The State of the Mediterranean Marine and Coastal Environment

Marine Noise

Underwater noise is a growing concern in the Mediterranean due to increasing maritime activity, particularly in the Western Mediterranean. Underwater noise affects the communication and behaviour of marine mammals and certain fishes (UNEP/ MAP 2012; Notarbartolo di Sciara and Birkun 2010). Noise from human activities can drown out the sounds that the animals rely on for communication and orientation, sometimes with serious effects, even death. The responses of cetaceans to human-created noise fall into three categories: • Behavioural: changes in surfacing, diving, and heading pat- terns; abandonment of habitat. • Acoustic: changes in type or timing of vocalisations; masking acoustic signal over large areas. • Physiological: temporary and permanent hearing loss; mor- tality (Notarbartolo di Sciara and Birkun 2010; Abdulla and Linden 2008). Beaked whales appear to be particularly vulnerable to noise (Notarbartolo di Sciara and Birkun 2010). Incidences of mass stranding and mortality of Cuvier’s beaked whales have been reported in relation to the use of military sonar in the Medi- terranean (Nortarbartolo di Sciara and Birkun 2010). Seismic sonar (used in the oil and gas industry), the second major

Marine noise is human-generated sound from such activities as high-intensity sonar and seismic surveys and from the background sounds of commercial shipping and wind farms.

source of potential noise impacts on Mediterranean marine mammals, has received less attention. There is growing evi- dence that fish may also be negatively affected by noise. Pos- sible impacts include impaired communication, stress, habi- tat abandonment, hearing loss, and damage to eggs (Abdulla and Linden 2008). The impact of military sonar on marine mammals has influenced regional marine policy in the Mediterranean in recent years, but this has not yet been translated into mitigation at a broader scale (Dolman et al. 2011). In 2007, the Contracting Parties to the Agreement on the Conservation of Cetaceans in the Black Sea, Mediterranean Sea and Contiguous Atlantic Area (ACCOBAMS) adopted Guidelines to address the impact of anthropogenic noise on marine mammals in the ACCOBAMS area . A recent ACCOBAMS status report, however, found that no significant progress has been made to address the problem of marine noise, nor have there been any systematic attempts to coordinate industrial ac- tivities with marine mammal conservation initiatives (Notarbar- tolo di Sciara and Birkun 2010).

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HUMAN PRESSURE, STATE AND IMPACTS ON MEDITERRANEAN ECOSYSTEMS