Multi-channel acoustic data acquisition and telemetry on an autonomous vehicle for marine mammal monitoring

The impact of anthropogenic noise on marine mammals is becoming an increasingly important area of study for regulatory and research purposes. To assess these impacts, archival underwater acoustic recorders are typically deployed before the activity of interest, then retrieved and their data analyzed afterwards. The significant drawback to this approach is that impacts can only be assessed well after the activity in question, making mitigation of that particular activity impossible. A more recent technology developed to reduce the probability of whale-ship collisions, the Auto-Buoy system [1], reduces the time between activity and mitigation with a delay of 20-30 minutes, but does not address noise impacts. Recent interest in using the Wave Glider^® (Liquid Robotics, Sunnyvale, CA) for environmental monitoring related to the oil and gas industry [2], and using it to acquire acoustic data [3-5], suggests the potential for using this autonomous vehicle as a real-time monitoring and mitigation tool. The current work involves developing an acoustic data acquisition and transmission system for use with a Wave Glider, to provide real-time data for marine mammal monitoring and mitigation [6]. The goal of the system is to be capable of persistent, autonomous, real-time monitoring of marine mammals in areas that would otherwise not be surveyed, as it will not require a local ship for its deployment, its retrieval, or reception of data for human review.