Improving Fish Tracking Over Large Scale Oceans with Autonomous Marine Vehicles and a New Directional Acoustic Telemetry Receiver

The use of autonomous marine vehicles equipped with onboard acoustic telemetry receivers has become increasingly popular for tracking aquatic animals over large scale oceans [1]. In this paper we present the results from at-sea trials of Innovasea's prototype advanced mobile receiver installed on both a Wave Glider and a Slocum glider and deployed in the Gulf of St. Lawrence. In at-sea range testing performed with both glider types, the redesigned receiver improved detection range by an average of 2.5 times that of a conventional receiver deployed in tandem as a baseline and made an average of 6.9 times more detections than the conventional receiver. Furthermore, during the at-sea mission deployment on the Wave Glider, the mobile receiver received 7.2 times more detections than the co-deployed conventional receiver. We demonstrated that the new mobile receiver enabled a significant increase in range relative to previous state-of-the-art acoustic telemetry technology, which ultimately resulted in an increased probability of detecting tagged animals at ocean-scale. The receiver should greatly increase the capability of autonomous vehicles carrying it to detect acoustically tagged animals in the vehicle's operation area.