Protecting Ocean Ecosystems

The Harmful Underwater Search for Oil and Gas

North Atlantic Right Whale skim feeding in Cape Cod Bay. Photo by Brian Skerry.

Imagine that for a month, each day, every ten minutes the world would go black with an explosion of dynamite. You could not see or hear anything. When the blackness and silence lifted, you would be disoriented, the people around you would be different, and food would be less available. How would you respond?

For marine organisms, this scenario is not something out of a doomsday movie but the reality of seismic testing. Seismic testing is a marine exploration technique that uses intense, low-frequency vibration signals which are directed into the seabed through an array of air guns. The feedback from the vibrations produces an image of the sea floor that is used for geographic mapping, military purposes, and locating offshore oil and gas.

A new study published in Nature describes how seismic testing has greater and more widespread ecosystem impacts than previously known. Past research has focused on the detrimental impacts for marine mammals and commercially important fish, but the Nature study revealed that seismic testing has the potential to decimate phytoplankton populations – the foundation of the marine food chain.

The study revealed that after a single cannon blast local phytoplankton populations decreased in abundance by 98%. All krill larvae was killed. All from one single blast. True seismic testing takes months, involving multiple canyons repeatedly fired every day.

This is the first study to look at the impacts of seismic testing on plankton, though previous studies have looked at its impact on other organisms. For example, whales use the same low-frequency vibrations for communication, movement and mating. During and after seismic testing, whales experience affected behavior, such as trouble mating and a decrease in appetite, as well as communication issues and hearing loss. Behavioral and pathological impacts on fish and fish eggs have been reported, and other studies have demonstrated significant developmental impacts on shellfish larvae.

Ocean noise is so detrimental because marine organisms rely on vibrations in the water for moving, mating, locating prey and “seeing” the underwater world. When seismic testing occurs, organisms are cut off from their surroundings and as a result development slows, long-term stress occurs, and the health of ecosystem greatly suffers.

Seismic testing has been justified by the constant need to explore for non-renewable resources or underwater oil and gas reserves, but the Nature study illustrates a new cost that needs to be considered. In addition to upper level food chain effects, the effects on plankton could have wide impacts for the whole food chain, including for many commercially-valuable species.

The current administration is considering to allow seismic testing off the Atlantic coast with known impacts to marine mammals and is also currently reviewing national marine sanctuaries and marine national monuments in all U.S. waters for potential opportunity costs associated with offshore oil and gas drilling. Coastal communities all along the east coast and throughout the country rely on our ocean resources for tourism, fisheries, recreation and food. The combined industries alone are worth several billion dollars. The New England Fishery Management Council even recently weighed in on the issue, writing a letter to the Administration requesting that the push for seismic testing be slowed until there is further data on its impacts to our fisheries and fishery resources.

Unlike many issues in today’s political scene, the opposition to seismic testing is bipartisan. A bipartisan bill was introduced in the U.S. House of Representatives that would ban seismic testing in the Atlantic and a similar Democrat-led bill was introduced in the Senate. House representatives from both sides of the aisle also sent a letter to Department of the Interior advocating for an “immediate halt to the permitting process.” The letter was signed by 103 representatives from both parties.

It is a foolhardy and short-sighted decision to allow seismic testing within the Atlantic Ocean. The public comment period regarding applications for seismic testing from 5 companies is open until July 21st. The Department of Commerce’s public comment period reviewing national marine sanctuaries and marine national monuments is open until July 26th. Don’t miss the chance to voice your opinion.


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