A group of sailors, scientists, and filmmakers followed them aboard the ocean schooner Sedna IV, circumnavigating the world to explore the beauty of nature, how ecosystems function, and the conservation challenges facing the planet. 1. The sharks on Cocos Island emphasize the efforts made to protect them from overfishing. 2. The song of the humpback whale: Scientists attempt to decipher the secrets behind the humpback whale's song. A biologist from the Barrow Colorado Island Research Center in the central Panama Canal introduced the rare dwarf three toed sloth to the crew of Sedna IV and explained the reasons why the species is threatened. The Cayman Islands emphasize the efforts made to save the Grand Cayman blue iguana from extinction. Five scientists are studying the last jaguars in a private protected area in Costa Rica. In addition, studying how the transformation of forests into farmland poses a threat to their population. The Belize manatee highlights the work of researchers in protecting manatees in Belize. 7 Costa Rican sea turtles - look at the threats faced by sea turtles nesting on Costa Rican beaches. Including the struggle between environmentalists and poachers.