WP2.Standardisation: Harmonised acoustic metrics and a report describing harmonized test signals suitable for bioacoustics playback studies. Draft International Standard ISO/DIS 17208-3 approved, Final Draft (FDIS) underway. Standardisation of acoustical terminology report widely used internally and externally, selected by ISO/TC 43/SC 3/WG 6 as a working draft ISO 23990 ‘Underwater acoustics – Bioacoustical terminology’. Standardising the characterisation of URN in shallow water has advanced significantly. Underwater noise radiated by a vessel following different testing procedures (standards and classification societies rules) in deep and shallow waters was achieved. Onboard vibrations were measured as well, using the recorded data to evaluate a cost-effective procedure to characterise the noise radiated by a vessel, and the uncertainties related to the different testing methods is quantified. Work on sound particle motion showed that PM can be reliably calculated from sound pressure level.
WP3. Impacts. AquaVib apparatus developed which enabled controlled exposure of marine invertebrates to synthetic URN exposure experiments. The comparative effects of particle motion and acoustic pressure from ship URN on larvae and small species incl. copepods (plankton), bivalves, crustaceans and cephalopods has been evaluated through thier health status as determined by key criteria. Soundscapes have been recorded in three major rivers of Europe. A sound library of acoustic recordings of natural soundscapes of important migratory pathways of fish is available, and comparative analyses of these for diverse river types have been published along with determinations of the impact of shipping noise on receptor spp in terms of how the natural soundscapes are modified by ship sound . The MIGRADROME advanced swim tunnel apparatus has been created and used to determine whether acoustic conditions affect migratory tendencies. Harbour porpoises, harbour seals and pilot whales have been tagged and data analysed to understand how often these are exposed to vessel noise that triggers behavioural changes leading to negative offsets in energy balance, and what the drivers are. The impact of URN on the health of harbour porpoises and seals was measured by assessing hearing loss due to exposure to vessel noise and processing updated information on population demographic rates and health status as input for population modelling. Determination of the relationship between the health status of individual tagged seals and their behavioural response to exposure to URN. URN exposure simulation model showed how URN reductions through slowdowns and technological modifications can lessen impacts on marine mammals. Conclusion that cumulative noise impacts from the global fleet can be reduced immediately by slowdowns and routing vessels away from critical habitats and by technological modifications reduces impact. The health of free-ranging harbour seals was assessed by clinical examination including included blood, microbiological and virological analyses, newly developed molecular biomarkers provided insight into stress and immunological health-related effects in harbour seals. Activity budgets of harbour seals (resting on land or at sea, migrating at sea, foraging), reduced diving and foraging activity and habitat use showed a modest correlation, with health-related measures diverging between individuals as well as their behavioural patterns.
WP4. Solutions. The underlying physical mechanisms of propeller vortex dynamics and associated noise emission have been illucidated through review of the fundamental physical mechanisms underlying propeller vortex dynamics, and a generalized analysis of sound emission mechanisms. A low-fidelity method to predict propeller URN has been defined. Development,validation and verification work about high fidelity methods for hydrodynamic analyses and URN predictions,the design, numerical verification and experimental test of a low noise pumpjet propulsor aimed to replace the actual propeller has been carried out. Propeller optimization framework was extended with empirical relations estimating the RNL of cavitating propellers. A multi-objective design study was carried out for a twin-screw ferry demonstrating the trade-off between propeller efficiency and RNL weighted for the hearing sensitivity of several mammalian hearing groups,while satisfying a range of stringent design constraints acting simultaneously on several operational conditions of the ferry.
WP5. Communications. The SATURN website PowerPoint template, and poster template have created large scale impact. A Sound Terminology Infographic and a Classroom Poster on Ocean Sound have been produced. 8 newsletters released.
WP6. Outreach and Engagement. A policy brief ‘On the Need for Standardized Bioacoustical Terminology’ was developed. Innovative materials for on bioacoustics and underwater noise is being used in schools. The SATURN Stakeholders Group (SSG) includes representatives of key industrial companies, academics, NGOs, port authorities, State agencies and other International Conventions. The Virtual Researchers Environment platform is operational and fully documented. Ocean planner tool implements scenarios from Quonops Online Services to assess the cost-benefit balance planning the use of maritime space under the point of view of shipping route and has been validated with MSP experts to co-create the SATURN Decision Support Tool to include underwater noise considerations into MSP processes. Several actions have highlighted the work of SATURN in IMO, and results are feeding directly into the experience gathering phase for URN reduction measures.
