Addressing underwater noise in Europe: Current state of knowledge and future priorities.

Abstract

Anthropogenic underwater noise impacts have become a hot topic for environmental managers and regulators in Europe and beyond. Sounds from human activity at sea include shipping and other marine craft, construction and installations, sonar and seismic surveys. This Future Science Brief presents an update on the previous EMB publication on underwater noise, Position Paper N° 13 on “The effects of anthropogenic sound on marine mammals: A draft research strategy". This Future Science Brief expands the scope of the discussion beyond marine mammals to fishes and invertebrates, and outlines key developments that have taken place since the Position Paper’s publication. The main chapters of the document focus on: the advances in our knowledge on anthropogenic underwater sound in the Ocean; the new knowledge that has been developed on the effects of noise on marine organisms; and the measures that have been taken to address the issue of underwater noise. While significant progress has been made, knowledge gaps still remain. The document therefore presents these outstanding issues and highlights priority actions for addressing them. This Future Science Brief states that the most urgent priority actions/questions are to: 1. Develop collaborative international standards applicable to all steps of the risk framework; 2. Conduct comprehensive monitoring combined with spatial ecological modelling of marine species’ dynamic habitat use, movements, behaviour and distribution to establish baselines; 3. Foster comprehensive monitoring and data collection of current soundscapes / ambient noise, including via joint monitoring programmes in existing and new areas; 4. Shortlist high priority (and biologically relevant) sound sources and perform standardized source characterization studies; 5. Undertake hearing studies on baleen whales and on selected fish and invertebrate species; 6. Conduct field and modelling studies on changes in acoustic habitats to identify masking risks to communication in fishes and marine mammals; 7. Conduct further studies on behavioural response of marine mammals and fishes due to exposure to high intensity impulsive sounds to assess population consequences; 8. Conduct taxa-relevant studies on hearing impairment and physiological stress to address existing knowledge gaps in invertebrates, fishes and marine mammals; 9. Conduct dedicated studies including multi-species investigations, predator-prey interactions, and interaction with other food web levels, addressing the question of how noise impacts combine with other stressors; 10. Develop frameworks and conduct studies to allow population-level assessment of effects from cumulative impact of noise and other pressures; 11. Conduct dedicated modelling and field studies to improve understanding on effectiveness, safety and cost-effectiveness of noise mitigation devices, mitigation measures and management options; 12. Develop regional action plans and guidelines for Environmental Impact Assessment and policies; and 13. Initiate international collaborative transdisciplinary projects to develop stakeholder and societal capacity in understanding and addressing underwater noise.