Noise from shipping operations and other human activities can be disruptive to marine animals, especially species like whales which rely on calls through the water to communicate. The good news is there are a few simple solutions that would greatly reduce these auditory disruptions under the sea.
Researchers analyzed 500 studies of marine noise pollution to find instances where noise could be significantly reduced with simple strategies. First things first, creating quieter propellers and rerouting shipping vessels away from sensitive habitats could be very impactful. About 85 percent of shipping noise comes from propellers, specifically from a condition called cavitation, a propeller design issue. Fortunately, these propellers can be retrofitted to improve efficiency and reduce noise by 75 percent.
Another potential area for improvement is seismic surveying. This is primarily conducted for oil and gas exploration, but traditional ocean seismic surveying uses frequent pulses which create auditory disruptions for marine life. Fortunately, ExxonMobil, Shell, and French energy company Total designed a marine version of seismic surveying technology which lowers overall sound pressure levels. These are expected to go into circulation in 2023 and widespread adoption in conjunction with reduced oil and gas exploration in favor of renewable energy sources could greatly benefit marine ecosystems.
Offshore wind farms are another prime location for noise reduction. Easily installed acoustic bubble curtains reduce noise by 95 percent to create renewable energy that can also be generated in harmony with marine life. Ultimately, the most appropriate noise reduction strategy depends on the area and marine life that lives there, but the availability of these solutions means the technology already exists, all that is left to do is implement it.