Mobile Electrocardiogram Monitor for Bottlenose Dolphins in the Marine Environment

The U.S. Navy Marine Mammal Program (NMMP) uses trained dolphins for mine hunting and force protection against unauthorized human swimmers. NMMP has interest in improved cardiac monitoring due to having an aging population of dolphins, several of which over the years have been diagnosed with cardiac disease. In a recent workshop sponsored by the U.S. Office of Naval Research, leading marine mammal researchers gave high priority to the development of improved marine mammal electrocardiogram (ECG) recording. There are currently no user-friendly tags to gather high quality ECG data along with depth and time. Monitoring ECG on dolphins is particularly challenging due to fast and aggressive swimming that causes typical suction cup mounted tags and electrodes to slide, necessitating the use of a neoprene vest secure them in place. However, these vests restrict movement and cause drag and so are not suitable for operational and/or exercising test study conditions. In conjunction with the Joseph M. Long Marine Laboratory (LML) of the University of California Santa Cruz (UCSC), Applied Ocean Sciences proposes the development of a new a state of the art ECG-enabled marine mammal tag with special features to meet and exceed the on-dolphin requirements including: a bi-modal system with a 4-electrode, vest-secured mode for animal diagnostics and a 2-electrode, vest-free mode for operational conditions; flexible (thermoplastic polyurethane) and hydrodynamic tag enclosure; easily configurable data collection settings to balance desired sample rates and battery life; Inertial measure unit (IMU) data to build upon previous ONR research using 2 and 3-axis accelerometers to measure stroke rate and dive patterns; simple, hands free, wireless (Bluetooth) data transfer to a topside application with pairing automatically cued by a surfacing event of sufficient duration. In Phase I, an Alpha prototype version will be developed and in-water tested to show proof of concept. In Phase II, two refined Beta versions will be developed and rigorously tested at the LML lab on two male dolphins following protocols that have already been approved by NAVY BUMED and UCSC animal care and use committees.