Locations
The Indian Ocean - coastal waters

The tropical Indian Ocean is home to the Spice Islands. Characterised by beautiful sandy beaches, fringing coral reefs and coastal mangrove forests, this is a vibrant nursery area for marine life, such as whale sharks, crabs, seahorses and a great variety of fish. The coastal areas are where humans have the most direct impact on the ocean's resources.
Coral reef off Pemba Island
The biodiversity of life on a coral reef can be greater than that in a rainforest. At night the animal part of the reef - the polyp - emerges to feed. Armed with stinging cells, its tentacles reach out to hunt prey as currents bring food from the depths.

Some corals grow about 1cm a year, so large corals, like the table corals found here, often indicate a healthy ecosystem. The great variety of coral species found here include staghorn and pineapple coral. Corals compete for prime position where there is the greatest exposure to the sun. At night, slow-growing corals emit toxins to fend off faster growing rivals. These night battles keep the reef ecosystem healthy, as no one single coral dominates.
| Importance: | The health of coral reefs is an important indicator of the state of the world's oceans. These habitats are fragile and easily damaged by human activity. |
| Dive category: | Night dives, a great way of seeing how coral reefs transform at night, should be undertaken with training in how to communicate and navigate underwater in the dark. |
| Access: | Several specialist operators on Pemba Island offer night dives to the coral reefs around the island. |
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