The world’s largest living organism, Australia’s Great Barrier Reef, faces a rising risk of destruction. A new study concludes that, due in part to climate change, the World Heritage-protected site has a “poor” chance of survival. One of the most diverse ecosystems in the world, the reef contains important species like dugongs, marine turtles, seabirds, and some sharks, whose populations are declining. Meanwhile, coral diseases and pest outbreaks are on the rise. “Even with the recent management initiatives to improve resilience, the overall outlook for the Great Barrier Reef is poor and catastrophic damage to the ecosystem may not be averted,” a government reef management body said in the outlook report, which is produced every five years and benchmarks the health of the reef. It found that climate change, worsening water quality due to coastal runoff, development and illegal fishing all posed a threat to the reef, which stretches over 345,000 km off Australia’s east coast, Reuters reports.