Background/Aims
Northern Australian tropical marine fisheries and ecosystems are impacted by climate change in a fundamentally different way to sub-tropical and temperate systems, particularly for species that are trapped by geo-physical barriers with few or no latitudinal climate-refugia. Nor is rising sea surface temperature the dominant driver of system change, such that there is a need to better understand complex and compound climate change drivers in order to plan proactive adaptation solutions.
Methods
We use a range of climate-linked stock assessment models and MICE (Models of Intermediate Complexity for Ecosystem assessments) fitted to available data from tropical northern Australian ecosystems, including the Gulf of Carpentaria, Joseph Bonaparte Gulf and Torres Strait. We investigate how species (including sawfish), fisheries (including prawns, lobsters) and habitats (such as seagrass and mangroves) are influenced by compounding impacts from cyclones, warming shallow seas, sea-level variability, and freshwater influx.
Results
We share our latest research showing how compound climate impacts are causing longer, larger declines in the abundance of seagrass, mangroves and key fisheries such as prawns. In addition, as climate change extremes ramp up impacts on marine and coastal ecosystems, breakdowns of river-coastal-ocean connectivity likely lead to changes in species spatial distribution. The consequences are akin to a wild roller coaster ride for many species and challenges how management should respond and adapt.
Conclusion
A range of tailored management approaches are needed to support ongoing sustainable management of fisheries and biodiversity across tropical northern Australia and other similar marine ecosystems. We share examples related to changes to stock assessments, harvest strategies, catchment management and conservation planning.