On the seabed of the North Sea, beneath spinning turbines harvesting wind for European power grids, a hidden drama unfolds in the bodies of sharks and rays—creatures wired to detect the faintest electromagnetic whisper. A six-year study from Wageningen University & Research has found that the high-voltage subsea cables of offshore wind farms produce electromagnetic fields strong enough to alter the behavior and development of these sensory-rich animals, raising urgent questions about the hidden costs of renewable energy expansion.
Sharks and rays possess specialized electroreceptors called ampullae of Lorenzini—jelly-filled sensory canals around their heads and snouts that can detect extraordinarily weak electromagnetic fields from prey, predators, and Earth's geomagnetic field itself. These animals depend on this sensory system for hunting, navigation, and long-distance movement, particularly in murky waters where visibility is poor. As offshore wind farms expand rapidly across the globe's renewable energy transition, Wageningen researchers recognized that these creatures would be unavoidably exposed to the EMFs radiating from submarine power cables—and wanted to understand what that exposure might mean.
The Elasmopower project, led by Ph.D. candidate Annemiek Hermans, combined long-term field measurements with laboratory experiments on two European species: the small-spotted catshark and the thornback ray. Researchers exposed embryos, juveniles, and adults to electromagnetic field levels similar to those near operational cables, testing whether developmental stage and species influenced sensitivity. The findings, presented by scientist Erwin Winter at the Sharks International 2026 conference in Colombo, Sri Lanka, in May, revealed a troubling pattern: responses varied significantly by species and life stage, with some groups far more vulnerable than others.
The most concerning discovery involved early development. Many sharks and rays lay eggs in tough protective cases—colloquially called "mermaid's purses"—attached to the seabed. Inside these cases, embryos typically respond to environmental cues, including the electromagnetic signatures of nearby predators, by freezing in place to avoid detection. But thornback ray embryos exposed to EMF levels similar to those from cables became significantly more active during development instead of remaining still. While researchers observed no differences in hatching success, growth, or development time under experimental conditions, the behavioral shift raises a sobering question: in the real ocean, would this increased movement make vulnerable embryos more visible to predators? The research suggests it could increase predation risk during the critical early stages of life.
Yet the picture is more complex than simple harm. Environmental DNA surveys inside offshore wind farms detected multiple shark and ray species living within these industrial zones, suggesting the farms may paradoxically provide refuge areas where these animals can shelter and feed. The mechanisms behind this benefit remain unclear, and major knowledge gaps persist about long-term ecosystem effects.
As renewable energy becomes essential to combating climate change, Wageningen's work demonstrates that the transition to clean power is not neutral for ocean life. The research hints at a broader concern: other bottom-dwelling marine organisms, such as flatfish, may experience similar sensory disruptions from subsea cables. The path forward requires not abandoning offshore wind, but understanding and mitigating its ecological ripples—ensuring that our race toward renewable energy doesn't unknowingly alter the sensory world of creatures already facing mounting ocean pressures.