Commercial and passenger maritime traffic, oil, gas and mineral exploration, coastal and offshore constructions, naval and sonar exercises are some of the growing anthropogenic underwater noise-producing activities in the Mediterranean Sea.
This map shows the intensity and distribution of maritime traffic routes in the Mediterranean Sea (data from MarineTraffic - Global Ship Tracking Intelligence; www.marinetraffic.com - used by E. Di Franco et al., 2020, in their review of the effects of marine noise pollution on Mediterranean fishes and invertebrates). The red regions are under acute marine traffic which also cause noise pollution by large vessels. This map does not show the many other marine activities with smaller vessels and marine leisure vehicles that also produce noise, such as power boats and jet skis. Additionally, the type of noise produced by naval and sonar exercises and developments involving drilling and piling on the seabed to support structures are even more aggressive in their noise pollution.
Scientific studies have increasingly reported impacts of noise pollution from anthropogenic activities on marine biodiversity, fish, turtles and marine mammals with consequent physical, physiological and behavioural alterations which have led to risks to their habitat use, reproduction and survival. For example, it has been demonstrated that naval exercises involving the use of mid-frequency active sonars caused several mass stranding events of Cuvier's beaked whales along the coasts of the Mediterranean Sea, including Maltese coasts. Therefore, noise pollution may seriously affect the health and services provided by marine ecosystems and biodiversity.
Sound travels much more efficiently in the aquatic marine environment than in air therefore impacting far larger 3-dimensional marine space from respective sources. Unfortunately, as underwater marine sounds are not perceived by humans with their ears out of the water, noise pollution has often been slow to act upon at policy, monitoring and implementation in many Mediterranean countries. Yet noise may be devastating to many marine species, very much like when someone is trying to talk to another person or do anything with a loud background noise close by, not to mention the stress and health hazards when suffering prolonged periods of noise through the day and night.
The Marine Directive 2008/56/CE, specifically the Marine Strategy Framework Directive, was set as an important way forward to preserve the marine environment as it aimed to achieve Good Environmental Status (GES) at regional level. It therefore also highlights the need to establish anthropogenic noise levels that do not affect marine biota (Descriptor 11). These levels need to be measured according to the established standards many of which are entranced in the same directive.
In Maltese water the first ever acoustic monitoring and assessment, with hydrophones, along these lines started off with the quietMED project some years back, after receiving funding from the DG Environment - European Commission, to device better coordination among member states that share marine regions and sub-regions to increase the protection level and the conservation status of Mediterranean marine spaces against the damages caused by anthropogenic underwater noise. Through this Mediterranean acoustic project, monitoring marine sounds in different areas, it was possible to investigate ways to improve the level of coherence and the comparability in measures of the MSFD's Descriptor 11. Investigations involved considerations for best underwater noise monitoring implementation in the Mediterranean Sea Region.
In this regard Maltese Ministries for the Environment and Transport gave their logistic support for the Maltese marine underwater noise monitoring undertaken by the University of Malta (UM) through the participation of the Conservation Biology Research Group from the Department of Biology, Faculty of Science, joining forces with other European scientific research experts. This active involvement has achieved the first ever dedicated acoustic monitoring and MSFD targeted measures of noise levels in Maltese waters. The research also contributed to Mediterranean-wide efforts to achieve coherent, coordinated and consistent updates of the determinations for Good Environmental Status and environmental targets for this region.
Through the years, the Conservation Biology Research Group (CBRG-UM), has continued to spearhead this important field of marine research which also allowed for the associated investigations of sounds produced by marine species around the Maltese Islands, including those by dolphins and whales. Such technological innovations in field research complements the long-term visual field research undertaken through marine and aerial surveys also led by Prof Adriana Vella (CBRG-UM) since 1997. Here again we see the integration of various tools, expertise and investigative methods to obtain a more holistic picture of the marine environment and its biodiversity. The many applications of these scientific advancements promise fruitful outputs toward carefully addressing various environmental and governance needs for sustainable progress.
The University of Malta Maritime Platform (UMP) represents a wide diversity of experts that lead useful research and academic training in areas that are of paramount importance as the planet's seas and oceans increasingly suffer from rapid change and anthropogenic activities. The latter should no longer proceed unchecked when technology provides effective means to prevent this and therefore also aiding laws and directives to be implemented efficiently.
Such interesting research and applications will also be presented at the University Maritime Platform Conference - Innovation in Marine and Maritime Sustainable Developments: Research and Applications - running through from 7 to 9 May, showcasing how state of the art innovations in acoustic monitoring may aid timely mitigation and implementation of sustainable marine developments, activities and conservation management.
This conference will uniquely integrate diverse presentations allowing dialogue across different fields including technology, maritime, environment and governance.
Registrations to this conference are open for participants interested to learn and share experiences while contributing to recommendations that this conference will prepare for national and European consideration.
Conference website: https://www.um.edu.mt/events/umpc2025/
For further information on the UMP and CBRG-UM contact Prof Adriana Vella: [email protected]
