Application of autonomous underwater vehicles (AUVs) for monitoring marine biodiversity hotspots

Abstract

Underwater Autonomous Vehicles (AUVs) were only recently developed into functional instruments for examining and biomonitoring seabed features because they provide image acquisition and geophysical sensing. In this research, we aimed to assess the potential of an AUV in mapping benthic habitats and biodiversity in coastal and offshore regions of southeast Tasmania using AUV imagery and high-resolution multibeam bathymetric imaging from the vessel. The AUV monitored different marine habitats and life forms, including highly productive kelp rocky reefs, mid-shelf deep rocky reefs, and sedimentary environments that are otherwise difficult to access. To evaluate the broader-scale spatial distribution of these habitats, the AUV survey data were integrated with more extensive multibeam surveys. Data collected by the AUV markedly improved the understanding of the spatial distribution of benthic habitats and marine life in the study area, which subsequently aids in more informed management and protection decisions. Initial data showed the distribution of an introduced freshwater species, Maoricolpus roseus (New Zealand screw shell), previously documented in the vicinity of rocky reefs but now found in higher densities throughout the southeast shelf. Combining AUV data with broad-scale mapping allowed the measurement of relationships between biological and physical variables, which could be used to construct predictive models for regional biodiversity. The study demonstrates how effective the AUV is as an innovative tool for spatially repeatable surveys. It further highlights the effectiveness of these techniques for monitoring remote regions, particularly for surveying and managing biodiversity within newly established Commonwealth Marine Protected Areas (MPAs). Additionally, this method could be useful for climate change studies, tracking invasive species, monitoring the impact of fishing, and assessing the uniqueness and representativeness of marine ecosystems.