The park exists because of geology. Established by Decree 571-09 under IUCN Category II protection, Parque Nacional Anacaona was created to preserve the virgin forests of the eastern Sierra de Neiba and the dramatic landforms left behind when tectonic shifts rerouted the Yaque del Sur River. The river's old channels carved canyons and meanders through the mountainous terrain, creating a landscape that rises from 80 meters above sea level to 950 meters at its peaks. That nearly nine-hundred-meter range of elevation compresses several climate zones into a single park. Temperatures drop from 25 degrees Celsius in the exposed lowlands to 23 degrees in the humid mountain forests, and annual rainfall swings from 400 millimeters in the driest valleys to 1,000 millimeters at the highest ridges. The result is a park where you can walk from cactus-studded desert into mahogany forest in a single day.

In the middle of all this aridity sits Laguna Caney, a freshwater wetland that has no business existing where it does. Surrounded by dry forest on every side, this small high-altitude lagoon functions as a biological refugium -- a pocket of moisture that supports species otherwise absent from the surrounding landscape. The contrast is stark. Walk toward the lagoon through stands of drought-tolerant mesquite and gumbo-limbo trees, and the vegetation shifts almost abruptly into something greener, denser, wetter. The lagoon collects water that the surrounding terrain cannot hold, creating a micro-habitat that serves as a lifeline for amphibians, fish, and waterbirds that would otherwise have no foothold in this part of the island. Portions of the Yaque del Sur River and its tributaries also thread through the park, feeding the agricultural valleys below -- a reminder that this protected area is not isolated from the communities around it.

Two iguana species share this territory, and their fates could not be more different. The rhinoceros iguana, Cyclura cornuta, is relatively common -- a heavy-bodied reptile whose horn-like scales give it its name. Its cousin, Ricord's iguana, Cyclura ricordii, is critically endangered, one of the rarest lizards on Earth. Both inhabit the park's dry forests, but Ricord's iguana clings to existence in a shrinking range. The park is part of the Hispaniolan Endemic Bird Area, sheltering the Hispaniolan amazon parrot, the broad-billed tody, and the white-fronted quail-dove. Six species of anole lizards partition the habitat by perch height and sun exposure, each occupying a niche so specific that they can coexist on the same hillside without competing. Endemic snakes -- the Hispaniola racer and Ford's boa among them -- hunt through the undergrowth. In the park's few water bodies, Hispaniolan cichlids and native livebearers swim alongside freshwater turtles.

Vegetation in the park follows elevation like a script. The lowlands belong to mesquite and gumbo-limbo, trees built for drought -- shallow-rooted, thick-barked, stingy with their leaves. Climb into the mid-elevation zones and the forest changes character. West Indian mahogany and torchwood replace the desert species, their canopies growing denser as moisture increases. Higher still, where clouds settle against the Sierra de Neiba, the forest becomes something else entirely: autograph trees and lancewood laurels dripping with epiphytes, their roots gripping soil that stays wet year-round. This altitudinal gradient is the park's organizing principle, sorting species into bands as clearly as contour lines on a map. Each band has its own temperature range, its own rainfall budget, its own community of plants and animals adapted to conditions that shift dramatically within a few hundred meters of elevation.

The park is not untouched. Feral pigs root through the understory, disturbing soil and destroying ground-nesting sites. Creole goats browse on native vegetation, preventing forest regeneration in areas already stressed by drought. Illegal wood harvesting thins the forest canopy, particularly in the more accessible lowland zones where hardwoods fetch the highest prices. These pressures are not unique to Anacaona -- they shadow protected areas across the Caribbean -- but they carry special weight here, where the park shelters species found nowhere else. The critically endangered Ricord's iguana cannot afford to lose more habitat. The endemic fish in the park's streams have no backup populations elsewhere. Conservation here is not about preserving scenery. It is about holding the line for species that have already been pushed to the edge of their range, on an island where that edge keeps moving.