Risks to the Region’s values
9.4 Assessment summary — Risks to the Region’s values
Section 54(3)(d) of the Great Barrier Reef Marine Park Act 1975 requires ‘… an assessment of the risks to the ecosystem…’ within the Great Barrier Reef Region. Section 116A(2)(b) of the Regulations requires ‘an assessment of the risks to the heritage values…’ of the Great Barrier Reef Region. Separate assessments are provided for the Region’s ecosystem and its heritage values, based on their current state and trends, the factors influencing them, the effectiveness of protection and management measures and an understanding of their overall resilience.
9.4.1 Risks to the ecosystem
Outlook Report 2009: Assessment summary The ecosystem is at serious risk from the compounding impacts of climate change, catchment runoff, coastal development and extractive use. Of the many other threats to the Great Barrier Reef ecosystem, most present a small risk individually, but combine to further reduce ecosystem resilience. Other threats are effectively managed and are now assessed as a much reduced risk.
Current summary and assessment components Overall risk to ecosystem: The Region’s ecosystem continues to be at serious risk and the threats likely to affect it in the future are increasing and compounding. The most serious risks arise from climate change, land-based run-off, coastal development and some aspects of direct use (particularly fishing). Other threats relating to direct use are more effectively managed and of less overall risk to the Reef. Climate change: The threats of sea temperature increase, altered weather patterns, ocean acidification and sea level rise continue to be some of the most serious risks to the Reef ecosystem. The risk is likely to increase in the future due to emissions trajectories and unavoidable future change locked in by past emissions. Coastal development: Clearing and modifying coastal habitats and artificial barriers to flow are serious risks to the Reef. Increased coastal development increases the likelihood of these threats. Direct use causes demand for some aspects of coastal development. Land-based run-off: While loads of nutrients and sediments are being reduced, understanding of the detrimental effects on the ecosystem has improved. The continued inputs and the lag between reduced inputs and improved ecosystem condition mean that nutrients, sediments and pesticides in land-based run-off will continue to be a serious long-term risk to the ecosystem. Marine debris from all sources will also remain a high risk. Direct use: Many threats from direct use are localised and of low to medium risk. However, some significant risks remain. Illegal fishing and collecting, extraction of predators, extraction from unidentified or unprotected spawning aggregations, incidental catch of species of conservation concern and effects on discarded catch are rated as high or very high risk. Although overall risk from ports is assessed as medium, increases in port-related activity combined with future projections and a continued incomplete understanding of the potential ecosystem effects have increased the assessed risk for disposal and resuspension of dredge material.
Assessment grade and trend
Low risk Medium risk High risk Very high risk Grade Trends
h h n
Given current management arrangements, any threats considered likely or certain to occur are predicted to have no more than insignificant consequences for the ecosystem. There may be minor or moderate consequences for the Region’s ecosystem for other less likely threats.
Trend since 2009
Given current management arrangements, few of the threats considered likely or certain to occur are predicted to have moderate consequences for the Region’s ecosystem and none will have catastrophic consequences. Some unlikely threats may have major consequences for the Region’s ecosystem.
Increasing Stable Decreasing No consistent trend