COCOS ISLAND - COSTA RICA Here, sharks and dolphins herd schooling prey into a whirling sphere near the surface called a bait ball. Fish caught in the vortex become quick meals for diving seabirds from above and charging predators from below.
Situated just north of Madagascar in the Indian Ocean, the Seychelles are a remote archipelago of 115 islands. Though the islands are known as a celebrity vacation destination, they hold natural treasures far greater in value. The outer Seychelles.
A lemonpeel angelfish ( Centropyge flavissima) observed at Henderson Island, by the National Geographic Pristine Seas expedition to the Pitcairn Islands. Photograph: Enric Sala/National Geographic/Courtesy of Pristine Seas
Hammerhead Shark Schools of hammerheads stop by Cocos during their long migrations to visit the island's so-called "cleaning stations," where smaller fish consume parasites on the sharks' skin and in their gills and mouths. Cocos Island Expedition Photos -- National Geographic