- Plan Your Trip
- Research & Conservation
In honour of World Animal Day, Cayman Turtle Conservation & Education Centre released two Head-started juvenile green sea turtles into the Caribbean Sea on Monday 4th October as part of our ongoing sea turtle conservation mandate.
Aside from being a national symbol of the Cayman Islands, Green sea turtles have an important environmental role as a ‘keystone’ species in the marine ecosystem and as one of the ocean’s few large marine herbivores, maintaining coral reefs and seagrass beds by grazing on algae that might overgrow our reefs and by mowing the coastal seagrass in our Sounds to keep them healthy. This helps not just sea turtles but also other breeding marine life such as conch, lobsters, and reef fish, thereby also benefitting our local culture and economy through fishing, diving, etc.
These two juvenile green turtles, affectionately named “Speedy” and “Sweetie” by Peter Milburn, one of their caretakers, began their lives as eggs laid by one of CTCEC’s breeding female turtles. They were hatched and raised together with their many brothers and sisters under the care of our veterinarians and animal care team until approximately 2 years old and weighing an average of 30lb (13.6kg). After undergoing a thorough pre-release quarantine and health check protocol, the two juvenile turtles were ready to be released into the wild.
Once these CTCEC-raised turtles are released into the wild our job is complete! They are now considered wild sea turtles and a Protected species under the Cayman Islands National Conservation Law, falling under the jurisdiction of the CI Department of Environment.
This will be the first time that these turtles, raised under human care, will experience the wide blue ocean. But never fear! Sea turtles, like most reptiles, are instinctual learners. Through centuries of evolution, all they need to know to survive is already imprinted in their reptile brain, which will trigger once they are out in the wild. Within a day or two of being out in the ocean, they will start feeding and behaving like wild turtles.
As part of that transition to the wild, it is not unusual to see newly released turtles swimming in what may seem an erratic manner close to shore, at times maybe even coming out on the sand for brief periods. We advise the public not to approach or interfere with the turtles at this stage since this is just part of their orientation process as they familiarise themselves with their new home and set their “landmarks” for finding their way back as breeding adults.
At this age, we are still unable to tell the gender of our turtles through external features. At 5 – 7 years old, male sea turtles will grow their tails longer than their back flippers while female tails remain short. Egg incubation temperature also influences the sex of the hatchling turtles. In the CTCEC Hatchery, 82*F is considered a mid-range temperature yielding an almost 50:50 ratio of males to females when they hatch after 2 months. Eggs incubated warmer than 82*F tend to produce more females, while cooler temperatures mean more males, or as we say at CTCEC: “Hot chicks, cool guys!”.
“Head-starting” means growing the release turtle to a size that significantly reduces the risk of predation. Hatchling turtles have many predators due to their small size and softer shells, but at this stage, the only potential predators of our Head-started turtles would be large sharks and poachers. Even though we have helped to give our release turtles the best chance to survive most of the natural threats they may encounter in the wild, they still face a significant risk from man-made hazards such as marine pollution, especially plastic pollution. To address this issue, for some years now CTCEC has been preaching our “3 Plastics” mantra, encouraging the public to do their part to reduce plastic pollution and protect our sea turtles and other marine life by picking up (at least) 3 pieces of plastic every day, and encouraging others to do the same!
These released turtles each have an identification PIT tag embedded in the shoulder, just like the microchip your veterinarian will give to your pet cat or dog. The tag will stay with the turtle for its whole life. This is not a satellite tag that can be tracked online, but if a researcher encounters these turtles, they can use a pit tag reader to scan the turtle and retrieve the individual identification number that can trace them back to our Centre. In this way we know that our released turtles over the years have returned to Grand Cayman as adults to breed and have also been recorded in other parts of the Caribbean.
A multinational 2-year study funded by the Darwin Plus Initiative examined the impact of CTCEC’s turtle releases on Cayman’s wild sea turtle population over the past 50-plus years. The study was concluded in 2018, and the results have shown that 90% of Grand Cayman’s wild nesting green sea turtles have DNA that traces back to the turtles of CTCEC’s Breeder Herd!
Every released turtle is allowed to crawl into the ocean on its own. Some just rush right in, while others may sit on the sand for several minutes. This is part of the imprinting process where the turtle sets its internal “GPS” so it knows that this is home, and approximately 20 years later it will return to Grand Cayman to crawl out somewhere on this beach (if it is a female) and lay its own eggs. True to their names, “Speedy” scrambled straight into the water while “Sweetie” took his/her own sweet time getting in!