But an alien species has invaded this tropical haven. Humans they have been living here for more than a century. But in the past few decades, tourism has skyrocketed. And workers from the mainland have followed in the wake to open businesses and provide services. Some estimate the permanent population on the islands has increased by as much as 300%. “In 1980s, there was a local population of about 3,000 people living here in the islands, and today we have a local population of more than 25,000 people.”