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U.K. Establishes Record-Breaking Marine Reserve

Middle Brother Island, Chagos Archipelago.
Credit: Anne & Charles Sheppard

The United Kingdom announced today that it will create the world's largest marine reserve in its territorial waters in the Indian Ocean. The move will help protect 544,000 square kilometers—an area larger than California—and some of the most remote and pristine reefs anywhere. The reserve is so big that it increases by 73% the amount of ocean where fishing is banned (to about 0.33%). "It's terrifically exciting," says Jay Nelson of the Pew Environment Group, which advocated for the new reserve.

The Chagos Archipelago boasts the largest coral atoll in the world and many smaller reefs. The 55 islands host rich colonies of seabirds, endangered turtles, as well as undisturbed populations of giant coconut crabs.

Short tentacle plate coral.
Credit: Anne & Charles Sheppard

Charles Sheppard, a coral reef ecologist at the University of Warwick in Coventry, U.K., has studied the Chagos area since the 1970s. His research and that of some 50 other scientists has demonstrated the remarkable diversity of the reefs, he says. "It's like a time machine, going back to the 1950s" when reefs were much healthier than today, he says. That makes the reefs a valuable point of comparison for managers trying to restore damaged reefs elsewhere.

The Chagos reefs appear to be extremely resilient. Unlike other reefs in the Indian Ocean, which suffer from pollution and overfishing, the Chagos Archipelago rebounded quickly from a 1997-1998 "bleaching" event, when warmer-than-average waters harmed many corals. This resilience suggest the reefs have a better shot at surviving the two main threats that climate change poses to reefs--warmer and more acidic water.

Clownfish and anemone
Credit: Alasdair Harris, Blue Ventures Conservation

Fishing and other harvesting will be banned in the new reserve. Currently, two kinds of tuna, skipjack and yellowfin, are legally caught in the area. Poachers kill sharks for their fins, and collect sea cucumbers for export to Asia. Currently only one fisheries enforcement vessel patrols the Chagos Archipelago (it also serves as the lone research vessel). Nelson says the Pew Environment Group has commissioned a study about enforcement needs. "We're quite confident that with the resources that they have now, and a little enhancement, they can basically make the area pretty bulletproof."