US government approves use of underwater sonic cannons
The US government has announced its approval for the use of loud sonic cannons to find oil and gas deposits below the ocean floor along eastern coastal areas of America.
The approval opens a stretch of water from Delaware to Florida to exploration by energy companies preparing to apply for drilling leases in 2018. It also exposes whale, dolphins and other marine wildlife, such as turtles, to extreme levels of noise pollution under the water. The sonic cannons can fire pulses of sound 100 times louder than a jet engine through the water and down to the ocean floor. The decibel level is higher than that which would cause serious hearing damage in humans, and noise from sonic cannons has been recorded by underwater microphones over 2,000 miles from the source of the original blast.
Noise pollution threatens whale and dolphin populations, interrupting their normal behaviour, driving them away from areas important to their survival, and at worst injuring or sometimes even causing their deaths. For whales and dolphins, ‘listening’ is as important as ‘seeing’ is for humans, yet there are still no international regulations regarding noise pollution in the world’s seas.