off the Eastern Seaboard for the first time in decades.

New York State Attorney Barbara D. Underwood (D) announced Thursday that the coalition of nine attorneys general moved to stop “the proposed use of air guns to survey the Atlantic Ocean floor for oil and gas” on the grounds that they will “expose whales, dolphins and porpoises to repeated sound blasts louder than 160 decibels,” threatening their health.

The attorneys general from Maryland, Virginia, North Carolina, Massachusetts, Delaware, Maine, Connecticut, New Jersey and New York are also opposed to the prospect of drilling for oil and natural gas off their shores.

“While the administration continues to place the interests of the fossil fuel industry ahead of our precious natural resources, attorneys general up and down the Atlantic coast will continue to fight these and other efforts to open waters off our shores to drilling for oil and gas,” Maryland Attorney General Brian E. Frosh (D) said in a statement.

States joined the lawsuit to seek an injunction and stop seismic mapping from moving forward, Frosh said, on the grounds that it violated the Endangered Species Act, the Marine Mammal Protection Act and other federal laws to conserve wildlife.

Underwood said Atlantic states are also united in a common fear: “We don’t need the next Deepwater Horizon off New York’s shores. We’ll fight in court to make sure it never happens,” she wrote in a tweet. The 2010 BP Deepwater Horizon explosion in the Gulf of Mexico resulted in the nation’s worst offshore oil spill.

The Trump administration proposed in January to offer oil and gas industry leases on nearly the entire U.S. outer continental shelf, an expansion that would be the largest in history. Governors in states along the Pacific and Atlantic coasts, along with state lawmakers and congressional delegations, stood in near-unanimous opposition.

Last month, NOAA Fisheries announced that five companies that want to map the Atlantic floor in the hope of finding large deposits of oil and natural gas were awarded “incidental take” permits that allow them to harm hundreds of animals while going about their work. The companies need only geological permits from the Bureau of Ocean Energy Management to proceed.

A week ago, several environmental groups sued the administration in federal court for granting the permits, saying NOAA Fisheries violated several federal laws that protect animals when it issued the permits.

Although NOAA Fisheries emphatically said it expected no animals to be harmed, the environmentalists disagreed. Dolphins and whales use echolocation to communicate and hunt, and some scientists say the blasts can damage their hearing.

The attorneys sided with the environmentalists. The seismic testing would threaten the “health and continued existence of hundreds of thousands of highly sensitive marine mammals, including multiple endangered or threatened species,” Underwood said in a statement.

Frosh noted in his statement that the sound blasts “can travel nearly 2,500 miles across the ocean, and can occur every ten seconds for weeks to months.”

A broader concern, Underwood said, was New York’s ocean economy, which, like other coastal Atlantic states, has thrived in the absence of oil exploration and production more than 50 years. Along the Gulf Coast, in contrast, thousands of wells have been drilled, with pipelines crisscrossing that basin for thousands of miles.

Seismic testing is “another step towards allowing offshore drilling — an action that could decimate New York’s $25 billion ocean economy, and the 350,000 jobs and $12 billion in wages it supports,” Underwood said.