CHS Blog

Cross Border Collaborations for the Majestic Leatherback

August 21, 2023
Amy Mui, PhD, Lecturer, Dalhousie University

I wanted to write this blog because I recently witnessed two magnificent things. One being the age-old process of enormous Leatherback (Dermochelys coriacea) mothers emerging from the surf and delicately sculpting nests for their eggs. The second being the successful collaboration between two conservation groups with similar goals but carried out in very different parts of the world (one in Canada, and one in Trinidad).

I am not a sea turtle expert, but my work uses satellite imagery and geospatial approaches in support of declining species conservation, so this adventure was right up my alley. I teach in the Environmental Science program at Dalhousie University, but you do not need to be a researcher or expert of any kind to join this excursion. I was graced with the company of twelve other intrepid travelers from Canada and the US and we quickly bonded over our intense love of turtles. We took a red-eye flight to Port of Spain, Trinidad, arriving in the intense heat of May. Our visit was timed with the peak of the Leatherback nesting period, which ranges from March to August. Our guide and unflappable leader was Kathleen Martin of the Canadian Sea Turtle Network (CSTN) based in Halifax, Nova Scotia. Aside from having a decades long history of active sea turtle research, policy consultation, advocacy, and community leadership, Kathleen was just a lovely person to spend time with and share stories with.

Our roughly nine-day excursion began with a day of training where we also met Suzan Lakhan-Baptiste, founder of Nature Seekers, the Trinidadian conservation group who were our hosts, gracious guides, and local knowledge holders. Suzan's story warrants an entire article to itself (one has already been written here), but I will sum it up by saying any person who can reshape a culture from turtle poaching to turtle protection, deserves the title of Mother of Turtles, for which she is lovingly known. Between Suzan and Kathleen, we became armed with knowledge of Leatherback biology, research, threats, and hands-on skills for how to tag, microchip, and measure nesting mothers.

Our purpose was to assist with nightly beach patrols, to process as many nesting turtles as possible, and to find the elusive females that were tagged up in the North Atlantic waters of Canada by the CSTN so satellite tags could be attached to their shells. The research in Trinidad is highly complementary to that conducted in Canadian waters. The CSTN places flipper tags on Leatherbacks found off the coast of Nova Scotia. If turtles marked in Canada are found nesting on a Trinidadian beach, then the goal is to outfit these "double observed" turtles with a satellite transmitter. These turtles with satellite tags provide vital information about their round-trip journey and possible threats along the way, which in-turn provides the basis for evidence-based conservation action.


Stepping foot onto Matura Beach at night during nesting season was a thrill even before we saw our first turtle. The warm wind blows as constantly as the stars shine from above, and the moon was so bright it seemed like someone turned off the lights when a moving cloud passed overhead. Mats of thick Sargassum, a macroalgae washed up from floating ocean mats, carpeted the beach. Due to the currents, trash can be found in almost equal density, but the community comes together annually to clean-up the beach ahead of nesting season. This is a feat that cannot be appreciated fully unless you have seen how much garbage washes up from far away destinations.

Armed with my red headlamp and accompanied by my equally excited nephew (turtle love runs in my family), we walked for what only felt like ten steps before we saw our first moving rock. No, it's a log. No, just a rock. Wait. Yup, that's a turtle.

Moonlight reflected off the leathery back of this female as she lumbered slowly up the beach. Unlike all other sea turtles, which are in the family Cheloniidae, Leatherbacks belong to their own family called Dermochelyidae. This species is the sole extant member of the scute-less sea turtles, their shells being covered instead with leathery skin. Even more fascinating is the structure of the shell beneath, which is comprised of thousands of small puzzle pieces (bony plates) connected by collagen fibres which give these giants flexibility when they dive. Seven longitudinal raised ridges further help to keep the shell intact when it is compressed at depths of over 1000 metres, deeper than any other sea turtle can dive.

Back on land, Leatherbacks are not very skittish, likely owing to the fact that they cannot react very quickly to anything given their large size and slow pace. This means that you can safely hunker down a few metres away as they decide whether this is the night to nest. Once a female starts flapping her fins and shuffling her body to make a depression in the sand (a process known as body pitting) it is safe to approach - for the turtle and human.

