Issues > Underwater Noise Pollution
|Sound is to underwater creatures as sight is to humans. Noise from the human world is disrupting life below the surface where almost every living creature depends on sound as a primary sense for mating, hunting, and survival. A racket of shipping traffic, oil exploration, seismic surveys, sonar, and other human activity combine in a deafening chorus that is increasingly dangerous to sea life.
How is our noise affecting underwater creatures?Although there are many naturally blind creatures, there is not a single known deaf vertebrate species. This fact stands in testament to our large reliance on sound as a world. Unlike light, which dissipates quickly underwater, sound can also travel farther and up to five times faster underwater, allowing animals to communicate over great distances.1
On land animals and humans alike know to move away from a loud or traumatic sound; the further we get, the more the sound dissipates. Underwater, we would not be so lucky. Sonar and ship noise can send a deafening tidal wave of noise for miles. It is difficult to pinpoint the origin or source of a particular sound and even harder to avoid or outrun it. Whales, dolphins and other marine mammals that have been caught in the wake of sonar have died of cerebral hemorrhaging or intentionally beached themselves in a desperate attempt to avoid the ear-splitting resonance.
Oceanographer Sylvia Earle described underwater noise, "like the death of a thousand cuts. Each sound in itself may not be a matter of critical concern, but taken all together, the noise from shipping, seismic surveys, and military activity is creating a totally different environment than existed even 50 years ago. That high level of noise is bound to have a hard, sweeping impact on life in the sea.”2
Underwater, as on land, we must do better to protect those resources we share. Most of us cannot imagine the violent intrusion created by a shipping barge passing overhead. Notwithstanding the need for compassion, with this new knowledge of sound in the underwater environment comes the responsibility to protect those animals and fish and creatures that cannot protect themselves. We have the intellect and the technology to develop better boats and better defense tactics that will enable us to be better stewards of the ocean environment.
1 University of Rhode Island. Office of Marine Programs. Discovery of Sound in the Sea. Why is sound important to marine animals?
2 Michael Jasney, Joel Reynolds, Cara Horowitz, Andrew Wetzler. Sounding the Depths II: The Rising Toll of Sonar, Shipping, and Industrial Ocean Noise on Marine Life. Executive Summary. Natural Resources Defense Council. November 2005.