Great Barrier Reef

Spanning approximately 348,000 square kilometers, the reef system stretches over 2,300 kilometers along the Australian coastline. It is composed of roughly 3,000 individual reefs and hundreds of islands and cays. This massive ecosystem supports thousands of species, including over 1,600 types of fish and more than 600 species of coral, making it one of the most biodiverse natural systems on Earth. The reef has experienced frequent and increasingly severe mass coral bleaching events, which occur when prolonged high ocean temperatures cause corals to expel the algae living in their tissues. According to the Australian Institute of Marine Science, mass bleaching events have been documented in 1998, 2002, 2016, 2017, 2020, 2022, 2024, and 2025. Research indicates that the frequency of these events has increased significantly in recent years, leaving corals with insufficient time to recover between heat stress episodes. Management of the reef is a complex challenge, primarily overseen by the Great Barrier Reef Marine Park Authority. Climate change is identified as the greatest threat to the ecosystem, driving the rising ocean temperatures that trigger bleaching. This global pressure is compounded by local stressors, including pollution and sediment runoff from agricultural and industrial activities on the mainland, which degrade water quality and further weaken the reef's resilience. Efforts to protect the reef involve a combination of local management strategies, such as improving water quality and controlling outbreaks of the coral-eating crown-of-thorns starfish, alongside the urgent need for global action to reduce greenhouse gas emissions. Despite these interventions, scientific assessments warn that the window of opportunity to secure a positive long-term future for the reef is closing as global temperatures continue to rise.