Looking into the eyes of a Leatherback is to look 150 million years back in time. Their faces are ancient, and their size remarkable (reaching almost 2 metres in carapace length). This female took in gulps of air as she moved her massive body onto the beach. This species can reach weights of over 1500 lbs (680 kg)! Leatherbacks also have a pineal or pink spot on top of their heads, which is used to sense changes in daylength and is unique amongst the sea turtles. Once she started digging a small hole with her hind flippers, it was almost a sure thing that she would nest. The movements of each flipper were like a ballet. Rhythmical, precise, delicate, and removing a surprisingly small amount of sand with each scoop that was then methodically patted down away from the growing hole. Despite their size, you could see how vulnerable these creatures are when on land. They have no defenses against poachers, nor do their nests. Everything they do is slow, and measured, and unchanged through time. Suzan spoke of a prior time when turtle harvesting was a part of local culture and Matura Beach was known as "a graveyard for Leatherbacks' with a stench of rotting flesh you could smell from far away." Fortunately, thanks to her tireless efforts and those of the community, Matura beach is now known for its turtle conservation efforts and proof that traditions can change for the better.

Now, surrounded by human turtle protectors and warriors, our female began laying her eggs. She entered into a trance and we could begin our work without disturbing her. We used a microchip reader to scan for an existing PIT tag and finding none, inserted one near her right shoulder. Finding no flipper tags, we clipped one onto each hind foot. This required straddling the turtle across her middle and leaning down to reach for the flap of skin between the foot and the tail. Others took the GPS readings, measured her carapace length and width, and noted any unique characteristics or injuries onto the record sheet - a process completed for each turtle.

Among the many things that I learned one fascinating fact stands out: Have you ever heard of spacer or yolkless eggs? These are miniature non-viable eggs whose purpose might be to support oxygen exchange (by promoting air circulation amongst the tightly packed eggs), regulate moisture in the nest, or prevent compaction by the sand. This nest had quite a few spacer eggs, but they are not counted as part of the clutch.

Our work done, we left our first female to finish patting down her nest and we broke out into smaller groups to better cover the 18 zones of Matura beach. I was ecstatic to see a turtle on night one. But my expectations were blown away by the ten more we saw that night. Followed by 15 turtles the next night, 13 the night after, and over 50 the night we visited Grand-Riviere beach - a unique location where turtles are packed into such a small beach that they nest on top of other nests, and each other it seemed! We were present on one of the nights when the turtles were being weighed at Matura (yes, weighed!). With care and precision this giant was gently harnessed then lifted. Turtles are in the air for only a short moment, and still being in a trance-like state after completing the nesting process, you can only wonder what they might be thinking. Then they are down again and ready to head back into the dark surf.

There is so much to say about those nights spent walking the beach. Each of our guides had their own unique personalities, tips and tricks, and ways that they whispered to the turtles they protected. The turtles themselves also had their own personalities. Some were indecisive, some made poor choices for nest sites, some were no nonsense and began nesting without hesitation, while others left meandering tracks about the beach before deciding just to head back into the surf. We never did find a Canadian turtle (a turtle previously tagged in Canadian waters, that is!) on this trip, but I am happy to report that they found one the week after we left, and she was given a fashionable satellite tag to accompany her on her way back to the North Atlantic where hopefully CSTN will encounter her again.

This collaboration between NatureSeekers and the CSTN began in 1999. Kathleen and her group regularly travel to Trinidad for monitoring and research efforts. Approximately 60% of Leatherbacks that feed in North Atlantic waters of eastern Canada nest on the beaches of this large island nation. The working relationship between these two groups is both highly professional and familial. Suzan's NatureSeekers is a family and community-oriented organization. At any time in the guest house, we would meet and hang out with the children of the beach patrollers. Many of them call Kathleen, 'Aunty Kathleen'. The travel extends in both directions with Trinidadian NatureSeekers also coming to Canada, specifically Halifax, to learn and train with the CSTN as they observe and tag sea turtles from boats as the turtles feed on abundant populations of jellyfish. In fact, I met up with two Trinidadian NatureSeekers, Rhema and Kyle, in late July that same summer and took them to Playdium (a giant arcade) to give them a taste of our video-game culture on a rainy maritime day. Rhema is the top turtle tagger with over 300 turtles tagged this season alone. Kyle is their technical expert who manages satellite tagging and drone flying among other duties (what a cool job description, eh!?). I can write so much about the other NatureSeekers and members of our CSTN group if time and space allowed. Likewise, there is so much to be said of the beauty of the natural sites we visited on our daytime excursions, the crafts that are made using repurposed materials pulled from the beach, the delicious food, and all the Trini slang we learned.

I feel fortunate to be a part of this international collaboration and family of turtle warriors (that's me on the bottom right). My own adventures with both of these groups are just beginning. I look forward to what's ahead in the same way that a Leatherback looks forward to eating a jellyfish...with gusto!

For anyone who is interested in learning more, click on the links for more information on CSTN and their Trinidad excursion as well as their partners in conservation the NatureSeekers (website upcoming) or feel free to email me directly !