Extremely loud air gun blasts have not been used to hunt for oil deposits in the mid and south Atlantic ocean for the last 30 years, but since the industrial practices of the ’80s are apparently in vogue again, on Wednesday the Trump administration restarted the application process to use seismic surveying. Environmentalists say the technology threatens surrounding deep sea ecosystems for thousands of kilometres.
Banned in some regions in January 2017 by President Obama, air guns are a prospecting tool for undersea resource extraction, used around the world since the digitisation of surveying in the 1960s. The technique uses sound waves to detect differences in the composition of Earth’s crust kilometres beneath the sea — a patch of oil bounces back a distinct sound when hit with the acoustic waves. To its credit, the technique replaced the use of exploding dynamite to detect underwater features.
“Seismic surveying helps a variety of federal and state partners better understand our nation’s offshore areas,” secretary of the interior Ryan Zinke said in a statement. “Allowing this scientific pursuit enables us to safely identify and evaluate resources that belong to the American people.”
In the same statement, Zinke claims that beyond oil deposits, seismic surveying can be used for “locating offshore hazards, siting of wind turbines, as well as offshore energy development”.
Proponents of the plan say that there is no environmental impact of seismic surveying. It’s been three decades since the technique was used in the protected regions of the Atlantic and technology has advanced, the Department of the Interior said in the statement.
According to the Bureau of Ocean Energy Management, “Seismic surveys are not expected to have significant impacts on marine mammal populations or the environment given the use of advanced technology and other safeguards that are currently required.”
But environmentalists, along with a growing body of scientific research, suggest the technique may be more damaging than we realise.
A study published in the April 2017 issue of Marine Policy documented the impacts of air guns on reef populations off the East Coast, and it found something kind of wild: About 78 per cent of the fish in range of the air gun blasts disappeared from the reef they called home.
During unrelated research in September 2014, University of North Carolina at Chapel Hill PhD candidate and study author Avery Paxton was told to leave the area while another research team proceeded with a seismic survey. It was dangerous for anyone to be in the water at the same time as the air guns were going off, which should have maybe been a sign.
But Paxton had the idea to leave cameras and sound recording equipment in the reef to catch the behaviour of fish during the testing. We already had data on the effects air gun blasts can have on marine mammals, but we had yet to look at how the practice affected fish populations.
The results were striking, with video evidence showing a huge number of fish hiding from the blasts and exiting the reef. Unfortunately, the researchers weren’t able to determine if the fish eventually returned, as by that point, the camera equipment’s batteries had been depleted. Either way, the disruption of the fish habitats could have serious consequences.
“These reefs are really important habitat to the fish of this area,” Paxton told Hakai Magazine. “They serve as nursery grounds and they’re places where the fish can eat and hide from predators.”
The Trump administration has yet to actually approve any new seismic surveys, but they have restarted the application process for six companies seeking permits to search for more oil off the eastern seaboard, including in a wide area stretching from the south of North Carolina to the East Coast of Florida. Previous objections to resource extraction in the region include the impact it would have on cetacean and sea turtle habitats.
Time will tell if any of the applications get approved, and what kind of ecological damage renewed seismic surveying will lead to. Unfortunately, it’s hard to imagine any evidence of environmental damage lessening the Trump administration’s appetite for oil.