The Ocean

Photo: Silver tip sharks swimming near Cocos Island
A school of sharks lurks just below the ocean surface near Cocos' rocky shore.

Photograph by Octavio Aburto

Cocos Island and the Gemelas Seamounts

In September 2009, National Geographic Fellow Enric Sala, National Geographic Explorer-in-Residence Sylvia Earle, and a team of leading marine scientists from Central America and across the globe gathered together in Costa Rica. Destination: Cocos Island—Isla del Coco, ringed by some of the most shark-rich waters anywhere—and the submerged and all-but-unexplored summits of the Gemelas (“Twin Sisters”) Seamounts.

The team worked with local marine scientists and conservation organizations to document these aquatic ecosystems. The data, they hope, will help to establish new scientific baselines for intact—and critically important—environments.

While Cocos has helped define the world’s image of an untouched island paradise for centuries, the Gemelas Seamounts have lurked, mostly unseen and unknown, beneath hundreds of feet of seawater. But marine creatures know them as fertile and important waypoints on their wanderings. These rich feeding grounds may be critical to the survival of many of the migratory predators that pass through them.


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