Tracking teen turtles: our research in the Turks and Caicos Islands

For more than a decade we’ve been involved in some fascinating research which has tracked the migratory habits of teenage green turtles. The work focuses on a Marine Protected Area (MPA) in the Turks and Caicos Islands, the results of which we’re pleased to share in a new paper.

The study has found that the tracked teenage green turtles will stay within the MPA whilst they are growing, but as they near maturity will migrate hundreds of miles across the Caribbean to most likely search out adult feeding grounds.

Between 2002 and 2017, as part of a research team, we worked alongside local fishermen to flipper tag 623 green turtles, also fitting 16 of the larger teenage turtles with satellite transmitter tags on the top of their shells. Upon release, each turtle was given a name, with turtles Dave and Gilbert being named after our expert fishermen we worked with.

TCI Turtle Tracking

The tagged turtles were released, where they were captured, on remote and pristine seagrass beds within the North, Middle, and East Caicos Nature Reserve MPA.

Four of the 16 satellite-tagged turtles migrated away from the Turks and Caicos Islands (TCI), three of these having spent months after release within the MPA, while one turtle migrated away just 13 days after release. Two of the migrating turtles, including Dave, headed west to Cuba, Gilbert headed north to South-East USA and the high seas, and another headed south to Central America. The latter turtle, named Karman after the niece of a team member, eventually settled at feeding grounds on the Colombia coast some 900 miles from the Turks and Caicos Islands having swam through the territorial waters of eight Caribbean countries. It’s most likely this was Karman’s initial voyage to find suitable adult feeding grounds, because she swam back and forth along the Central American coastline before settling at a site in Colombia’s inshore waters.

Four of the flipper-tagged turtles were captured years after release by fishermen in Nicaragua’s waters, and another was caught in Venezuela’s coastal waters.

Green turtle - TCI Tracking Project

The survival of teenage and adult turtles is critical to supporting population recovery. While we have a relatively good understanding of female adult turtles, that come to shore every few years to nest and so are easier to study, very little is known about the lives of teenage turtles which spend all their time at sea. We focused our satellite tagging study on teenage green turtles to learn more about their behaviours and worked closely with expert turtle fishers who gave us unique access to these enigmatic animals.

As part of the Turks and Caicos Islands Turtle Project, the research team worked with local fishing communities to bring in new conservation measures that have resulted in teenage and adult turtles being protected in TCI waters.

This research shows just how important this MPA is for green turtle populations across the Caribbean region. The turtles are feeding and growing up on the seagrass beds at this one, relatively small, site for many years, showing why resources should be invested in protecting these wild, pristine places. It’s vital that these habitats remain for years to come in order to support future generations of green turtles.

The paper, entitled “Spatial Ecology of Sub-Adult Green Turtles in Coastal Waters of the Turks and Caicos Islands: Implications for Conservation Management” is an open access article and can be accessed here: https://doi.org/10.3389/fmars.2020.00690