Electromagnetic fields (EMFs) are a natural part of the Earth’s environment - the Earth’s own geomagnetic field protects from solar winds that would otherwise strip away the ozone layer, leaving the Earth exposed to devastating levels of ultraviolet radiation (Schiermeier 2005). EMFs are created in the marine environment due to the conductivity of seawater as it moves through the geomagnetic field (Tyler & Sanford 1998) and marine life has adapted to the presence of these fields by using them for orientation during navigation and migration (Collin and Whitehead 2004) and some animals are capable of generating their own EMFs for communication, prey detection and predator avoidance (Kullnick 2000). For some animals, like sharks and other elasmobranchs, the ability to detect and use EMFs is well-characterised, but for many, such as invertebrates, our understanding is lacking.
Increasingly, human activities in the worlds’ oceans are responsible for generating EMFs. One of the primary sources of anthropogenic EMFs in the oceans are undersea cables, used for a range of purposes including the transmission of electricity and telecommunications between landmasses. As the world attempts to move away from fossil fuels towards renewable energy sources, undersea cables are becoming more common to transmit energy from where it is generated (e.g., offshore wind farms, solar power plants) to where it is needed. The Basslink and proposed Marinus cables connecting Tasmania to the mainland stand as one of the best examples of this in Australia, providing Victoria access to Tasmania’s overabundance of hydroelectric power.
In recent years, however, anthropogenic inputs into the marine environment have gained recognition as novel sources of pollution capable of harming marine life. Sound was one of the first “new” sources of pollution to be recognised and the development of our understanding of sound in the marine environment presents a useful roadmap that can inform the approach to understanding the impacts of anthropogenic marine EMFs. Early efforts to understand the role of anthropogenic sound in the ocean focused largely on marine mammals due to their “charismatic megafauna” status and their reliance on sound for communication. From there, impacts to finfish fisheries were investigated while invertebrates remained poorly understood. As the potential and importance of impacts to fish and invertebrate fisheries becomes more apparent, the field is becoming more cognizant of the knowledge gaps that persist and impose limits to our ability to draw comprehensive conclusions about the potential impacts and develop mitigation approaches to limit the harm of noise in the environment.
The field of marine EMFs is currently at a similar stage, with the research literature comprised largely of a wide range of animals investigated using a diversity of methods and little ability to form any conclusions. This project will use the lessons learned from research into sound as an emerging source of pollution and apply them towards the field of marine EMFs to synthesise a review of what is known at present, develop a risk assessment specific to Australian fisheries, identify knowledge gaps that limit the progress of our current understanding and offer recommendations aimed at identifying the future research needed to safeguard the sustainability of coastal fisheries against emergent risks like EMF exposure.
Collin S, Whitehead D (2004) The functional roles of passive electroreception in non-electric fishes. Animal Biology 54:1-25.
Kullnick U (2000) Influences of electric and magnetic fields on aquatic ecosystems. ICNIRP: Effects of Electromagnetic Fields on the Living Environment, pp 113-132.
Schiermeier Q (2005) Solar wind hammers the ozone layer. Nature doi:10.1038/news050228-12.
Tyler RH, Sanford TB (1998) Propagation of electromagnetic fields in the coastal ocean with applications to underwater navigation and communication. Radio Science 33:967-987.
