Ocean sounds may help people sleep at night, but marine animals depend on them for survival. Take dolphins, which rely on echolocation to hunt and “clicks” to communicate with their pod. Such species are in trouble, because human-generated ocean noise, or anthrophony, has increased significantly since the Industrial Revolution.
Shipping vessels alone have cranked the low-frequency volume along shipping routes by an estimated 32 times. That’s along with harsh tones from sonar, seismic surveys, pile driving, and even motorboats (all of which can be heard in the video above), which can strand whales and trap narwhals in ice by delaying their migration, according to a review published last week in Science.
The paper notes that climate change also threatens the soundtrack of the sea. The Great Barrier Reef has quieted over the years as it has shrunk in size and become less habitable. Animals that rely on the sounds of coral reefs to locate food and breeding settlements may struggle to adapt.
The authors argue that tamping down the humanmade audio in the ocean should be a core component of environmental policy. And they say it can be done: A study conducted at the start of the COVID-19 pandemic, for example, found that a reduction in shipping traffic coincided with an average decrease of 1.5 decibels in waters along shipping routes near the Port of Vancouver.