Rapidly changing ocean soundscapes are disrupting marine animals on a global scale, according to a new study led by Professor Carlos Duarte of King Abdullah University. The experts report that mitigating these impacts is key to achieving a healthier ocean.
“Sound is the sensory cue that travels farthest through the ocean and is used by marine animals, ranging from invertebrates to great whales, to interpret and explore the marine environment and to interact within and among species,” wrote the researchers.
“Ocean soundscapes are rapidly changing because of massive declines in the abundance of sound-producing animals, increases in anthropogenic noise, and altered contributions of geophysical sources, such as sea ice and storms, owing to climate change.”
“As a result, the soundscape of the Anthropocene ocean is fundamentally different from that of preindustrial times, with anthropogenic noise negatively impacting marine life.”
For more than a century, sounds from activities such as fishing, shipping, and development have increasingly contributed to underwater noise pollution. Based on the analysis of more than four decades of published research, the experts found that this noise adversely affects the behavior and physiology of marine animals.
“We find evidence that anthropogenic noise negatively affects marine animals. Strong evidence for such impacts is available for marine mammals, and some studies also find impacts for fishes and invertebrates, marine birds, and reptiles,” wrote the study authors.
‘Noise from vessels, active sonar, synthetic sounds, and acoustic deterrent devices are all found to affect marine animals, as are noise from energy and construction infrastructure and seismic surveys.”
According to the researchers, noise is not the only consequence of human activities, as some areas of the ocean have also become quieter. For example, the hunting of large marine mammals, including highly vocal whales, has led to drastic declines in the abundance of sound-producing animals.
The study authors emphasize that, unlike many other anthropogenic stressors on marine ecosystems, the harmful effects of noise pollution could be addressed and mitigated with new regulations.
“Changing ocean soundscapes have become the neglected ‘elephant in the room’ of global ocean change,” wrote the researchers. “In an era when societies increasingly look to the ‘blue economy’ as a source of resources and wealth, it is essential that ocean soundscapes be responsibly managed to ensure the sustainable use of the ocean.”
“The evidence summarized here encourages national and international policies to become more ambitious in regulating and deploying existing technological solutions to mitigate marine noise and improve the human stewardship of ocean soundscapes to maintain a healthy ocean.”