Trinidad Leatherback Sea Turtle Watch: A Night on Grande Riviere Beach

The beach at Grande Riviere is dark in the way that beaches are only dark far from cities—the horizon barely distinguishable from the sea, the sand a pale grey path between invisible waters and invisible forest. Nadia Ramrattan, lead warden for the Grande Riviere Nature Tour Guide Association, walks without a torch along the surf line, reading the beach in ways that have nothing to do with vision. The sand is marked at intervals by depressions—crawl tracks, made when a leatherback came ashore earlier in the night—and she traces each one to its endpoint: a nest mound, or a return track heading back to the water, or occasionally an abandoned excavation where the female decided the site was unsuitable and retreated.

Grande Riviere, on Trinidad’s northeastern coast, receives one of the highest concentrations of nesting leatherback sea turtles in the world. Between March and August, up to 500 females per night may come ashore on this half-kilometer beach to lay eggs—an aggregation that represents a significant portion of the Atlantic leatherback population. The turtles can weigh over 900 kilograms and travel thousands of kilometers from their feeding grounds in the cold, jellyfish-rich waters off Newfoundland and Nova Scotia to lay here, returning to the beach where they themselves hatched, drawn by mechanisms that are still not fully understood.

Nadia has been working the nesting season for fourteen years, initially as a volunteer, now as the association’s lead warden, overseeing a team of twelve guides and coordinating with the University of the West Indies turtle monitoring program. She knows individual females by their tagged identification numbers and, increasingly, by their personal characteristics—the shape of a particular scar, the pattern of pink dermal markings on the carapace—and refers to returning veterans by names she has assigned them over successive seasons.

At 11 PM a turtle is seen emerging from the surf—first the enormous dark shape in the shallows, then the deliberate crawl up the beach, propelled by the same front flippers that, in the water, power extraordinary migrations. The leatherback’s carapace is not hard like other sea turtles’ but cartilaginous, flexible, covered in a smooth rubbery skin that gives the animal its name and its distinctive appearance. This one, by Nadia’s rough estimate, is between 400 and 500 kilograms. She instructs the small group of permitted visitors to remain still and allow the turtle to clear the surf zone.

The nesting process takes between forty-five minutes and an hour. The female excavates a body pit with her front flippers—a wide depression in which she settles to give herself stability—then digs the actual egg chamber with her rear flippers, alternating in precise scooping motions that descend to about half a meter. The excavation is methodical and patient; she does not stop, does not appear to hurry. Nadia measures the distance from the nest to the high-tide line and records it in a waterproof notebook. Too close and the nest risks inundation. The females instinctively select appropriate sites, but monitoring allows for emergency relocation of nests laid at risk zones.

When the eggs begin to drop—tennis-ball sized, slightly soft-shelled, in clutches averaging eighty to ninety eggs—Nadia’s assistant crouches at the chamber edge with a headlamp and a clipboard, counting. The females are not disturbed by observers during egg-laying; they enter a state of focused physiological commitment from which external stimuli do not easily divert them. It is this window that permits researchers to take measurements, attach or check tags, and collect tissue samples.

The leatherback has been nesting on this beach, and beaches like it, since before the Caribbean was called the Caribbean. The oldest leatherback fossils date to 110 million years ago, making the species roughly contemporary with the dinosaurs. The creatures now on Grande Riviere beach are, in some meaningful biological sense, an unbroken chain extending that far back. Nadia finds this less abstract than it might sound—she has watched 500-kilogram animals haul themselves across this sand for fourteen years, and the physicality of their presence makes the timeframe feel real in a way that reading about it does not.

The threats are multiple and well-documented: poaching of eggs and adults (significantly reduced on Grande Riviere since the tour association created economic incentives for conservation), entanglement in longline fishing gear at sea, plastic ingestion (leatherbacks mistake plastic bags for jellyfish), and climate change, which is shifting beach temperatures in ways that affect the sex determination of hatchlings and may alter nesting phenology. Nadia speaks about these pressures without despair but without minimization. The population at Grande Riviere is doing well by some metrics and poorly by others, and she holds that ambiguity without resolving it.

The female covers her nest with rear flippers and then disperses the evidence—spreading and flinging sand in a wide radius—before turning toward the ocean. The return journey is faster than the arrival, pulled by gravity and the proximity of water. At the surf line she pauses for a moment—the last moment of stillness—then a wave breaks over her carapace and she is gone, back into a sea she will cross at least twice more before the season ends.

Nadia marks the nest location with a wooden stake and GPS coordinates. Sixty days from now, the eggs will hatch, and the hatchlings—if the nest survives—will scramble toward the surf in a process that is simultaneously reliable and precarious. She will be here for that, too. She will be here every night until August. She goes to the next nest mound and kneels in the sand, continuing her work in the dark.

More Travel Guides