On the sandy shores of Grande Riviere beach, Trinidad, a phenomenon known as coastal squeeze threatens the survival of leatherback turtles. Coastal squeeze occurs when a beach is sandwiched between rising sea levels on one side, and coastal development on the other.
This leaves no chance for the beach to migrate inland, as would occur naturally following sea level rise, had there been no buildings blocking its path. Grande Riviere beach is one of the most important nesting sites for leatherback turtles in the world: should it ever disappear completely, that would mean a loss of over 30 thousand turtle nests—every year!
A shrinking coastline
A kilometer-long stretch of sand leading to a headland covered by thick forest growth characterizes the Grande Riviere beach. Anecdotal evidence obtained by villagers confirms that the western end of the beach was “considerably wider thirty years ago”. The shrinking of sandy beaches by coastal squeeze is one of the most severe threats they face, and this is only exacerbated by the rising sea levels.
The average global sea level rise of 1.8mm a year—which may not seem like much now—will “decrease nesting habitats in the longer term”, says the International Union for the Conservation of Nature (IUCN).
According to a 2016 study led by University of the West Indies researcher Junior Darsan, optimal turtle nesting locations need “sufficient space above the high tide line for nesting.” With less space on the beach, which is frequently visited by these giant turtles, a more short-term problem emerges: the overcrowding of nests.
According to a 2016 study led by University of the West Indies researcher Junior Darsan, optimal turtle nesting locations need “sufficient space above the high tide line for nesting.” With less space on the beach, which is frequently visited by these giant turtles, a more short-term problem emerges: the overcrowding of nests.
The spatial dilemma
“What that would have created over time is a scenario where turtles begin to dig up each other’s nests,” says Len Peters, Chairman of the Grande Riviere Nature Tour Guide Association (GRNTGA). “Just imagine, a beach only one kilometre [long] and you can encounter over the course of one night as many as 500 leatherbacks.”
Peters and his team are responsible for monitoring and ensuring the safety of leatherback turtles on the Grande Riviere beach. To prevent turtles from unknowingly destroying each other’s eggs, the GRNTGA carefully dug up certain nests and relocated them to “hatcheries” where the eggs could incubate in safety. This goal is to prevent these nests from being damaged by other turtles ready to lay their eggs.
Are the buildings really the problem?
The presence of buildings near the coast prevent the beach from naturally extending backwards to protect itself from the rising sea levels. According to the 2016 study, infrastructural development should never have been allowed so close to the beach.
The buildings currently occupying the backshore are mainly for tourism: hotels, restaurants, and guest houses. Yet these remain crucial to the economy of the Grande Riviere community, as they provide a source of income for many of the locals.
“Grande Riviere tourism [is] based on turtles, that’s the main idea,” says a local named Ashton, who has been living on the beach for almost forty years. “A lot of villagers live on it, a lot of villagers are single parents coming along to do this work [with the turtles] now.”
It is villagers like Ashton who help to keep an eye on the hatchlings. Living in a house surrounded by coconut and breadfruit trees on the backshore, Ashton steps in whenever he sees baby turtles in danger from daytime predators. “I’ll take [the turtles], keep them all day long, and release them in the safety of the darkness, so definitely they have a better chance [of survival],” he says.
The obvious solution—removing the buildings—will potentially allow room for the beach to recede naturally as the sea encroaches further inland. Yet removing them would also displace locals who have been there for decades, protecting the turtles or adding to the local economy. It is easy to point fingers at the immediate issue here—the buildings on the backshore—but the global issue of rising sea levels remains at large. And who is to blame for that?
