Whales communicate with each other across huge distances. They and many other marine animals also rely on a fine-tuned sonar system for orientation. Dolphins have a great built-in echolocation sense – which is well described by the Dolphin Institute. Marine mammals use their smart auditory and sound systems to communicate with each other, to locate and catch their prey – and to find their mates. What happens when all these life-essential actions are hindered? How often and how severe does it happen in our days already?
How do you measure sound pollution? By numbers of stranded dolphins and whales each years, at various coasts? It appears evident that what we perceive as land noise has a much stronger effect on marine life. Quoting Ocean link: “A ten decibel increase in sound represents a ten times increase in volume while a 20 decibel increase represents a 100 times increase in volume; a thirty decibel increase in sound represents a 1000 times increase in volume. Sound also travels faster and further in water than in air. High intensity sound in the oceans may not dissipate for thousands of miles. Humpback whales… are particularly sensitive to oceanic noise pollution.”
For anyone interested, the Monterey Insitute has an excellent animation about noise pollution and whale behaviour. It simulates a migrating whale group moving along a coast. By adding factors like propellor noise, ship traffic and others, the user can directly observe – and get explained – what the effects of such acoustic disturbances are.
While is appears clear that the major problems with noise pollution stem mainly from bigger ship traffic, the following is worth to keep in mind also for constructors and owners of smaller boats: “In terms of ship design, isolating engines from hulls would help reduce noise output. There also has to be regular acoustic maintenance of ships such as cleaning the propeller of debris (this reduces noise considerably), general maintenance such as repairing bearings, loose plates and so forth.”
- Cruising in marine sanctuaries - May 16, 2016
- Sailors for ocean science - April 14, 2016
- Marine noise hotspots in the Mediterranean: First scientific basin-wide map - March 6, 2016
- Why Yachtrecycling? 11 good reasons - March 6, 2016
- Global directory of sustainable nautical products and services - August 15, 2015