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The Bermuda Turtle Project was initiated in 1968 by CCC Board member Dr. H. Clay Frick in collaboration with the Bermuda Department of Agriculture, Parks and Fisheries and with Bermudian turtle fishermen. Building on traditional sea turtle capture methods used in Bermuda, Dr. Frick developed a highly efficient method of capturing juvenile turtles on grass flats with a long encircling net tended by snorkelers. This early research showed that the smallest green turtles were about 22 cm in shell (carapace) length and the largest about 80 cm. Recaptures of tagged turtles indicated that juvenile greens in Bermuda were resident in a local area and, if moved to another location, were able to return “home”efficiently.

In 1990, CCC Research Associates, Drs. Anne and Peter Meylan (of Florida Department of Environmental Protection and Eckerd College, respectively) joined the project at Dr. Frick’s request to investigate whether any of the Bermuda green turtles were sexually mature. Using laparoscopy (internal examination of the gonads with a special scope), a large sample of turtles was examined and all individuals were found to be immature. Subsequent research corroborated the hypothesis that Bermuda served as a “developmental habitat” — a place where immature turtles occur without the presence of adults. Because of Bermuda’s isolation from other turtle populations (it lies 960 km southeast of Cape Hatteras, North Carolina) and the complete legal protection extended to green turtles since 1978, the island represents a valuable laboratory for studying the biology of this poorly known life stage.

In 1992, Dr. Frick retired from the project and it became a cooperative effort of the CCC and the Bermuda Aquarium Museum and Zoo. Jennifer Gray, Head Aquarist, became project coordinator and Drs. Anne and Peter Meylan became the project's scientific directors. Since 1992, sampling has been extended to a larger number of sites, and has been conducted during all months of the year to establish the seasonality of occurrence of the turtles. Contrary to local lore, it was determined that green turtles are resident in Bermuda throughout the year. Many individuals have been recaptured several times, providing valuable data on growth rates, residence times, and site fidelity. The longest recapture interval of a tagged turtle in Bermuda has been 12 years, but given their slow growth rates, and the size range that is seen at Bermuda, it can be inferred that they may stay there for decades.

A Geographic Information System (GIS) has been developed for the project to analyze spatial patterns of occurrence of the turtles. Information such as water depth, water temperature, bottom type (grass, reef, sand), and ocean currents can be overlaid on the turtle capture positions. A dissertation research project by Marjo Vierros in collaboration with the Bermuda Turtle Project has examined the utility of remote sensing tools for distinguishing good turtle foraging areas. Detailed ecological sampling by Marjo at the project’s regular sampling locations promises to advance our knowledge of some of the characteristics that define green turtle foraging areas.

Although there was a nesting colony of green turtles in Bermuda during the Colonial Period, it has been extinct for at least 80 years. A recently completed genetic survey carried out as part of the Bermuda Turtle Project suggests that the green turtles that grow up in Bermuda come from several nesting beaches, including Florida, Costa Rica and northern South America. We have also learned more about where green turtles go after leaving Bermuda. Turtles that were tagged as part of this project have been recaptured in Cuba, the Dominican Republic, Nicaragua, the Grenadines, and Panama.

We have recently begun to explore the routes by which large immature turtles travel to the next habitat in their life cycle. In 1996, a 72-cm green was outfitted with a satellite transmitter with hopes that it would depart Bermuda waters, and that its route could be traced. Seventy centimeters is about the size of most of the Bermuda green turtles that have been recaptured in foreign waters. Contact with the turtle was maintained for a remarkably long time (15 months), but she never left the waters of Bermuda. Because of the error inherent in the system, it is impossible to say whether the short-distance movements indicated by the points represent real travel; it is possible that the turtle never left its original capture site. Although the experiment did not yield data on migration, hundreds of transmissions were received giving valuable information on diving and surfacing behavior and on water temperature. Research plans for 1998 include outfitting three or more subadult green turtles with satellite transmitters in hopes that an open ocean voyage can be monitored. The 1996/97 satellite tracking work was sponsored in part by the U.S. Fish and Wildlife Service.