Keep the Atlantic free of noisy oil exploration to protect whales, dolphins, fish and other marine life. That's the message of a letter signed by 75 scientists and sent last week to US President Barack Obama.
They fear that loud airgun blasting methods used to detect oil and gas deposits beneath the seabed will wreak havoc on marine life along the US Atlantic seaboard. Last month, the Obama administration announced that parts of the Atlantic coast would be opened up for drilling, with leases for oil and gas development to be awarded from 2017.
A framework to allow such "seismic testing" received the go-ahead last year from the US Department of the Interior, and nine applications to prospect are now being reviewed, pending environmental impact assessments. The scientists call on Obama to use his presidential powers to intervene and halt the testing program.
"The magnitude of the proposed seismic activity is likely to have significant, long-lasting and widespread impacts on the reproduction and survival of fish and marine mammal populations in the region, including the critically endangered North Atlantic right whale, of which only 500 remain," say the scientists, led by Christopher Clark of Cornell University.
"High-volume airguns… fire approximately every 10 to 12 seconds, often for weeks or months at a time, with sound almost as powerful as that produced by underwater chemical explosives," the letter says. These sounds will "disrupt activities essential to foraging and reproduction over vast ocean areas", because sound travels much further and more easily in water than in air. Some studies have found that seismic blasts cause physical harm to animals such as squid and octopuses.
Ocean of sound
"The ocean is a world of sound, and marine mammals and fish rely on it for feeding, breeding and maintaining social bonds," says Michael Jasny of the Natural Resources Defense Council, an environmental group in Washington DC, which backed the scientists' call.
According to Jasny, a study by the Norwegian government in 1996 showed that seismic testing made fish flee, with catch rates plummeting by between 40 and 80 per cent during the blasting period. Likewise, a study in the Gulf of Mexico in 2009 showed that foraging activity by tagged sperm whales dipped by 20 per cent while they were exposed to airgun noise.
The Department of the Interior, on the other hand, concluded that marine life would not be seriously disrupted even if the 13 million blasts it estimates will take place over six or seven years go ahead, a finding that Jasny disputes. "Each of those blasts could mean a lost foraging or breeding opportunity," he says.
If you would like to reuse any content from New Scientist, either in print or online, please contact the syndication department first for permission. New Scientist does not own rights to photos, but there are a variety of licensing options available for use of articles and graphics we own the copyright to.
No comments:
Post a Comment