Coastal marine mammal conservation using thermal imaging-based detection systems

Marine mammal habitats in coastal regions are increasingly threatened as anthropogenic use of these areas increases. Vessel traffic from commercial and pleasure craft leads to increased underwater noise and risk of marine mammal vessel-strike. Mitigation measures advised by competent authorities, such as static and dynamic speed restriction zones or area closures, must be based on reliable data to be justified and find widespread adoption. Thermal detection systems can augment currently employed monitoring approaches such as passive acoustic monitoring or marine mammal observers. Thermal imaging whale detection systems are cost-effective, can be operated around the clock and do not rely on the animal to vocalize, hence have a different availability bias than passive acoustic monitoring. It has been shown in previous studies that thermal detections based on a pronounced blow is possible for larger baleen whales. In this study, we evaluate how effective thermal imaging base whale detection systems are for detecting smaller marine mammals, with a focus on killer whales in Salish Sea.