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Underwater Noise Pollution (UNP)



What is UNP?

UNP is intense human-generated noise in the marine environment. It is caused by use of explosives, oceanographic experiments, geophysical research, underwater construction, ship traffic, intense active sonars and air guns used for seismic surveys for oil and related activities.

Why is UNP a Problem?

There is grave concern that proliferation of these noise sources poses a significant threat to marine mammals, fish and other ocean wildlife.

Scientists agree, and a growing body of research confirms, that the intense sound produced by these noise sources can induce a range of adverse effects in marine mammals. These effects include death and serious injury caused by brain hemorrhages or other tissue trauma; strandings and beachings; temporary and permanent hearing loss or impairment; displacement from preferred habitat and disruption of feeding, breeding, nursing, communication, sensing and other behaviors vital to the survival of these species.

High-intensity sound has been shown to have adverse impacts on other marine species as well. Scientific studies have demonstrated that airguns have the potential to injure and significantly reduce catch rates of certain fish species at substantial distances. The proliferation of intense underwater noise poses a threat to already depleted fish stocks throughout the world’s oceans.

As stated most recently by the Cetacean Specialist Group of the IUCN-World Conservation Union: “Military operations involving the use of high-intensity sonar, explosive devices, and other intense noise sources pose both lethal and sub-lethal threats to cetaceans.”

What Can Be Done About UNP?

The obligation to protect the marine environment is embodied in Part XII of the United Nations Convention on the Law of the Sea. Consequently, we believe that in the face of this mounting evidence, the United Nations should endorse a precautionary approach to all sources of intense anthropogenic sound and to explore ways to limit and mitigate their use on the high seas while urging States to adopt similar measures in their territorial waters. The precautionary principle should be applied publicly and transparently to noise generated for military, commercial, and scientific purposes.

In many cases, there are alternatives and realistic mitigation scenarios for reducing and eliminating very loud human-generated noise from the marine environment, including improved passive sonars, using reduced noise energy, mechanical and operational designs that minimize noise, alternative energy sources, etc. Along with the scientific community, we are deeply concerned about the cumulative and synergistic environmental impacts that all of these noise producing systems, operating independently, might have.

Working With The United Nations

A delegation of representatives from several of the organizations working on the Underwater Ocean Noise issue attended the Fifth Informal Consultative Process on the UN Convention on Oceans and the Law of the Sea at the United Nations in New York, June 7-11, 2004. The conference is an annual process to review issues and indicate emerging concerns regarding oceans, and it reports directly to the U.N. General Assembly that meets starting in September. We attended the meeting in order to increase awareness among governments about the need to address UNP and develop international standards regulating noise pollution in the world's oceans. Read the results of this meeting.


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