Human-caused noise pollution impacts sound-reliant species of whales and other marine life. Seismic mapping, shipping and boating traffic mask the acoustic communication systems they’re reliant on. 

When a strand of eight adult female beaked whales were found on the shores of the far-flung Aleutian Islands in Alaska, members of the National Oceanic and Atmospheric Administration response team were bewildered. The whales appeared to be healthy, with no major external injuries, but their presence was unusual. What was thought to be a rare occurrence in 2018 has turned out to be part of a recurring pattern. Marine Mammal Science published a study which revealed that since the original discovery of the species, Alaska has had 74 known beaked whale strandings in 42 separate events. 

Military and naval operations in the area were put to a halt in 1997 but the U.S. Geological Survey’s monitors at the Alaska Volcano Observatory have detected human-caused seismic survey activity along the islands. New research suggests that the surveys may have been involved in the mass stranding. Underwater sonic tests are only the latest example of ocean noise pollution cited by environmentalists. Growing concern has spurred research into the potential threats of human-made noise for marine life. 

During seismic surveys, blasts of compressed air produce pulses of sound that analyze the seafloor for natural resources. At 220-250 decibels, these seismic air guns are the loudest noise created by humans underwater, producing a sound louder than a Saturn V rocket during launch. According to an article in Nature, “in the five decades before 1950, researchers recorded just seven mass strandings; but from then to 2004, after the introduction of high-power sonar for naval operations, there were more than 120.”

During the Trump administration, a ban on offshore drilling was lifted and companies from Central Florida to the Northeast were granted permits to carry out seismic mapping for gas and oil exploration. Senior bioacoustics researcher at the Cornell Lab of Ornithology Christopher Clark has studied whale communication for 40 years. Clark described the noise produced from seismic mapping as a “living hell” for undersea life.

Another primary contributor to ocean noise is shipping traffic, both commercial and recreational. Between 1950 and 2000 ship traffic doubled, producing an increase in noise of about three decibels per decade. This has led to communication masking — a term used to describe the reduction in the area over which animals are able to acoustically communicate. Research shows that across species, the combination of noise contribution from commercial and recreational vessels led to a reduction in communication range of up to 82%. A recent study found that shipping noise has the potential to double by 2030, further limiting the distance whales and other marine life are able to communicate between.

In the marine ecosystem, where visibility is limited, acoustics are the primary form of communication. For whales, every aspect of their lives is dependent on sound. Many of their species are highly intelligent, social beings who communicate in clicks and songs, and are even known to have their own languages. Some whales and orcas are known to use echolocation, a natural sound wave sonar, to hunt and locate food. Noise masks their expressions between their families, affecting their ability to feed and care for their young, as well as their orientation and ability to detect prey or oncoming ships. 

In 1956, French oceanographer Jacues Cousteau released a documentary misleadingly titled The Silent World, that fed into the misconception of a quiet underwater seascape. Today we know that a healthy ocean isn’t a silent one. The ocean thrives on the familiar sounds of its natural world, sounds that marine life recognizes as home. Lead author ofThe Soundscape of The Anthropocene Ocean Carlos Duarte says that “The soundtrack of home is now hard to hear, and in many cases has disappeared.”

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Claire is a freelance journalist from Chicago, where she received her Bachelor’s of Communications from the University of Illinois. While living and studying in Paris, Claire wrote for the magazine, Toute La Culture. As a freelancer she contributes to travel guides for the up and coming brand, Thalby. She plans to take her skills to London, where she’ll pursue her Master’s of Arts and Lifestyle Journalism at the University of Arts, London College of Communication.