Did you know that our oceans are alive with sound? The world below is a vibrant sonic atmosphere and home to thousands of species who communicate through the medium of water. Scientists are beginning to understand the importance of the sounds of our oceans not only to the life forms within them but also to sustaining a healthy ocean and overall planet at large.
“Sound travels five times faster in the water. The ocean is a giant conductor of sound, an aquatic internet for every organism in it. They feel it in their bodies, and as they create sound, they are physically reaching out” (Under the skin of the ocean, there’s a super-loud fishcotheque going on, Philip Hoare, The Guardian)
According to Stephen Simpson, a marine biologist at the University of Bristol in England, a healthy ocean is noisy. “Fish whistle and grunt, sea urchins scrape food from the seabed, dolphins squeal, and spiny lobsters play their antennae like violins. Animals like all this noise. Like the bustle of a big city, the familiar din of a healthy habitat attracts young creatures that are seeking a permanent home”. (Playing Recordings of a Healthy Ocean Can Help Restore Marine Ecosystems, Elizabeth Preston, Smithsonian Magazine)
Over time, our oceans have taken a hit. According to National Geographic, human activities are threatening the health of our oceans, as over 80% of marine pollution comes from land-based activities. One of the biggest threats is plastic pollution, and other factors include the effects of climate change and global warming. According to an article from The Hill covering a report released by the National Oceanic and Atmospheric Administration (NOAA) and partners, including the Global Coral Reef Monitoring Network (GCRMN), 14 percent of the world’s coral reefs were lost between 2009 and 2018. Coral reefs play an essential role in the health of our oceans as they “protect coastlines from storms and erosion, provide jobs for local communities, and offer opportunities for recreation. They are also are a source of food and new medicines. Over half a billion people depend on reefs for food, income, and protection. These ecosystems are culturally important to indigenous people around the world”.
Credit: Ocean Conservancy
Scientists are now turning to sound to assist in the rehabilitation of our oceans. According to an article in Smithsonian Magazine, in 2017, marine biologist Stephen Simpson and a team of scientists used coral rubble to build dozens of new miniature reefs. They then placed speakers nearby to play recordings made when the reefs were healthy and found that twice as many young fish settled on the reefs near those speakers. This project is one of many research efforts demonstrating how sound may be a critical tool for healing our oceans and ensuring a healthy future.
According to Simpson and other researchers, sound attracts animals. “The acoustic world underwater is critical for the survival of most animals,” says Simpson. An example of this is how sound cues baby fish to find and settle on coral reefs after their first weeks of swimming in the open ocean. With this growing understanding, scientists are experimenting ways in which field recordings can be used on land and underwater to help restore habitats that have suffered.
In the case of our oceans, a growing understanding of ocean acoustics - the study of sound and its behavior in the sea - has become an important way for scientists to support the health of our oceans. Listening to underwater sounds has an essential role in alerting scientists to Earth events and the overall status of the planet.
Hydroacoustic monitoring (listening to underwater sounds) has allowed scientists to measure global warming, listen to earthquakes and the movement of magma through the sea floor during major volcanic eruptions, and to record low-frequency calls of large whales the world over. As our oceans become more noisy each year, the field of ocean acoustics will grow and only become more essential. (Understanding Ocean Acoustics, Sharon Nieukirk, Research Assistant Acoustic Monitoring Project NOAA Pacific Marine Environmental Laboratory)
All in all, the health of our oceans plays an important role in maintaining a healthy planet. Our planet is composed of 71% water, and our oceans make up about 95% of that water. Healthy oceans make for a healthy planet.
A healthy ocean is a prerequisite for a healthy planet and healthy human communities. Eighty per cent of all life on Earth is found in the ocean. It is the world’s biggest biosphere and home to great biological and carbon pumps and food webs that control our climate and sustain us all. (United Nations)
Friday, April 22, 2022, is Earth Day - an annual day dedicated to demonstrating support for environmental protection. This year’s theme, #InvestInOurPlanet, is bringing awareness to how we can all invest in a greener (or, in this case, bluer) future for all.
Learn more about the ways in which we can invest in our planet in our article, Preserving The Sounds of The Earth, written by Andrea Lamount of Sound Earth Legacy - a non-profit organization aiming to preserve the sounds of the Earth and supporting pioneer scientific environmental projects through sound and music.