Autonomous Multichannel Acoustic Recorders on the VENUS Ocean Observatory

The Autonomous Multichannel Acoustic Recorder (AMAR, JASCO Applied Sciences) is a sophisticated precision instrument for passive acoustic monitoring and accurate underwater sound level measurements. It can be integrated with small hydrophone arrays and non-acoustic oceanographic sensors. To date, AMARs have typically been used autonomously and deployed for a few months to a year on oceanographic moorings; however, AMARs are also capable of real-time data streaming when connected to a data telemetry system. This paper describes the capabilities and functionality of the AMAR through the example of its integration within Ocean Networks Canada´s VENUS Ocean Observatory deployed off the coast of British Columbia, Canada. The recent deployment of two AMAR-based hydrophone arrays and associated non-acoustic and oceanographic sensors within the VENUS system is presented in detail. The planned research and development within the AMARs on VENUS program, as well as preliminary results on the real-time automatic detection, classification, localization, and tracking of marine mammals, are presented. The two AMARs deployed on the VENUS Ocean Observatory demonstrate that, unlike traditional underwater acoustic recorders, the AMAR can act as a hub for mini ocean observatories, capturing and transmitting both acoustic and non-acoustic sensor data in realtime. It is demonstrated that the AMAR is an effective technology that can be used in near-shore, small-scale, low-cost ocean observatories.