And since Castro seized power in 1959, logging has slowed significantly. Forest cover has increased from 14 percent in 1956 to about 21 percent today.
In addition, the more than 4,000 smaller islands surrounding the main island are important refuges for endangered species. The coastline and mangrove archipelagos are breeding grounds for some 750 species of fish and 3,000 other marine organisms.
"Because Cuba's tourist industry has not developed quickly in regard to reef exploitation, the reefs have been spared the fate of Florida's reefs, for example," Gebelein said.
At about 1.5 million acres (600,000 hectares), the Ciénaga de Zapata Biosphere Reserve is Cuba's largest protected area and has been designated a "Wetland of International Importance" by the Ramsas Convention on Wetlands in 1971.
"The Zapata Swamp is the Caribbean's largest and most important wetland," said Jim Barborak, who is based in San Pedro, Costa Rica, and heads the protected areas and conservation corridors program for Conservation International.
Jewel of the Caribbean
Originally, Cuba was in the Pacific Ocean, not the Caribbean Sea. Continental drift slowly brought the island into the Caribbean some 100 million years ago, and an astonishing variety of life emerged.
"Cuba has tremendous biological diversity," Barborak said. "The levels of plant endemismunique species limited to Cubais particularly high, especially in highland ecosystems in eastern Cuba."
More than half of Cuba's plants and animals, and more than 80 percent of its reptiles and amphibians, are unique to the island.
Endemic birds include the Cuban trogon, the Cuban tody, and the Cuban pygmy owl. The world's smallest bird, the bee hummingbirdwhich weighs less than a U.S. pennyis found there.
"Important populations of many North American migratory birds, whose declining populations require international action to conserve both breeding and wintering grounds, spend much of the year in Cuba," Barborak said.
Cuba is only one of two nations with a primitive mammal known as a solenodon, a foot-long (0.3-meter-long) shrewlike creature.
The island also has a great diversity of giant lizards, crocodiles, and tortoises.
A key player in Cuba's green movement has been Guillermo García Frías, one of five original "comandantes" of the 1959 Cuban revolution.
A nature lover with strong ties to Castro, García has pushed for a strong environmental ethic for a generation of scientists and government officials.
"Comandante García's enthusiasm for nature conservation has been critical to the successful development of a conservation infrastructure in Cuba," said Mary Pearl, president of the Wildlife Trust in New York City.
Cubans are leaders in biological research, with thousands of graduates from the country's ten universities and institutes devoted to work in ecology.
"The country has the best intellectual infrastructure for wildlife conservation in the Caribbean," Pearl said.
Students in every department at the University of Havana, for example, have had the opportunity to share a bonding experience by living in an impoverished fishing village while working to protect marine turtles.
"As a result, many of Cuba's leaders in all spheres have had a common experience reconciling poverty alleviation and nature conservation," Pearl said. "It is not surprising that this has left a legacy of concern for nature, despite the country's economic challenges."
But Cuba has earned its green credentials partly by default.
Isolated in part because of the U.S. trade embargo against the island, Cuba has been excluded from much of the economic globalization that has taken its toll on the environment in many other parts of the world.
"The healthy status of much of the wetlands and forests of Cuba is due not to political influence as much as the lack of foreign exchange with which to make the investments to convert lands and introduce petrochemical pesticides and fertilizers," Pearl said.
Since the collapse of the Soviet Union, many Cuban factories and agricultural fields have sat dormant. The island has had to become self-sufficient, turning to low-energy organic farming.
It has had to scrap most of its fishing fleet because it can't afford to maintain the ships.
Population pressure has also been a nonissue, with many Cubans fleeing the country for economic and political reasons.
However, Conservation International's Barborak says it would be wrong to think Cuba's environmental success is simply due to its economic underdevelopment.
"If this were true, then Haiti could be expected to be a verdant ecological paradise, instead of being the most environmentally devastated country in the region, with just a tiny fraction of its forest cover intact," he said.
"Cuba's stable population, high literacy rate, clear land-tenure system, large cadre of well-trained conservationists, and relatively strong enforcement of laws and regulations are certainly all associated with its conservation achievements."
So what will happen if Castro's regime falls and a new, democratic government takes root?
Conservationists and others say they are worried that the pressure to develop the island will increase and Cuba's rich biodiversity will suffer.
Barborak said he is concerned that "environmental carpetbaggers and scalawags will come out of the woodwork in Cuba if there is turbulent regime change.
"One could foresee a flood of extractive industries jockeying for access to mineral and oil leases," he said.
"A huge wave of extraction of unique and endemic plants and animals could occur to feed the international wildlife market. And a speculative tourism and real estate boom could turn much of the coastline into a tacky wasteland in short order."
"If foreign investments take a much firmer hold, more hotels will be built and more people will descend on the reefs," added Gebelein, the Florida International University professor.
"If the Cuban government does not have a swift policy framework to deal with the huge influx of tourists, investors, and foreign government interests, a new exploitative paradigm will be the beginning of the end for some of the last pristine territories in the Caribbean."
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