BOSTON — The iconic North Atlantic right whale, a critically endangered species teetering at the brink of extinction, possibly faces a new threat, marine scientists say.

President Donald Trump wants to open the Atlantic coast to oil and gas exploration as part of a strategy to help the U.S. achieve "energy dominance" in the global market. His administration recently gave fossil-fuel exploration companies a green light to conduct seismic surveys across a stretch of ocean floor between Delaware and Florida.

While the testing won't be conducted off the New England coast, scientists say air guns used in the testing can harm or kill marine animals far away.

"The sound from seismic testing is so loud that it can literally travel for hundreds of miles," said Scott Kraus, vice president and chief scientist for marine mammals at the New England Aquarium. "It can disturb and kill mammals like whales, fish and even invertebrates like scallops, while displacing animals from areas of critical marine habitat."

Air guns are towed behind ships and send loud blasts of compressed air through the water, which then create seismic waves through the seabed. The reflected waves are measured to reveal information about buried oil and gas deposits.

Blasts are repeated every 10 to 12 seconds during testing, which in some cases can continue around the clock for days, according to industry groups.

Right whales, which number only about 411 worldwide, migrate each winter from feeding grounds off New England to calving grounds in the warmer waters off the southeast coast. Seismic testing could create more stress on the whales, scientists say, resulting in fewer births for a species that is already suffering from a lack of reproduction.

"There's a real possibility that the chronic noise from seismic activity could interfere with reproduction in right whales," Kraus said.

What's more, right whales and their offspring communicate using sound, and disruptions from acoustic testing could cause babies to get separated from mothers, he added.

Seeking energy sources

Existing federal policy keeps 94 percent of coastal waters off-limits to drilling. A five-year plan announced by the Trump administration would open 90 percent of the nation's offshore reserves to private development. The seismic testing is considered a precursor to issuing federal drilling permits for offshore exploration.

Among the areas proposed for drilling is Georges Bank, a shallow and turbulent fish spawning ground southeast of Cape Ann and about 100 miles east of Cape Cod.

Currently coastal drilling is only allowed off the coasts of Alabama, Louisiana, Mississippi, Texas, and parts of Alaska and California.

"The U.S. needs to know what energy resources exist off of our shores, and we are hopeful that permits for surveying for offshore oil and natural gas and a full national offshore leasing plan to explore and develop the outer continental shelf will move forward soon," said Reid Porter, spokesman for the American Petroleum Institute, a trade group.

Porter disputes that seismic testing will impact marine life, citing a 2014 report from the U.S. Bureau of Ocean Energy Management that there is "no documented scientific evidence of noise from air guns used in geological and geophysical seismic activities adversely affecting marine animal populations or coastal communities."

Survey ships will carry observers to listen and watch for marine life and alert operators of any protected species nearby, he said.

The oil and gas industry is "committed to improving the scientific understanding of the impacts of our operations on marine life, while responsibly producing oil and gas resources to meet our nation’s energy needs," he said.

Driven to the brink

Democratic governors along both coasts unanimously oppose drilling, as do a number of Republican governors, including Massachusetts Gov. Charlie Baker.

The Obama administration denied six permits for seismic testing weeks before Trump took office in 2017, citing concerns about the impact on wildlife and fisheries.

"We believe that the value of obtaining the geophysical and geological information from new air-gun seismic surveys in the Atlantic does not outweigh the potential risks of those surveys’ acoustic pulse impacts on marine life," said Abigail Ross Hopper, director of the Bureau of Ocean Energy Management at the time.

The same 2014 bureau report cited by supporters of oil and gas exploration estimated that nearly 2.5 million dolphins would be harassed or killed by seismic testing each year in the mid- and southern Atlantic while right whales, humpbacks and pilot whales would also be affected.

Driven to the brink of extinction in the 20th century by whalers, right whales are more recently at risk from ship collisions and entanglement in fishing gear. Scientists say the population of North Atlantic right whales could decline to levels not seen since 1990 in the next decade.

The world population was estimated at only 268 in the early-1990s before to rebounded to a recent high of 481 around 2010, according to the National Oceanic and Atmospheric Administration.

But the species has been hindered by poor reproduction and several years of high mortality, scientists say.

No new calves have been born this year, raising more doubt about the species’ future.

Last year, at least 17 right whales washed up dead in the U.S. and Canada, far outpacing five births.

"We can manage killing by ships and fishing gear, but the only way to manage reproduction is reduce the stress," Kraus said. "We need to give them every chance to have babies."

Trump's offshore drilling plans have already spurred legal challenges, including one filed Wednesday by environmental groups in South Carolina.

The lawsuit says the National Marine Fisheries Service violated the Marine Mammal Protection Act, the Endangered Species Act and the National Environmental Policy Act when it issued five permits for the use of seismic air guns.

"This action is unlawful and we’re going to stop it," Diane Hoskins, campaign director at the nonprofit group Oceana, said in a statement on the legal challenge. "The Trump administration’s rash decision to harm marine mammals hundreds of thousands of times in the hope of finding oil and gas is shortsighted and dangerous."

Christian M. Wade covers the Massachusetts Statehouse for North of Boston Media Group’s newspapers and websites. Email him at