In 1969, about 900 tourists visited the tiny Caribbean island of Roatán, off the coast of Honduras. In 2000, about 100,000 visited. In 2011, more than 1,000,000 people came. The effect of that visitor uptick on the island is clear, thanks to images taken by the same National Aeronautics and Space Administration satellite in both 1985 and 2015:
Tourism doesn't have to hit the natural land so hard. "There is an interesting contradiction playing out on Roatán," Cascade Tuholske, a doctoral student in geography at the University of California–Santa Barbara, told NASA's Earth Observatory. "On the northern coast in the areas of Sandy Bay and West End, the island's development has led to increased marine conservation awareness and the establishment of marine protected areas. On the southern coast, the boom in tourism is causing increased ecosystem damage through the cutting of mangroves, sewage runoff, and increased garbage."
Meanwhile, not developing sustainably isn't just harmful for local mangroves and coral reefs; it's bad for people too. Environmental degradation in Roatán has been linked to an increase in sickness rates, from diseases caused by poor sanitation, Tuholske said. Environmental degradation might also be the driving force behind an increase in mosquito-borne diseases such as dengue fever and chikungunya.