Last week the Makhanda High Court dismissed the application to halt @Shell ’s controversial seismic survey along the South African Wild Coast. The High Court judged in favour of the oil firm because of the financial cost of the delay and because the applicants had failed to prove that the survey would cause “irreparable harm”. The judgment allows Shell to begin firing extremely loud sound waves through the relatively untouched marine environment, which is home to whales, dolphins, seals and more than 2000 different species of fish.
During a seismic survey, ships (seismic vessels) equipped with seismic airguns and hydrophone streamers (acoustic sensor arrays) are used to visualize the layers beneath the seafloor to locate the best possible area for oil or gas drilling. To be clear, they are not only pinpointing the best locations; oil and gas companies do these surveys only if they fully expect to drill if they find the right spot – the surveys are rather costly. This means that high-pressure sound blasting is only the start of the campaign; drilling for oil in the protected marine environment will be next.
At 185dB in air (246dB in water; sound propagates much faster and further in water), seismic pulses are approximately 30.000x louder than a jet engine taking off (140dB). As a reference, our pain threshold is at 130dB, our eardrums rupture at 150dB, and our lethal threshold is approximately at 185dB – precisely what a seismic airgun is pumping into the water. Not once, but every 10 seconds, 24 hours a day for 5 months in a row. Pulses strong enough to visualize layers hidden 50km deep beneath Earth’s surface.
Studies have shown that seismic pulses cause significant disruption to the population levels of zooplankton, basically destroying the first link of the food chain. With small marine critters having nothing to eat, the whole ecosystem goes out of balance. Besides the fact that marine animals cannot navigate and communicate with each other, they can also suffer physically (mortality and tissue damage) and physiologically (stress).
This can not continue – #SaveTheWildCoast
@Seashepherd
@seachangeproject
@sealegacy
@greenpeaceafrica
@greenpeace
