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 risks to Great Barrier Reef ecosystem

• Extent and timing of threats and their driving factors

• Effectiveness of existing management for identified risk factors

Assessment component summaries

Climate change

The threats of increasing sea temperature, ocean acidification and sea level rise are very high risks to the ecosystem.

• Factors influencing the reef's values - climate change

Catchment runoff

The threats of nutrients, pesticides and sediments from catchment runoff are high and very high risks to the ecosystem.

• Factors influencing the reef's values - catchment runoff

Coastal development

Clearing of coastal habitats is a high risk to the ecosystem, as is the threat of ingestion of marine debris by species of conservation concern.

• Factors influencing the reef's values - coastal development

Direct use - extractive

There are a number of threats associated with fishing and traditional use. Extraction of top predators is a very high risk to the ecosystem, others are of either high (such as illegal fishing) or medium risk.

• Factors influencing the reef's values - direct use

Direct use - non-extractive

There are a number of threats from non-extractive use, generally of low to medium risk. Large chemical and oil spills, although unlikely, could be of major consequence.

• Factors influencing the reef's values - direct use