CROCODILE ISLAND

Welcome to Lago Enriquillo: the undisputed crocodile capital of the Caribbean

- JOSEPH PALMER

LAGO ENRIQUILLO IS A LAKE THAT DEMANDS description in superlatives. Stretching across an arid valley in the south-west corner of the Dominican Republic, near the country's border with Haiti but far from the holiday hubs of Punta Cana and Puerto Plata, the lake is unique, in the most literal sense of the word. To start with the basics, it is the country's largest lake. In fact, Lago Enriquillo is the largest lake in the entire Caribbean.

The lake's most extraordinary features, however, are found in its exceptional ecology. Among other distinctions, it is home to the world's largest population of American crocodiles, themselves one of the largest crocodilian species in existence. The largest males reach 6m in length. American crocodiles are also one of only two crocodilians to thrive in saltwater, along with Australia's famous 'salties'.

This saltwater tolerance is relevant because, despite being inland and river-fed, Lago Enriquillo is a saltwater lake. Moreover, it is a hypersaline lake, up to three times saltier than the ocean. At 46m below sea level, Lago Enriquillo's shoreline is the lowest elevation found on any ocean island in the world (yet another superlative). To merge with the Caribbean Sea, its waters would have to flow uphill.

The lake's submarine altitude is a result of events that occurred in the area's deep geologic past. Today, Hispaniola (the large island that comprises both the Dominican Republic and Haiti) is a single, relatively large island. Millions of years ago, however, it was two smaller landmasses: one larger island that became the bulk of modern Hispaniola, and a second, smaller island that became the southwestern Dominican Republic and southern Haiti (this geology lesson will be relevant later).