Coral reefs are amongst the most productive areas of the ocean. Each coral contains microscopic algae within its tissue that are able to capture the energy of the Sun and convert it into food. The corals benefit from this, and this helps support a whole community of life. There’s a tight recycling of nutrients through the food web, every species being food for another, all interconnected like a jigsaw puzzle.

Reefs are ocean nurseries: they may cover less than 1% of the ocean floor, but support about 25% of all marine creatures. And there’s almost no other habitat on Earth that does more for humans. Hundreds of millions of people live close to coral reefs, and local communities rely on the reefs to survive. Many costal villages don’t have access to deep-sea fishing resources, their only access to nutrients like protein live on the reefs. They also rely on reefs as sources of tourism revenue, and as storm buffers.

Local fishing may be sustainable, but many reefs are under pressure from international fishing fleets and from the problems posed by climate change. A third of reef-building corals are in danger of extinction, and reefs all over the world are in serious decline.

If they are going to see through this period of great change in the oceans, coral reefs need to be as resilient as possible, and that means reducing manageable stresses like exploitation pressures, as well as increasing protection. Protecting coral reefs will help the sea to help itself – these are centres of production that replenish the surrounding waters that fishermen depend on.

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