Effect of electromagnetic fields from renewable energy subsea power cables on righting reflex and physiological response of coastal invertebrates

Offshore renewables are expanding, yet more information is required to understand their possible impacts on the environment. Little is known about the effects of Electromagnetic Fields (EMF) from subsea power cables on marine life. This study simulated an EMF of 500 μT, as modelled for an export cable over a rocky shore, where the industry standard cable burial would not be possible. Righting reflex, refractive index of haemolymph/coelomic fluid, and total haemocyte/coelomocyte counts were measured for four coastal invertebrates (Asterias rubens, Echinus esculentus, Necora puber, and Littorina littorea). No significant differences were found in either behavioural or physiological responses. This was the first study to investigate EMF exposure on righting reflex, and the first ever EMF study on edible sea urchins and periwinkles, and only one of a couple for common starfish and velvet crabs. It therefore, provides valuable data for environmental impact assessments, marine spatial planning, and commercial fisheries. [Display omitted] •First Electromagnetic Field (EMF) study on Littorina littorea and Echinus esculentus•EMF also tested on Asterias rubens and commercially important Necora puber.•EMF on righting reflex studied for first time, which was not significantly affected•Refractive index of haemolymph/coelomic fluid not significantly affected by EMF•Total haemocyte/coelomocyte cell counts not significantly affected by EMF