Hard Corals

Hard Corals Latest News

A major new assessment by the Global Coral Reef Monitoring Network (GCRMN) has reported a dramatic decline in hard coral populations across the Caribbean.

About Hard Corals

• Hard corals, also known as stony corals, are marine animals that build the limestone frameworks upon which reefs form.
• They grow in colonies and are often referred to as “reef-building corals.”

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Key Features of Hard Corals

• They are composed of thousands of tiny polyps that secrete calcium carbonate.
• Hard corals create skeletons out of calcium carbonate, a hard substance that eventually becomes rock.
• Over time, this rock builds up to form the foundation of a coral reef and provides a structure upon which baby corals can settle.
• These corals depend upon tiny algae called zooxanthellae that live inside them. 
• They share a symbiotic relationship (the corals provide the zooxanthellae with shelter, and in return, the zooxanthellae provide the corals with food).

Threats to Hard Corals

• Bleaching events driven by extreme heat
• Stony Coral Tissue Loss Disease: It is spread across 30 countries which is causing unprecedented mortality of corals.
• Losses of key herbivores such as the Diadema sea urchin have fuelled an 85% surge in macroalgae.

Source: DTE