This project will use sensors attached directly to longline fishing gear to improve understanding of the biophysical drivers of catchability for commercially valuable tuna and billfish. These sensors, part of the IMOS FishSOOP program, provide fine-scale temperature-at-depth data across broad spatial extents. Given that tuna and billfish are highly migratory and deep-diving, improved rendering of subsurface temperature dynamics may greatly improve models of catchability. A data-assimilative regional oceanographic model configuration (EAC-ROMS) which assimilates FishSOOP data will be compared with another oceanographic model (BRAN), quantifying the impact of novel data sources on fisheries catch models. These results will be used to build ecological data products to increase forecasting capacity, informing proactive decision-making for industry and management. This project is in collaboration with industry through Tuna Australia, and aims to build relationships with stakeholders, management authorities, and fisheries researchers.