Vanishing Dragons

A bewitched world - inhabited by Dragon and creatures that seem from another world! That's Galapagos. For Millions of years these animals have survived and adapted to hostile conditions. But now the seemingly prehistoric marine iguanas seem to reach the limits of their adaptability. In the last 15 years, the population has shrunk by several hundred thousand animals. What is it that bothers the mini-dinosaurs? What can one do to prevent the demise of Godzilla's little heirs?