April 18, 2013
Seismic Ocean Surveys For Gas And Oil Could Kill 140,000 Marine Mammals
Lawrence LeBlond for redOrbit.com - Your Universe Online
Blasting sound waves through the ocean to the seafloor in search of fossil fuels may do more harm than good, according to environmentalists. But the US Department of Interior has been considering giving large oil and gas companies permission to do just that.
According to estimates, scores of marine mammals would be injured and possibly killed along the east coast if these companies follow through with their dangerous sonar pulses, which are expected to be 100,000 times more intense than the sound and energy produced by a jet engine.
The sonar blasts would be conducted with the use of seismic air guns that will search the ocean´s seafloor for signs of gas and oil pockets in the Atlantic Ocean. The companies plan to use the sound waves from Delaware to Florida, which would affect an estimated 138,500 whales and dolphins and could place a significant strain on the fishing and tourism industry.
Nonprofit group Oceana expressed in a report released Tuesday that seismic air guns would affect some 400,000 tourism, recreation and fishing jobs in Florida alone, potentially robbing the state of $15 billion in economic activity.
Oceana marine scientist and report author Matthew Huelsenbeck made this analogy: “Imagine a rocket being launched out of your living room every 10 seconds, 24 hours a day, for days to weeks at a time“¦ You could go deaf or be forced to move. That´s what it´s like for sea life that is subjected to seismic testing, but unlike in people, a deaf whale is a dead whale.”
Not only will the sonic blasting affect whales and dolphins, but sea turtles and fish could also succumb to the damaging effects of the intense air gun sound waves. Marine animals would endure temporary and permanent hearing loss, abandonment of habitat, mating and feeding disruptions, potential beach strandings and ultimately death. And these seismic tests would only be the first step. Once potential sites are found, offshore drilling is soon to follow, further harming the delicate marine ecosystem through leaks, spills and greenhouse gas emissions.
Huelsenbeck made it clear in the report that this seismic testing would place an unnecessary burden on the environment because Atlantic drilling cannot occur for at least the next five years in federally owned waters.
Still, the Interior Department´s Bureau of Ocean Energy Management (BOEM) is considering allowing the seismic surveys in federal waters, from three to 350 nautical miles out to sea. The surveys could, however, also cross into state waters closer to the shore. A decision on the allowance is expected no later than October.
If the seismic tests are allowed, survey ships would tow large air guns out to sea, where they would could be used to produce deafening sound created by the extreme pressure of compressed air bubbles. Hydrophones near the surface would record the sound that bounces back from the ocean bottom, revealing 3D images of the formations on the seafloor and below that could be hints of fossil fuel deposits.
But in an environmental study released last year, researchers described alternative ways to conduct offshore tests that would ensure the safety of marine mammals, sea turtles and other marine sea life. The study suggested that a six-mile area should be closed off during the main turtle nesting season and an additional 20 miles out could be made off-limits to sound surveys during whale migration, reported Jim Waymer of Florida Today.
“Most research revolves around sound impacts on marine mammals. The impacts on sea turtles are less clear. Sea turtles don´t have ear drums or external ears, but their auditory sense is adapted to vibrations in the water,” wrote Waymer.
Oceana´s goal is to get the government to phase out seismic air gun testing in federal waters altogether and do more to promote renewable energy. Huelsenbeck noted that our continued reliance on oil and oil exploration, will just “keep us more addicted to fossil fuels.”