Abstract
A program of experimental field surveys is underway off the coast of South Florida, USA to characterize the electromagnetic field (EMF) emissions in the water column from submarine cables, and monitoring for responses of local aquatic species is described. The field surveys are being conducted at the South Florida Ocean Measurement Facility (SFOMF), which is a cabled offshore in-water navy range. The program is in support of assessing the impact of EMF emissions from offshore ocean energy conversion (OEC) devices. Several laboratory studies show that diverse aquatic species, including sharks and rays, are electrosensitive, while others can get disoriented by magnetic anomalies. However, field data to validate potential relationships between observed responses and the EMF emissions in situ are lacking, in support of developing accurate verified models to evaluate the potential responses of marine species and impact (if any) of EMF emissions on ecological communities. In the present study, background EMF levels and EMF emissions due to submarine cables are measured using a custom E-field sensor and a commercial magnetometer deployed from an autonomous underwater vehicle (AUV). The potential responses of local marine species are observed using divers on SCUBA, complemented with fixed cameras on the sea bottom and by a set of video cameras mounted on the AUV. The objectives are: 1) to characterize the EMF emission levels associated with submarine cables 2) to monitor potential responses of aquatic animals to the emissions and 3) to develop an associated database of field observations. As control, observations of EMF levels and in situ marine species are conducted with power in the cables turned off. The procedures involved in the study and initial results from the surveys and analyses conducted to date are described.