Known as Turtuga blanku in Papiamentu, the Green turtle (Chelonia mydas) is one of Bonaire’s more common species of sea turtles, along with the Hawksbill turtle (Eretmochelys imbricata). The Green turtle has a smooth edge to its shell (or carapace) and a rounded mouth, while the Hawksbill has a beaked mouth and a jagged edge to its shell. Green turtles nest on Bonaire’s sandy beaches and adults forage in coral reef areas, mangroves and seagrass beds. This large sea turtle is named for the green color of its body fat. Its carapace (shell) is olive and black colored with a teardrop shape. Adults live on a diet of seagrass and algae, although young Green Turtles also eat invertebrates such as crabs, shrimp and jellyfish. Green turtles typically stay underwater for 5 to 10 minutes when they are actively feeding, but can stay under for 2 to 3 hours when resting! They don’t need to come up for air during that time because their muscles and blood store large quantities of oxygen; their heart rate also drastically slows down to conserve as much oxygen as possible.
A number of monitoring projects have taken place to better understand the life cycles and migratory routes of this globally endangered species. Like other sea turtles, Green Turtles migrate vast distances between their nesting and foraging grounds. The Dutch Caribbean Nature Alliance collaborated with Stenapa St Eustatius and the St. Maarten Nature Foundation to track the migration route of both green and hawksbill turtles found on St. Eustatius and St. Maarten between 2006 and 2008. They founds that each of the four turtles they tracked travelled in a different direction—one went to the Dominican Republic, one to St Bartholomew, one to St Kitts and Nevis, and one stayed in St. Eustatius.
The IUCN Red List lists the Green turtle as endangered due human activities such as intentional egg harvest, contamination of or development on coastal habitats, incidental bycatch and degradation of nesting beaches. The local NGO S Sea Turtle Conservation Bonaire works to monitor, research and protect our turtles. We now know that female Green Turtles nest on Bonaire’s beaches at intervals of 2 to 3 years, and that adults are rarely seen outside the breeding season. Juveniles, however, are observed foraging year round in the waters around Bonaire. Through DNA analyses, it was found that these sea turtles come from other parts of the Caribbean and the South Atlantic. Some Green Turtles were found to come as far away as West Africa. They found that Green turtles in Lac Bay on Bonaire have much higher growth rates than in other parts of the Caribbean- demonstrating the importance of conserving seagrass and mangrove habitats in order to protect these turtles.