The lagoon is the estuary of the Tonameca River, cut off from the sea by the beach for much of the year and threaded with mangroves whose roots create a labyrinth of narrow channels. Two species dominate: red mangroves, whose root tannins stain the shallows a reddish hue and turn deeper water nearly black, and white mangroves, which prefer the slightly higher ground at the lagoon's edges. In the mornings, the soundscape belongs to birds - woodpeckers, kingfishers, ducks, storks, cormorants, herons - layered over the ambient hum of insects and the occasional splash of something larger moving through the water. That something larger is usually a crocodile, the lagoon's main attraction for tourists, though iguanas, deer, crustaceans, and freshwater turtles share the habitat. During the rainy season, the lagoon breaches the sandbar and connects to the ocean, drawing sea turtles, dolphins, and fish into the estuary to feed.

Before 1997, the main lagoon was surrounded by trees reaching thirty-five meters in height, with mature mangroves filling the waterways beneath their canopy. Hurricanes Pauline and Rick destroyed it all. When the storms passed, nothing remained but red mangrove trunks jutting from the water like stripped bones. Initial cleanup took the residents three weeks of labor by hand. Then came a decision: rather than wait decades for nature to recover on its own, they would accelerate the process. Over 30,000 mangroves have been replanted since then, mostly red and white varieties, along with ferns, royal palms, mahogany, parota, and ceiba trees. Seeds were collected from whatever healthy plants survived, nurtured in small greenhouses, and transplanted to the lagoon area once large enough. The recovery has been remarkable. Flora and fauna have returned in force, and the replanted mangroves now form a dense, living canopy where devastation once stood.

Ecotourism in La Ventanilla grew out of necessity. When Mexico banned the sea turtle and crocodile trade, the communities along this coast lost their primary livelihoods overnight. Organizations like Ecosolar stepped in during the 1990s to help ten local families reimagine their relationship with the wildlife they had once hunted. The result was Servicio Ecoturisticos de La Ventanilla, a cooperative that runs guided tours of the lagoon by land and canoe. On Uma Island, in the middle of the lagoon, visitors find a mangrove reforestation greenhouse, a nursery where baby crocodiles are hatched and raised for eventual release, and a small restaurant under a palapa roof. A second cooperative, Lagarto Real, offers its own boat tours that skip the island for visitors who prefer to see the lagoon without encountering caged animals. During nesting season, hundreds of sea turtles crawl ashore to lay eggs on the beach at night. Community volunteers patrol the sand, helping exhausted turtles up the steep sections, then carefully gathering eggs to rebury them in a monitored area safe from predators. About three months later, the baby turtles are released into the ocean - a moment visitors can witness and participate in.

La Ventanilla has resisted the gravitational pull of resort development that has transformed other stretches of the Oaxacan coast. There are camping facilities and basic cabins - some with air conditioning - but nothing resembling a tourist hotel. No lifeguards patrol the beach, where the surf runs rough. Horseback riding along the sand is available, and locals will guide visitors west along the beach to another mangrove area for a small fee. The village remains what it has been since the coconut plantation days: a handful of families living at the end of a road, making their living from a landscape they have chosen to protect rather than develop. That choice - conservation over commerce, community over tourism infrastructure - is what makes La Ventanilla unusual. It is not a nature reserve managed by a distant government agency. It is a village that looked at its lagoon, its turtles, its crocodiles, and its mangroves and decided that keeping them alive was both the right thing to do and the only viable way forward.