Trinidad is home to giants. Or at least, they are born here. And although they wander the oceans for most of their lives, they return when it is time for the next stage of their lineage to be created. By giants, I mean, of course, leatherback turtles: the largest of all sea turtles, essential to marine ecosystems across the globe. Wherever these nomads travel, they will return to the same nesting sites for generations, a phenomenon called “natal homing”. Across the world, there are two places known to have the largest nesting locations for these unique creatures—Gabon, Africa; and Grande Riviere, Trinidad and Tobago.
Trinidad is home to giants. Or at least, they are born here. And although they wander the oceans for most of their lives, they return when it is time for the next stage of their lineage to be created. By giants, I mean, of course, leatherback turtles: the largest of all sea turtles, essential to marine ecosystems across the globe. Wherever these nomads travel, they will return to the same nesting sites for generations, a phenomenon called “natal homing”. Across the world, there are two places known to have the largest nesting locations for these unique creatures - Gabon, Africa; and Grande Riviere, Trinidad and Tobago.
Over decades, the now endangered species has been seen in declining numbers, and a team of researchers at UWI St Augustine, led by Department of Geography Senior Lecturer Dr Junior Darsan, has been studying the world-renowned nesting site to collect data on what makes it so special—and to find out how we can better support the welfare of these marine megafauna and the human communities that exist alongside them.
“Leatherbacks used to be very populous,” says Christopher Alexis, a PhD student working under Dr Darsan at Grande Riviere. “Sixty, 70 years ago, we had thousands upon thousands. Now we really don't have that many.”
There are a host of reasons for this, almost all thanks to humans, he explains. “Overfishing, poaching, harvesting... habitat deterioration.”
But the genesis of this project was one specific incident that put Trinidad on the face of global news. “Leatherback Turtles: Trinidad 'regret' over loss of eggs”, read the headline of the 2012 BBC article. The piece said, “Officials in Trinidad and Tobago have expressed regret over the crushing of thousands of leatherback turtle eggs and hatchlings.”
An entire generation, gone in an instant.
Christopher Alexis, a PhD student in the Department of Geography and research officer at the Institute of Marine Affairs
At the time, Dr Darsan was employed at the Institute of Marine Affairs.
“Back in 2012, while working there, there was a major river flooding event in Grande Riviere,” he recalls. “The beach berm impeded the river’s normal outflow and it carved out a new river channel, trying to drain into the sea.”
A new body of water now blocked access to the beach in the middle of nesting season, affecting both the humans that lived and worked nearby, and destroying nests in the process. The Ministry of Works hurriedly dispatched heavy machinery in an attempt to re-route the river, digging up the beach in the process and further destroying an estimated 20,000 eggs. In the aftermath, Dr Darsan was part of the meetings held to try and salvage what had become an international incident.
“That's where it started,” he says. “We had several objectives from the 2012 event that led to the creation of this project.”
But how could we turn this bungled eco-response into an opportunity to learn? There was no way to undo what had already been done, but we could ensure that it didn't happen again. For a site of such global importance, there was very little data available at the time, and gathering that data was the first step.
It wasn't just about the turtles. The team wanted to understand how people use the beach - the human puzzle piece of the environmental picture. This is where Dr Sayyida Ali came in. With a background in geography and environmental natural resource management, this project would become the backbone of her PhD research, focussing on the people of Grande Riviere: the communities that live there and the visitors that pass through during turtle nesting season.
“So, my study looked at the socioeconomics of Grande Riviere itself,” she says. “How many tourists are coming up there, how many residents of Grande Riviere are employed or involved in the tourism activities going on up there, what are the sources of income for the community? It took a very community-based coastal resource management perspective to ask the residents, 'How does this impact your life, and how would you want to be more involved if this has to grow? If you could get more involved in the sector, how would you want that to go?’”
For the team, considering the needs and wishes of the community was vital to the work they were doing. They needed to be willing to have a two-way exchange of information—to learn from the residents as well as share knowledge.
Dr Darsan says, “We had some lessons to learn, and they can learn from us in terms of how we can have a more community-based approach to management.”
But humans are only part of the ecosystem. The research team needed to understand the broader scope of the natural system itself—mapping the flows in the bay, the way sediments moved around the area over time, and the nature of the elements that have come together to create such an opportune space for turtles to nest. This was the crux of Christopher Alexis's work.
“He paid a lot of attention to the beach habitat itself, to the sediment,” says Dr Darsan. “What's the relationship with the sediment and the successful nesting? What makes Grande Riviere so unique?”
Alexis's PhD work is on coastal geomorphology, which looks at how the physical features of the coast have been formed and how they change over time.
“The research basically centres on trying to identify the variables or the conditions necessary for the turtles to nest,” says Alexis. “And that has never been done at all. There were some anecdotal descriptions, but no empirical evidence.”
His hope is that the work can be used to help improve leatherback turtle numbers, not just in Grande Riviere but around the world. And while saving the species has its own intrinsic value, there is also the wider impact that these underwater giants have on the marine world around them—and our world by extension.
“Leatherbacks are important because they basically regulate global fisheries,” says Alexis. “They keep the balance - and if leatherbacks disappear, then the food web would collapse on itself.”
Dr Junior Darsan, lead researcher and lecturer in the Department of Geography within UWI St Augustine’s Faculty of Food and Agriculture
As Caribbean people, through the happenstance of where we were born, we are the custodians of natural ecosystems that are not only unlike anything else on earth, but also affect everything else on earth.
“Grande Riviere is a site of international importance,” Dr Darsan underscores. “I don't even think the general public realises that. These creatures are huge, and year after year, they find themselves back to our shores, however nature designed it, to propagate the population or to maintain the species. This is a big deal, and we're not making a big enough deal of it.”
My mind harkens back to visiting Grande Riviere as a child with not much understanding of its global importance, but a deep feeling that I was witnessing something magical as I saw baby hatchlings crawl their way through the sand, bypassing the hungry sentries of black corbeaux and the detritus of already opened shells to slip into the foamy waves where a host of other misfortunes could befall those tiny, fragile things. And yet, they bravely make their way out, and one day find their way back home to us again.
For more information on research projects and programmes of study at UWI St Augustine’s Department of Geography, visit https://sta.uwi.edu/ffa/geography/.