New Collaboration to Tag Juvenile Leatherbacks in Thailand

In early April, Upwell partnered with the Phuket Marine Biological Center (PMBC) in Thailand to tag and release 11 juvenile leatherbacks, each around 1-year old. This release was the latest collaboration in Upwell’s Lost Years Initiative, an international effort to collect data on the movements and behaviors of early stage juvenile turtles. Since 2021, Upwell has deployed various models of Lotek micro-satellite tags on 224 juvenile turtles in collaboration with institutions engaged in sea turtle conservation around the world, including Florida Atlantic University (FAU) Marine Lab, Okeanos Institute of the University of Azores, Two Oceans Aquarium, the Cayman Turtle Centre, and now, the PMBC.

Photo by Dang Chankit Chamnivikaipong

Photo by Dang Chankit Chamnivikaipong

The release of leatherbacks with PMBC is significant, as it was the first time juvenile turtles from this endangered Thailand nesting subpopulation have been equipped with satellite tags.

Pinsak Suraswadi, Director-General of Thailand's Department of Marine and Coastal Resources explains that the program was launched to nurse the weak baby leatherbacks that did not successfully make their way into the ocean after hatching. The PMBC’s captive rearing success was detailed in their 2023 publication “First successful head-start program of leatherback sea turtles (Dermochelys coriacea) in Thailand and proposed dietary strategy”.

When Upwell Executive Director Dr. George Shillinger read this groundbreaking research, he reached out to the PMBC about opportunities for collaboration. The 1-year old leatherbacks offered a unique opportunity to learn more about the West Pacific leatherback rehabilitation efforts and juvenile habitat use of the area. Upwell’s Volunteer Liaison Elle Onsathit worked tirelessly with Dr. Shillinger and the PMBC team to aid with translations and guide agreements that laid the groundwork for a fruitful partnership. 

In early April Dr. Schillinger traveled to Phuket for the tagging and release of the leatherbacks. To amplify the partnership, Dr. Shillinger brought colleagues from other collaborators on the Lost Years Initiative, Florida Atlantic University Marinelab and The Cayman Turtle Center. Both of these institutions have sea turtle captive rearing programs and their visit to the PMBC was an opportunity to learn and exchange knowledge around captive rearing practices. When it came time to tag the turtles, FAU’s Dr. Jeanette Wyneken provided expertise on the specialized tag attachment techniques she developed.

Unfortunately, the carapace of the 1-year old leatherbacks posed unexpected challenges as it was much smoother and more waxy than the scaly carapaces of the 3-month old turtles for which Dr. Wyneken had developed the techniques. Nevertheless, the team was able to deploy all eleven tags on turtles which were then released in two different locations off the southwest coast of Thailand. 

Photo by Dang Chankit Chamnivikaipong

"I'm excited to know more about whether our effort in nurturing the leatherback sea turtles for a year proves fruitful or not," said Senior Fishery Biologist, Hirun Kanghae. "If they survive, it answers everything about the conservation and population restoration of the leatherback sea turtles in the best way possible," he said.

The tags have already collected valuable data which Upwell analyzes and interprets with partners at Mercator Ocean International. While attachment failure did seem to impact some of the tags, others transmitted to reveal movement and dive behavior. Some turtles stayed close to the release site, while others traveled west towards the Andaman Islands and seemed to circle in an oceanic gyre, and another traveled south towards Sumatra.

Photo by Dang Chankit Chamnivikaipong

Upwell Executive Director Dr. George Shillinger commented, “As our Lost Years Initiative grows with new collaborators, our understanding of where and how juvenile turtles from different populations of different species are spending their time at sea grows accordingly. So too, does our understanding about how these populations may be differentially exposed to various human related impacts within the highly dynamic marine environment. This information is critical to informing our efforts to mitigate threats to vulnerable and imperiled sea turtle populations and to advancing recovery measures and targeted conservation efforts.”