What is the state of the Great Barrier Reef?
The Great Barrier Reef Outlook Report 2024, prepared every five years by the Great Barrier Reef Marine Park Authority, summarises the Reef’s long-term outlook based on its use, management, and risks. This year’s report uses data from the Australian Marine Debris Initiative Database to analyse the risks and impacts of marine debris on the Great Barrier Reef and help identify areas for improvement.
"The window of opportunity to secure a positive future for the Great Barrier Reef (the Reef) is closing rapidly."
The report warns that due to climate change impacts, further degradation of the Reef is inevitable. While the Reef shows signs of resilience, with some coral conditions improving, marine turtle populations have further declined, and many are now threatened.
"The Reef ecosystem, the people who use and depend on it, and human wellbeing are deeply interconnected."
Efforts to reduce greenhouse gas emissions, meet water quality improvement targets, address compounding threats and support the Reef’s natural resilience will be prioritised, including protecting species and habitats critical for resilience.
Impacts of Marine Debris
The report acknowledges marine debris (from both local and distant sources) as an emerging threat to the Region’s wildlife that can have wide-ranging impacts on the environment, economy and human health.
"Given the rapid increase in plastic production globally, the longevity of this material, and the disposable nature of plastic items, plastic marine debris is likely to persist into the future and be present at a broad scale within the Region."
The report identifies marine debris impacts, including:
- damage to reef structure
- harm to marine animals, including those of Indigenous cultural significance
- harm to culturally important areas and sacred sites
- Loggerhead turtle fishing gear entanglement and ingestion of plastic by small post-hatchlings (high-risk)
- Humpback whale fishing gear entanglement
Marine Debris Data
- The quantity and relative contributions of marine debris vary from north to south. Between 2019 – 2022, the heaviest mass of debris (10,231 kilograms) was collected in the Cape York region. Since 2020, more than 85% of the debris in every zone of the Cape York region is predicted to have come from offshore sources.
- Remnant plastic pieces (hard and solid), plastic lids and tops, and pump spray and flow restrictors remained the most common marine debris.
- Microplastics are consistently detected in surface waters and can represent up to 50% of debris in some areas. However, surveys (2019 to 2023) revealed that microplastic loads are generally lower than in other Australian regions.
Although knowledge of the quantity and ecological effects of marine debris and microplastics is improving, gaps remain. More research is needed into the frequency, source and broader wildlife interactions.
