South Australian Gulf Systems are under increasing stress from recurrent phytoplankton blooms, some of which develop into harmful algal blooms (HABs) with significant impacts on water quality, ecosystem health, and coastal livelihoods. Effective monitoring is therefore critical to support timely mitigation and ecosystem management. However, traditional insitu sampling approaches are constrained by limited spatial and temporal coverage, high operational costs, delayed analysis, and accessibility challenges, reducing their effectiveness in capturing the dynamic nature of HAB events. In contrast, satellite remote sensing offers synoptic, frequent observations that enable early detection and large-scale monitoring of bloom dynamics, supporting improved decision-making for environmental monitoring and management.
To advance satellite-based HAB monitoring in these optically complex waters, CSIRO AquaWatch and SARDI conducted a comprehensive bio-optical field campaign in March 2026. The campaign collected hyperspectral optical measurements, including remote sensing reflectance, absorption and backscattering properties, phytoplankton pigments, dissolved organic carbon, and suspended sediments. Using this dataset, we present the first bio-optical characterisation of SA gulf waters and evaluate the performance of standard satellite algorithms for detecting HABs and mapping water quality. We further discuss pathways for developing regional spectral library–driven remote sensing models to improve HAB and water quality monitoring and management in these SA waters.