Magnetic fields generated by submarine power cables have a negligible effect on the swimming behavior of Atlantic lumpfish

Abstract

Overview

Submarine power cables are essential for transmitting electricity across vast distances, especially for offshore wind facilities. These cables emit magnetic fields (MF) due to the electrical currents passing through them, potentially impacting marine life, particularly magnetosensitive species.

Study Focus

The study examines the Atlantic lumpfish (Cyclopterus lumpus), a migratory fish in the North Atlantic Ocean and Barents Sea. The research aimed to determine if the lumpfish shows behavioral changes in response to magnetic fields equivalent to those found near high voltage direct current (HVDC) submarine cables.

Methodology

• Laboratory experiments with juvenile lumpfish exposed to artificial MFs of 230 µT - simulating the field near a submarine cable.
• Observations of swimming behavior for 30 minutes with varying magnetic field conditions.

Findings

Despite being able to sense the magnetic fields, as indicated by a 16% reduction in swimming speed when exposed, juvenile lumpfish did not exhibit significant changes in overall activity patterns or migration tendencies. This suggests that the EMFs generated by submarine cables likely have minimal impact on their migration and homing behaviors.

Conclusion

While juvenile lumpfish can detect changes in magnetic conditions, the minor reduction in swimming speed near submarine power cables is unlikely to have substantial ecological effects. It is essential to monitor and mitigate any potential environmental impacts as the prevalence of submarine cables grows.