Abstract
In addition to potentially generating much desired renewable energy, the future development of offshore wind and wave energy and tidal and riverine hydrokinetic energy is also generating concern regarding possible negative effects of electromagnetic fields (EMF) from generators and transmission cables on aquatic biota. The effects of EMF on the movements of largemouth bass and pallid sturgeon were studied in mesocosm experiments in a freshwater pond. Over a trial period of 4 days, fish experienced alternating 2 h periods in which an underwater energized coil was alternately powered on and off. Electricity moving through the coil created EMF of magnitudes and frequencies expected to be created by underwater electrical transmission cables associated with marine and hydrokinetic energy generating technologies. Surgically implanted acoustic transmitters signaled the locations of individual fish every 1 to 2 min during trials. An array of four receivers was positioned so that the general location of each fish could be determined relative to the position of the EMF source. Paired t-test statistical analysis revealed no consistent significant differences in location or activity relative to the location of the coil for either species as a result of exposure to the EMF. These results suggest that in natural systems where an EMF field can be avoided at a distance of 1 m or more, there should be little effect on the natural movement and activity patterns of these two species. Additional studies with more fine-scale spatial resolution and other species are needed to better understand potential responses in actual field settings.