Off the coast of East Africa in the Zanzibar archipelago, rest the island of Pemba and islet of Kokota. When Mbarouk Mussa Omar toured Kokota a decade ago, it was teetering toward the brink of collapse. Deforestation and climate change had wreaked havoc on the tiny islet. He realized that his island of Pemba could experience the same future and decided to do something. A National Geographic production.