SWIM - Main measurement campaign

The seas and oceans provide resources for a range of industrial and recreational activities, from commercial shipping to recreational boating, and from resource exploration to wind energy. All these rapidly expanding activities generate sounds, often very loud, that travel long distances through water. The growth of the ocean economy means that human-generated noise is becoming dominant in marine soundscapes worldwide. It has been observed that this can be very harmful to marine life, but the extent of the damage has not been quantified. Scientific knowledge of underwater noise pollution is growing rapidly but remains limited; further research is needed to provide policymakers with essential guidelines for the sustainable exploitation of marine resources. Future noise pollution models will need to include precise information on specific noise sources, the propagation of elastic waves in marine environments, and the impact of noise on individual marine species. SWIM helps us understand how new wind farms could affect toothed whales, depending on their characteristics (such as fixed or floating turbines) and their location.

The main survey took place in the summer of 2025. As with the preparatory campaign, this survey lasted three days, and recordings began from the same locations as the preliminary survey. The acquisition system used during the main campaign differed from that employed in the preliminary phase, as the power supply chain had been redesigned. At the same time, in the main survey was introduced the use of a portable CTD system to identify possible gradients in sea temperature and salinity that could affect the sound velocity in the water column.