Résumé
The Southwest Indian Ocean (SWIO) has one of the highest levels of marine diversity and endemism in the world, with millions of people in coastal areas reliant on marine ecosystems for both their livelihoods and well-being. As such, ensuring the long-term sustainability of these ecosystems will rely on relevant data applicable to management, including movement and connectivity information both within and between countries. Understanding connectivity between different coastal habitats and between countries is critical for effective fisheries management, particularly if national or regional conservation policies are misaligned when it comes to resource use. This review synthesizes acoustic telemetry research to guide future work in the region. The vast majority of acoustic telemetry work in the SWIO region, conducted as early as 2003, has been in South Africa, given the established national Acoustic Tracking Array Platform that was formalised in October 2011. This platform, which currently comprises approximately 300 acoustic receivers and monitors the movements of 38 species (almost 55 species tagged in total), has already collected more than 25 million individual data points. However, acoustic telemetry research is growing in other countries in the region, including Seychelles, La Réunion and southern Mozambique. Many of the first movement studies in the region involved small, isolated receiver arrays with limited capability to record large-scale movements, with researchers rather pivoting to satellite telemetry. However, over the past decade, the interest in acoustic telemetry for studying movement has increased, with more receivers being deployed throughout the SWIO collecting data on large-scale movements. This includes studies highlighting persistent transboundary movements of important fishery species between South Africa and Mozambique, and bull and tiger sharks moving from La Réunion as far west as South Africa, Mozambique and the Malagasy west coast. With growing interest in acoustic telemetry in the SWIO region, this review will serve as a valuable resource when scoping and planning future research projects in the region.