ANSWER 1

Freshwater inputs are an important and natural part of the Torres Strait environment. Torres Strait Islanders have observed that periods of unusually high freshwater input can affect marine ecosystems, sometimes contributing to fish and coral mortality. These freshwater events are often associated with heavy rainfall and river discharge from Papua New Guinea, particularly the Fly River, as well as broader regional climate conditions. Seasonal winds and currents can impact the location and persistence of these freshwater intrusions.

Two recent papers have explored how freshwater inputs in the Torres Strait can impact the entire marine ecosystem. Freshwater can lower salinity, increase sediment and turbidity, and reduce light reaching coral reefs and seagrass habitats. These changes can have flow-on effects throughout the food web, including on species that support fisheries, food security, cultural practices, and local livelihoods (Plaganyi et al., 2025; Blamey et al., 2026). There are also studies that have looked at water quality and pollution threats from the Fly River runoff by Waterhouse et al. (2021) and summaries of this work can be found here: https://nesptropical.edu.au/index.php/round-5-projects/project-5-14/

Freshwater inputs can be monitored using a combination of ocean observing stations, satellite imagery, water quality measurements, and community observations. Predicting future freshwater events is becoming increasingly possible through advances in ocean and climate modelling. As part of a Torres Strait Regional Authority (TSRA) funded project modelling the impacts of climate change on fisheries in the Torres Strait, the CSIRO is currently developing a high-resolution hydrodynamic model of the Torres Strait region that can be used to explore the source, extent, and movements of freshwater patterns. Combining modelling and scientific monitoring with the observations and knowledge of Torres Strait Islander communities offers the best opportunity to improve early warning systems and support adaptation to future climate impacts. Project updates and other climate change information relevant to Torres Strait can be found here:https://doi.org/10.25919/z0ga-5891

References:
Plagányi et al 2026: https://www.science.org/doi/full/10.1126/science.adv0367
Blamey et al., 2026: https://www.sciencedirect.com/science/article/pii/S007966112600131X
Waterhouse et al., 2021: https://nesptropical.edu.au/index.php/round-5-projects/project-5-14/