April 16, 2013

Whales and Dolphins At Risk from Seismic Surveys

From Yale Environment360, a summary of a new report from environmental group Oceana on the dangers of seismic testing for offshore energy:

The proposed use of seismic air guns in the search for offshore oil and gas reserves along the U.S. East Coast could injure or kill nearly 140,000 marine animals annually and disrupt the vital activities of other species, a new study says. The seismic testing, in which guns filled with compressed air are fired repeatedly over deep-sea target areas to provide energy companies an image of the deposits below, would threaten marine species of all sizes, from tiny fish eggs to large whales, according to an analysis by the conservation group Oceana. The group said that the powerful air gun blasts, which it describes as “100,000 times more intense than a jet engine,” could disturb the breathing, feeding, and mating habits for dolphins and whales and cause injury or death to endangered species such as the North Atlantic right whale. The analysis comes as the U.S. Interior Department’s Bureau of Ocean Energy Management completes an environmental study on the potential effects of seismic activities from Delaware to Florida. Oil industry officials point to other research that shows seismic testing is unlikely to threaten marine mammals.
The industry case, with some rebuttals by Oceana, is given in this longer report by Jennifer A. Diouhy at Fuelfix 

Industry representatives note that seismic technology has advanced dramatically in recent years — one reason that oil companies are eager for a look at data from the East Coast, where research is decades old. Geophysical survey companies also can tailor the timing of their studies to avoid animal migrations and minimize disruption. 

Industry officials also point to research that shows slim prospects of physical harm to marine life from seismic surveys. For example, during a 2012 study by scientists in San Diego that aimed studying the way marine mammals experience temporary losses in hearing sensitivity, the researchers could not induce the problem after exposing a dolphin to 10 impulses from an air gun. “None of the dolphins has exhibited significant behavioral reactions,” the scientists concluded. “These data suggest that the potential for seismic surveys using air guns to cause auditory effects on dolphins and similar delphiniums may be lower than previously predicted.” 

Chip Gill, the president of the International Association of Geophysical Contractors, stressed that seismic analysis helps boost the odds that oil and gas companies will drill promising wells — rather than dry holes — effectively limiting the industry’s potential footprint. “We used to explore with a drill bit,” Gill said. “There’s a strong argument that seismic surveys could be the preferred environmental tool.” 

Oceana recommends federal regulators require geophysical contractors adopt minimizing techniques, if they allow any seismic research along the East Coast. That could include use of less-disruptive seismic technology — not dependent on air guns — even though it may be a few years away. “If seismic testing is going to occur, (the Department of Interior) should require it be done using the least harmful technology available,” Oceana said in its report. Regulators also “should permanently close large areas to seismic surveying and drilling to protect vulnerable habitats and species.” 

Marine biologists say the government statistics don’t capture the potential damage, some of which manifests slowly over time. “For marine mammals that are more sensitive to sound and depend greatly on their hearing, such as whales and dolphins, the airgun noise can be a severe threat,” Oceana said. In the case of low-frequency noise, “the sound can travel thousands of miles away from the airgun source, interrupting whale calls and altering their behavior even at great distances. Fin and humpback whales in a 100,000 square mile area stopped singing in the North Atlantic because of such noise, and bowhead whales have abandoned their habitat because of it in Alaska.” 

Although the Obama administration’s five-year plan for selling offshore oil and gas leases through 2017 does not include any planned auctions of Atlantic waters, a new generation of seismic research could pave the way for future drilling in the region. Data indicating potential big untapped resources could add pressure for future administrations to lease Atlantic tracts and help plan any auctions in the area. The geological and geophysical surveys also would be used to dictate the siting of future renewable energy installations offshore and help pinpoint areas for sand and gravel mining.

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Jennifer A. Diouhy, "Seismic research on East Coast could harm 140,000 whales & dolphins," Fuelfix, April 16, 2013.

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