British Indian ocean territory (the Chagos archipelago) : setting, connections and the marine protected area

The British Indian Ocean Territory consists of the Chagos archipelago, almost all of which was designated a no-take MPA in 2010. It covers 650,000 km2, with >60,000 km2 shallow limestone platform and reefs. This has doubled the global cover of such MPAs. It has strong biological affinities with the western Indian Ocean, and larval travel time to reefs to the west of it is 25–35 days. Genetic work is only recently commencing, but it is likely to be a cross-roads, or bridge, in this respect. A licensed fishery used to exist, but this too was closed in 2010, and the large diameter of the area may prove to be a significant reserve for pelagic fishes such as tuna also. The region probably contains about 300 sea mounts and knolls, which is about 10 % of all Indian Ocean seamounts and nearly half of all those protected worldwide, and so the area is regionally important for these features as well with their unexplored but probably diverse deep benthic and fish biota. The area is also well placed to fill a large gap in global monitoring systems; it is located in key region of climate variability, so programmes carried out there are particularly important to research into climate change effects also. The area has very high conservation value and is an important biological asset in an ocean where most reefs show significant and continuing decline in health.