ITSASDRONE, an autonomous marine surface drone for fish monitoring around wave energy devices

Abstract

One of the primary foundations of the EU Blue Growth policy is the development of ocean energy. While the technological development of devices is advancing quickly, little is known about their possible environmental implications. The SafeWAVE initiative aims to increase understanding of potential environmental effects from wave energy projects in the coastal waters of Portugal, Spain, and France. The aim of this work was to monitor the interaction between the WEC and the fish community in the Spanish study area (BiMEP). However, the device to be monitored had to be replaced by a floating laboratory (HarshLab) in the same area, since the WEC suffered a series of unforeseen events that made its use impossible. The monitoring was carried out using an autonomous vehicle (ITSASDRONE) equipped with a scientific echosounder, which recorded acoustic data that provided information on the abundance of fish in the area. Schools of unidentified small pelagic fish were observed distributed throughout the water column, predominantly near the bottom in the area of the device. The acoustic sensors showed a relatively high abundance in the BiMEP area, generally equal to or higher than in the access route from Armintza harbor. However, these results are preliminary and should be considered as baseline information. Future studies are needed to further investigate the relationship between WECs and fish aggregation.