Locations
The Indian Ocean

The Indian Ocean is the third largest body of water on Earth at more than 6,000 miles wide and covering 13% of the world's surface. It is home to 5,000 species of fish, many of which only exist in the Indian Ocean. But it is also an ocean under threat from global issues such as over-fishing and climate change, which make this an ocean on the edge.
Coral nursery
The marine diversity found on coral reefs supports a billion people yet 25 per cent of the world's reefs are at risk and around a third of Indian Ocean coral has disappeared. Threats include climate change, coastal development and the crown-of-thorns starfish. In one instance numbers of this coral predator increased 100 fold. This may have been due to overfishing of starfish predators.

In a man-made coral garden 20 metres below the surface off Chumbe, Tanzania, more than 9,000 tiny coral fragments taken from healthy reefs are nurtured in a protected environment where blanketing algae is removed. Relocating these established corals onto damaged reefs may help reverse their decline. Scientists hope that using mature specimens will increase the success rate of coral transplantation.
| Importance: | Coral reefs, vital nurseries for many fish species, are under threat worldwide. Stopping their rapid decline is vital for the health of the oceans. |
| Dive category: | Charter companies offer snorkelling and scuba trips to reefs near the Chumbe Reef. The best ones ensure there is no impact on this fragile ecosystem. |
| Access: | Chumbe Island Coral Park is a privately run marine park and eco resort. Diving the Chumbe Reef is prohibited unless for scientific purposes. |
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