In June, conservation groups, government agencies and the geophysical industry settled a lawsuit over the use of seismic air guns in the gulf, putting some areas off limits for 30 months while officials conduct more tests, including some between March 1 and April 30 of each year, when dolphins are calving.
Gill said the industry “agreed to it because, operationally, it’s workable for us. A number of aspects of that settlement have no scientific basis behind them.”
Now attention is turning to the Mid- and South Atlantic, with energy companies applying to determine how much oil and gas might be available and conservation groups determined to stop them.
In June, the House approved an amendment offered by Rep. Scott Rigell (R-Va.) that would require BOEM to allow air gun testing in the Atlantic by Dec. 31. In January, Rep. Frank Pallone Jr. (D-N.J.) and Sen. Frank R. Lautenberg (D-N.J.) sent letters to Obama criticizing seismic air gun testing as the first step toward allowing offshore drilling, and Pallone questioned Jewell about it at a hearing in July.
“We don’t think drilling is safe, and we don’t want it expanded into the Atlantic,” said Matthew Huelsenbeck, a marine scientist for Oceana, the conservation group that is leading the fight against air guns in the Atlantic.
In its draft environmental impact statement, BOEM estimates that air-gun noise of 180 decibels might affect the feeding, migration or other behavior of nearly 1,000 sperm whales, 39 humpback whales and a few other cetaceans annually. It prediced that blasts of 160 decibels could affect 1.1 million bottlenose dolphins and hundreds of thousands of each of five other dolphin species.
Conservation groups said the impact would be much more dire, with effects including possible deafening of endangered whale species, such as the right whale, and injuring or killing of others. In the darkness beneath the ocean, Huelsenbeck said, whales and dolphins depend almost entirely on their hearing for survival.
Hearing loss is “a death sentence for a marine mammal,” he said. “It might not kill them right away. [But] they’re not going to be able to socialize, to find their pod, to find food.”
In laboratory experiments, researchers have seen temporary auditory injuries at 180 decibels, Scholik-Schlomer said, but it is difficult to know whether that translates to animals in the wild.
Gill said there is no evidence of any such harm occurring, despite the use of air guns around the world for the past 40 years. Vessels carry observers who must shut down the air guns if dolphins or whales are seen, and the volume of the devices is ramped up slowly, scaring sea creatures away before the noise reaches its peak.
If the goal is to shut down oil and gas exploration in favor of constructing wind turbines, Gill said, pile-driving for windmill construction will be louder than air guns.
Both sides point to a device that uses vibrations instead of sound for mapping, but Gill said it is not known whether it will be reliable.