CORAL REEFS ‘Coral reefs are amongst the oldest and largest living structures on Earth. Climate change, pollution and overexploitation are seriously threatening their survival’ BIOSPHERE EXPEDITIONS
Corals are anthozoans, the largest class of organisms within the phylum
COMMON NAME: Coral reefs
Cnidaria (corals, hydras, jellyfish, and sea anemones), comprising over 6,000
SCIENTIFIC NAME: Coral polyps belong to a group of animals known as Cnidaria, which also includes sea anenomes and jellyfish.
known species. A group called stony corals is primarily responsible for laying the foundations of, and building up, reef structures by secreting calcium carbonate skeletons. Different species of coral build structures of various sizes and shapes (“brain corals,” “fan corals,” etc.), creating amazing diversity and complexity in the coral reef ecosystem. Coral reefs form some of the world’s most productive ecosystems, providing complex and varied marine habitats that support very high biodiversity. Coral reefs deliver ecosystem services to tourism, fisheries and coastline protection. Their global economic value has been estimated at as much as GBP 250 (USD 375) billion per year. Many small islands would simply not exist without their reefs to protect them. But coral reefs are dying around the world. Coral mining, pollution, overfishing, blast fishing, disease, and the digging of canals are localised threats to coral ecosystems. Broader threats are sea temperature rise, sea level rise and pH changes from ocean acidification, all associated with global climate change. Today the majority of reefs are threatened or severely degraded. By the 2030s, 90% of reefs are expected to be at risk; by 2050, all coral reefs will be in
STATUS: 10% of the world’s coral reefs are dead, about 60% are at risk, particularly in Southeast Asia, where 80% of reefs are endangered. POPULATION: Coral reefs are estimated to cover 284,300 sqkm or just under 0.1% of the oceans’ surface area. LIFESPAN: Most coral reefs were formed after the last glacial period about 10,000 years ago. RANGE: Tropical seas within 30 degrees either side of the equator. THREATS: Climate change, pollution, human impact, overfishing/ exploitation.
danger. Through research and conservation work, Biosphere Expeditions and many other organisations are working on turning the tide.
What you can do… • Join a coral reef research and conservation expedition. Biosphere Expeditions run these in Oman, Malaysia, the Maldives and Honduras – www.biosphere-expeditions.org. • Join Reef Check www.reefcheck.org, an international conservation organisation dedicated to reef conservation. 2 going going gone