More specifically, our focus is primarily the near shore but deep-sea habitats. The Coral Triangle hosts some of the deepest water on the planet – also known as ‘Planet Deep’.   Planet Deep is the second deepest place on our planet, and has by far the most extreme habitat diversity and near shore proximity. The Banda Sea has volcanic island drop offs plummeting to nearly 4000m, the New Britain Trench in the Solomons plunges to a maximum depth of 9140m and the Philippine Trench in the Pacific Ocean is listed as the fourth deepest expanse of water in the world, with a mind boggling depth of 10,540m. All of them remarkably near shore.

This is our area of particular interest – the coral reef-to-abyss interactions:

• Migratory (and ecological) corridors
• Canyons, trenches and sills
• Seamounts – extremely high levels of biodiversity and endemicity
• Vents and pinnacles
• Persistent pelagic habitats; for example, seasonal upwelling zones and oceanic fronts
• Large-scale current systems
• Drop-offs near oceanic islands

The shading of the seas on this map, taken from Google Earth, clearly shows the gradients and the plummeting depths, as the blue turns almost black.

Deep-sea and oceanic habitats, threats and species are important to consider when designing and evaluating MPAs and MPA networks for biodiversity conservation in Indonesia. These habitats are also often located close to shore due to extreme depth gradients, creating opportunities for ecotourism.

Planet Deep’s focal species are:

• Oceanic cetaceans – migratory and residential species, including: blue, sperm, beaked and Brydes whales, and dolphins
• Marine turtles
• Oceanic sharks and rays (e.g. whale sharks and mantas),
• Sunfish
• Billfish and tuna
• Benthic – diverse yet vulnerable communities associated with seamounts and other deep-sea features

These deep-sea habitats and species are a high priority for conservation, and most CT member states have already committed to protecting them through national legislation; for example, all marine mammals are protected under national law, as well as through various international treaties (i.e. UN SDG, CBD, CITES), regional action plans such as the Coral Triangle Initiative Regional Plan of Action, and national species-specific action plans.