Applications of active-acoustic and complementary technologies in marine ecosystem science

Abstract Since the invention of echosounders and sonars in the early twentieth century, the applications of active-acoustic instruments have expanded from single-frequency range detection and fisheries stock estimates to wider explorations of ecosystem dynamics using increasingly advanced tools. Echosounders are now integrated with ships, nets, probes, uncrewed and autonomous vehicles, moorings, landers, and marine mammals, to sample the oceans on ecologically relevant spatial and temporal scales. Yet the uptake of these technologies by ecologists is hindered by steep learning curves, data post-processing techniques and availability, and funding challenges, as well as persistent knowledge gaps within the field of acoustics. An interdisciplinary approach, joining expertise in sampling technology and ecology, coalesces the people, ideas, resources, and data needed to conduct priority science. Here, we present the current and anticipated applications of active-acoustic and complementary instruments deployed on a variety of platforms to conduct interdisciplinary marine ecosystem science—beyond estimates of fisheries stock biomass. We also discuss the skill development, resource and data access, and interdisciplinary collaboration necessary to address challenges to marine ecosystems and progress the priorities identified in the ICES Science Plan.