Until recently, researchers were unable to conduct satellite tracking studies on juvenile turtles due to their small body sizes and immediate dispersal into the ocean, leaving this period of their lives enigmatic and often referred to as the “lost years.” A new study, “Pioneering insights into the diving behavior of early-stage sea turtles revealed by novel marine miniaturized satellite tags,” published in Scientific Reports in April 2026, provides the most comprehensive analysis to date of vertical diving behavior in early life stages of leatherback and loggerhead sea turtles.

Much of the current telemetry data collected by tagging hawksbills is from adult females, due to the fact that they are easiest to tag when they crawl up the beaches to nest. To expand our knowledge of small juvenile hawksbill movements, Upwell teamed up with ProTECTOR, Inc., an organization with the goal of advancing our understanding of sea turtle biology and ecology through research throughout the coasts of Honduras. In early July the collaborative team tagged eight juvenile hawksbills with micro-satellite tags. The turtles were then released just off of the northeast reef of the Bay Islands, with some making impressive journeys.

Last year in July, we deployed 10 micro-satellite tags on juvenile loggerheads in partnership with the Aquarium La Rochelle in France. Of this cohort, all of which are named after European scientists, the tags on turtles Archimede, Nicolas Copernic and Charles Darwin have continued to transmit for an astounding 312 days and counting (a new record)! As we prepare to release another set of turtles, we wanted to take a moment to reflect on some of the observations from this first deployment, and how they help us to take the next steps in our research.

Six months ago, Upwell and Two Oceans Aquarium deployed micro-satellite tags on 12 loggerhead turtles rehabilitated at the Turtle Conservation Centre. We watched their progress with many questions and hypotheses. While it will take far longer than six months to answer any of these questions fully, we made some fascinating observations that allow us to ask even more questions! 

Upwell Turtles, the Okinawa Churaumi Aquarium, and the Sea Turtle Ecology Lab (STEL) have launched a partnership to explore the migratory ecology of the early life stages of loggerhead sea turtles.

Upwell’s Executive Director, Dr. George Shillinger, recognized that the rehabilitated early-stage juveniles at the Aquarium La Rochelle CESTM were perfect candidates for Lotek microsatellite tags and invited CESTM to join Upwell’s Lost Years Initiative, kicking off the collaboration with the tagging of 10 juvenile loggerheads in late July. Over the past two months, the turtles have shown a range of behavior, including surprisingly deep dives for turtles of such a young age!

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.