Ecuador declared the world-famous Galapagos Islands at risk and could temporarily suspend tourism permits and enforce rigorous population restrictions to prevent further environmental harm.
"We are pushing for a series of actions to overcome the huge institutional, environmental and social crisis in the islands," President Rafael Correa said after signing an emergency decree to help the archipelago.
Correa did not provide any details about the possible restrictions, but said the country would consider suspending some tourism permits. Thousands of visitors travel to the Galapagos annually.
The volcanic islands, located 625 miles (1,000 km) west of Ecuador's coast, inspired British naturalist Charles Darwin's theory of evolution. A growing population, illegal fishing of sharks and sea cucumbers, and internal bickering at the national park have taken a toll.
"The government needs to be stricter on what is allowed there as pressure on Galapagos grows," said Martin Wikelski, a biologist at Princeton University. "It is one of the world's most unique ecosystems... and continues to be one of the most important laboratories for evolution studies."
Centenarian tortoises and blue-footed boobies live alongside 18,000 islanders who earn a living from fishing and a growing tourism industry.
About 15,000 people are believed to live illegally in the islands, government officials said.
A United Nations delegation is visiting the islands to determine whether the World Heritage site should be declared "in danger."