IFAW, 2008:

"Commercial shipping, seismic exploration, sonar technology, marine construction, dredging and seabed drilling have collectively raised background ocean noise to potentially threatening levels. Shipping is the biggest single contributor, through its propeller and engine noise.

Between 1965 and 2003 the world’s commercial fleet doubled in size (Fig 1). Ship noise pollution in the Pacific has doubled every decade for the past 40 years.

Cetaceans - whales, dolphins and porpoises - have particularly sensitive hearing and their reliance on sound is almost total. Man-made noise has begun to interfere with and even drown out these crucial sound-based systems (Fig 2). For example, the blue whale once communicated across entire oceans, but noise pollution has reduced  its acoustic range by nine-tenths.

The effects of man-made ocean noise on marine mammals depend on a variety of factors including the nature of  the sound, its frequency, intensity and duration and the type of animal concerned.

There are three main areas of concern about the potential effects of ocean noise pollution on marine animals:

1. That intense noise exposure may cause death or physical injury, even at low levels for some vulnerable species (including temporary or permanent hearing loss), as well as increased stress leading to detrimental consequences for animals’ immune systems and reproductive health.
2. That man-made ocean noise may mask sounds that are vital to marine animals, such as those indicating the existence and location of prey, predators and mates, as well as navigational information.
3. That noise exposure may cause behavioural changes ranging from minor to severe. Noise pollution may interfere with biologically important activities including breeding and calving and with the use of historical migration routes and feeding grounds."

---

Citation and/or URL

Ocean Noise:  Turn it down - A report on ocean noise pollution.  2008. IFAW, United States of America.

Spatial Coverage

Global

Temporal Coverage

1965-2003 

Update Frequency

Not applicable 

Other Information

None