Bureau of Ocean Energy Management: Impacts of EMF on Marine Life

Ms. Donna M. Schroeder from the Bureau of Ocean Energy Management (BOEM), presented findings of the study for potential impacts of electro magnetic fields on marine life at the Marine Renewable Energy Center Technical Conference. There is the recognition that there are marine species that rely on magnetosense or electric field receptors for life functions. How changes in these electric and magnetic fields affect these functions is not fully understood.

The study’s objectives were to understand the sensitivities of marine species to electric and magnetic fields produced by undersea transmission cables. Studies took into consideration types of fields such as electric, magnetic and induced electric. Geomagnetic field influences were also taken into consideration with local variations, the general increase in latitude, and orientation relative to DC cable to determine interaction with the geomagnetic field. The study used modeling that included computer algorithms and inputs (voltage, current flow, line phasing, and conductor configurations). Other considerations included power cable configurations, and cable designs.

It was found that magnetosensitive species such as sea turtles, some marine mammals, and some decapod crustaceans (lobsters, crab, prawns, shrimp) were more likely to be able to detect electro magnetic fields from DC cables than from AC cables. Electrosense is well documented with sharks and rays. Species at higher risk would be those closer in the water column to the seabed as opposed to pelagic species.

BOEM will be moving forward in 2012 on the Monterey Accelerated Research System (MARS), in the Monterey Bay National Marine Sanctuary, a renewable energy in situ power cable observation study.