(CMR) Sea turtles in the Cayman Islands are recovering from the brink of local extinction, a study carried out by the Cayman Islands Department of Environment and the University of Exeter has found.
The study which monitored turtles in Cayman from 1998-2019 showed loggerhead and green turtle nest numbers increased dramatically, though hawksbill turtle nest numbers remain low.
According to an article by Exeter University, in the first counts in 1998-99, just 39 sea turtle nests were found in total on the three islands. By 2019, the figure was 675.
Captive breeding of green turtles and inactivity of a traditional turtle fishery due to the tightening of restrictions in 2008 is believed to have contributed to this. However, populations remain far below historical levels and still face threats, including illegal hunting.
“Our findings demonstrate a remarkable recovery for sea turtle populations that were once thought to be locally extinct,” said Dr. Janice Blumenthal, of the Cayman Islands Department of Environment.
Dr. Blumenthal said a combination of factors is thought to have led to this success.
“It is likely that a captive breeding operation by the Cayman Turtle Farm (now the Cayman Turtle Centre) drove the increase in Grand Cayman’s green turtle population in the early years of monitoring. For loggerhead turtles, the most important factor was the restrictions placed on the legal turtle fishery in 2008,” Blumenthal added.
Dr. Jane Hardwick, also of the Cayman Islands Department of Environment, said, “For both species, the recovery was assisted by protection efforts by the Cayman Islands Department of Environment on nesting beaches, including patrols by conservation officers to reduce illegal hunting.”
However, illegal hunting continues to be an ongoing issue, with a minimum of 24 turtles taken from 2015-19, many of which were nesting females, Hardwick said.
“Artificial lighting on nesting beaches, which can direct hatchlings away from the sea, increased over the period of our study. Additionally, as highly migratory endangered species, sea turtles are influenced by threats and conservation efforts outside of the Cayman Islands, showing a need for international co-operation in sea turtle management,” she stated.
The Cayman Islands had among the world’s largest sea turtle nesting populations, with turtles numbering in the millions. By the early 1800s, the populations had collapsed due to human overexploitation.
Despite reaching critically low levels, nesting populations of green and loggerhead turtles have recovered significantly; however, hawksbill turtle nest numbers have not increased in tandem with loggerhead and green turtles – with a maximum of 13 hawksbill nests recorded in a single monitoring season.
Cayman Islands authorities' efforts to protect the country's turtles. includes “turtle-friendly lighting” initiatives and a greater level of habitat protection for key areas, proposed under the National Conservation Law of the Cayman Islands.
Professor Brendan Godley, of the University of Exeter, said: “I was fortunate to have been involved in establishing the turtle monitoring program with the Department of Environment in the Cayman Islands back in 1998, and it is fantastic to see how protection and awareness has resulted in an increase in nesting turtles.
“The wonderful team and leadership of the Department of Environment have been instrumental in driving the monitoring and conservation.”
Department of Environment Director Gina Ebanks-Petrie said: “We are extremely grateful to the many volunteers, interns, property owners, businesses, organizations, and members of the public who have assisted with sea turtle conservation efforts over the past two decades.
“Sea turtles are a national symbol of the Cayman Islands, and our community has come together to demonstrate our commitment to their protection. This research gives us essential information for strategically targeted management efforts to secure the future survival of these populations.”