Debate over seismic air guns should wait until science has spoken

(C) The Washington Post washingtonpost.com

By Editorial Board, Published: September 5

SEISMIC AIR guns are used to ascertain how much oil and gas lie under certain portions of the ocean floor. They’re towed behind ships that trace grids on the surface of the water, and they shoot blasts of compact air to the bottom of the ocean to track the reflected sounds. The problem is that those underwater blasts, at around 180 decibels, are louder than roaring jet engines, and they might harm ocean mammals, disrupting the feeding and migration patterns of whales, dolphins and other creatures.

In 2010, President Obama cleared the way for opening some 330,000 square miles of ocean off the East Coast, from the Delaware Bay to Florida’s Cape Canaveral, to exploration for oil and gas, of which there’s likely an enormous amount. As The Post’s Lenny Bernstein reported recently, the Bureau of Ocean Energy Management (BOEM) estimates that there are some 3.3 billion barrels of oil and 3.1 trillion cubic feet of natural gas off the East Coast, and those figures are based on data collected using outdated technology. The use of seismic guns has become a contentious issue among oil companies, conservationists and members of Congress since the Interior Department announced in March 2012 that it planned to allow them in the Atlantic.

In the Gulf of Mexico, a lawsuit over the use of the guns was settled in June with an agreement delaying their use for 30 months while officials further investigate their effects. But that same month, the House approved an amendment proposed by Rep. Scott Rigell (R-Va.) to require the BOEM to allow oil companies to test seismic air guns in the Atlantic as early as December. Proponents of the testing insist that the guns will find far more oil off the East Coast than is known to exist. In the gulf, seismic testing in 2011 revealed five times the oil reserves that had been detected by other methods.

Conservationists claim that using the guns off the East Coast would create a “war zone” for whales and dolphins. Some lawmakers, including Rep. Frank Pallone Jr. (D-N.J.) and the late Sen. Frank R. Lautenberg (D-N.J.), have complained to Mr. Obama that seismic air gun testing is only the first step toward a full embrace of offshore drilling.

The truth is that the battle is premature. Apart from the studies underway in the Gulf of Mexico, the government is updating its standards on noise levels that aren’t harmful to ocean life. The National Oceanic and Atmospheric Administration expects to complete them by the end of this year or the beginning of next. The risks of seismic air guns will be clearer then; only when science has spoken should any decision be made on their use off the Atlantic coast.

sperm whales and BP horizon

A technique that monitors whales through the sounds they emit has answered a key issue raised by the explosion of the Deepwater Horizon oil rig in the Gulf of Mexico two years ago this month. The sound-monitoring technique revealed that sperm whales retreated from the immediate area around the spill caused by the explosion.

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Azmy S. Ackleh, George E. Ioup, Juliette W. Ioup, Baoling Ma, Joal J. Newcomb, Nabendu Pal, Natalia A. Sidorovskaia, and Christopher Tienmann. 2012. Assessing the Deepwater Horizon oil spill impact on marine mammal population through acoustics: Endangered sperm whales. J. Acoust. Soc. Am. Volume 131, Issue 3, pp. 2306-2314.

Abstract – Long-term monitoring of endangered species abundance based on acoustic recordings has not yet been pursued. This paper reports the first attempt to use multi-year passive acoustic data to study the impact of the Deepwater Horizon oil spill on the population of endangered sperm whales. Prior to the spill the Littoral Acoustic Demonstration Center (LADC) collected acoustic recordings near the spill site in 2007. These baseline data now provide a unique opportunity to better understand how the oil spill affected marine mammals in the Gulf of Mexico. In September 2010, LADC redeployed recording buoys at previously used locations 9, 25, and 50 miles away from the incident site. A statistical methodology that provides point and interval estimates of the abundance of the sperm whale population at the two nearest sites is presented. A comparison of the 2007 and the 2010 recordings shows a decrease in acoustic activity and abundance of sperm whales at the 9-mile site by a factor of 2, whereas acoustic activity and abundance at the 25-mile site has clearly increased. This indicates that some sperm whales may have relocated farther away from the spill. Follow-up experiments will be important for understanding long-term impact.