Cocos Island lies 340 miles off the coast of Costa Rica in the eastern tropical Pacific. Another 400 miles south are the Galapagos Islands. Both are considered safe havens for wildlife, and the waters surrounding each area are protected.
Between the two islands is a busy underwater highway for migratory fish. Species such as sea turtles and sharks move back and forth between the marine reserves, looking for places to nest or foraging for food.
But the underwater highway is open to fishing activities, and with populations of the migratory species declining, scientists and conservationists are campaigning for the entire swimway to be protected.
MigraMar, a network of scientists and environmental groups, has built a strong case for protecting the swimway, by documenting the species that use it. They have attached satellite and acoustic tags to individual species, like the whale shark pictured, so that they are able to follow their migratory pathway.