Whales under threat as US approves seismic oil prospecting in Atlantic

• Sonic cannons to be used in ocean from Delaware to Florida

• Study estimates 138,000 sea creatures could be affected

Associated Press in St Augustine Beach, Florida

theguardian.com, Saturday 19 July 2014 15.34 BST

The Obama administration is reopening the eastern seaboard to offshore oil and gas exploration, approving seismic surveys using sonic cannons that can pinpoint energy deposits deep beneath the ocean floor.

Friday's announcement was the first real step towards what could be a transformation in coastal states, creating thousands of jobs to support a new energy infrastructure. But it dismayed environmentalists and people who owe their livelihoods to fisheries and tourism.

The cannons create noise pollution in waters shared by whales, dolphins and turtles, sending sound waves many times louder than a jet engine reverberating through the deep every 10 seconds for weeks at a time. Arguing that endangered species could be harmed was the environmental groups' best hope for extending a decades-old ban against drilling off the US Atlantic coast.

The Bureau of Ocean Energy Management acknowledged that thousands of sea creatures will be harmed even as it approved opening the outer continental shelf from Delaware to Florida to exploration. Energy companies need the data as they prepare to apply for drilling leases in 2018, when current congressional limits expire.

"The bureau's decision reflects a carefully analysed and balanced approach that will allow us to increase our understanding of potential offshore resources while protecting the human, marine, and coastal environments," the acting BOEM director, Walter Cruickshank, said in a statement.

Sonic cannons are already used in the western Gulf of Mexico, off Alaska and in other offshore oil operations around the world. They are towed behind boats, sending down pulses of sound that reverberate beneath the sea floor and rebound to the surface. Hydrophones capture the results, which computers translate into high-resolution, three-dimensional images.

"It's like a sonogram of the Earth," said Andy Radford, a petroleum engineer at the American Petroleum Institute, an oil and gas trade association in Washington DC. "You can't see the oil and gas, but you can see the structures in the Earth that might hold oil and gas."

The surveys can also map marine habitats and identify solid undersea flooring for wind energy turbines. But fossil fuel mostly funds this research, and corporations keep the data secret, disclosing it only to the government.

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