WASHINGTON (Reuters) – The Trump administration on Friday gave five companies initial permission to conduct surveys of oil and gas deposits beneath a vast region off the U.S. East Coast using sound-wave blasts that conservationists say put whales and dolphins at risk.

The fisheries office of the National Oceanic and Atmospheric Administration issued permits to WesternGeco LLC, a subsidiary of Schlumberger Ltd, and CGG to harass but not kill marine mammals with air gun blasts in a region of the Atlantic from Delaware to Cape Canaveral, Florida.

The permits, that also went to ION GeoVentures, Spectrum Geo Inc and TGS-NOPEC Geophysical Company, are likely to increase tensions between the administration, which wants to open up offshore drilling, with governors from the East Coast who oppose it. President Donald Trump has espoused an “energy dominance” agenda to boost oil output for U.S. consumption and for exports.

Conservationists worry that marine mammals including the endangered North Atlantic right whale could be harmed and that the practice could lead to beachings of the species.

“Trump is essentially giving these companies permission to harass, harm and possibly even kill marine life … all in the pursuit of dirty and dangerous offshore oil,” said Diane Hoskins, a campaign director at the Oceana environmental group. “This is the first step toward offshore drilling in the Atlantic.”

NOAA said impacts on marine mammal populations would be limited. “We’ve been assured that the effects of the authorizations do not result in jeopardy to endangered or threatened species,” Donna Wieting, director of the NOAA fisheries office of protected resources, told reporters in a teleconference.

Benjamin Laws, a NOAA fisheries biologist, said the permits require protections for right whales in places they are expected to be present. The companies cannot conduct surveys within about 56 miles (90 km) from shore between Nov. 1 and April 30 in such areas, Laws said. If any right whales are spotted within just under a mile of a survey ship, the tests must be shut down, he added.

The administration of former President Barack Obama denied six permits two weeks before Trump became president, saying that the value of information from the air gun surveys would not outweigh potential risks to marine life.

If, as expected, the U.S. Bureau of Ocean Energy Management issues the companies further permitting, they will be able to conduct air gun surveys in the Atlantic for the first time since the 1980s.