Giant turtles, which were once feared for extinction, came to the fore with a picture that surprised scientists years later.
According to a report from the British press, The Guardian, a comprehensive study conducted in the Aldabra Atoll in Seychelles revealed that approximately 180 thousand giant turtles were roaming freely in the region. These creatures, which numbered less than a thousand due to intense exploitation in the 19th century, reached the highest population recorded for their species after decades of conservation efforts.
According to the research conducted by the Seychelles Islands Foundation (SIF) and the University of Exeter, the number of adult and semi-adult turtles in Aldabra Atoll is approaching 183 thousand. Thus, it turned out that the population of the species, which was once in danger of extinction, became stronger again after conservation programs.
'IT WAS UNDER A THOUSAND ONCE'
The results reached by scientists were obtained by analyzing five-year turtle counts carried out between 2018-2022. The research was the first major update since the population estimate of about 100,000 turtles has been widely used since the late 1990s.
The study, published in the scientific journal Ecology and Evolution, revealed that the adult and subadult turtle population remained relatively stable during the research period.
Aldabra Atoll is known as one of the two regions in the world where giant tortoises live in the wild. The other region, the Galapagos Islands, has a much smaller population.
'THEY BECOME BACK FROM THE VERGE OF DESTRUCTION'
Aldabra giant tortoises' growth to today's population did not occur spontaneously. In the 19th century, humans' intensive exploitation of animals reduced the number of species to less than a thousand. While the future of the species was in danger, conservation efforts were put into action in the region.
Aldabra Atoll was made a strictly protected nature area in 1981. A year later, in 1982, it was declared a UNESCO site. Conservation efforts spanning decades have paved the way for a transformation that is now considered one of the Indian Ocean's most significant conservation achievements.
Chief Executive Officer of the Seychelles Islands Foundation, Dr. Frauke Fleischer-Dogley stated that the more than 180 thousand giant tortoises roaming freely on the atoll show what long-term conservation efforts can achieve. Fleischer-Dogley stated that this development is pleasing for Seychelles, the world and everyone working for the protection of Aldabra.
WHY IS IT SO DIFFICULT TO COUNT THOUSANDS OF TURTLES?
Determining the number of giant tortoises on Aldabra was not an easy task for researchers. The dense vegetation on the atoll makes it difficult to see and count individual animals in some areas.
One of the co-authors of the study, Dr. Nancy Bunbury said the giant tortoise monitoring program in Aldabra is one of the longest-running efforts in the region. Bunbury stated that the researchers also included areas that they could not directly observe in the modelling.
This method produced one of the most reliable population estimates ever for Aldabra giant tortoises in the Seychelles. The researchers emphasized that the data obtained will form the basis for monitoring how the turtle population will change in the coming decades.
'NEW DANGEROUS AWAIT'
Although the resulting picture indicates a great success, scientists warn that the danger is not completely eliminated. Aldabra's changing climate poses an increasingly serious risk to the giant tortoises' future.
Longer and more frequent droughts are expected to reduce the food and shade areas turtles need. Sea level rise also threatens the lower parts of the atoll.
In addition, invasive animals that feed on turtle eggs and hatchlings continue to be a significant problem. Feral cats and black rats are among the major invasive mammals that threaten the future of the species.
Researchers estimate that planned removal of these invasive mammals could help the turtle population grow even further. It is stated that such a step could also make animals more resilient to the pressures of climate change in the future.
'THIS IS NOT THE END'
Postdoctoral researcher at the University of Exeter, Dr. Dave Hudson said that the results were pleasing for the turtles and demonstrated the success of the work carried out in the field.
However, according to Hudson, the population approaching 180 thousand does not mean that conservation efforts can end. On the contrary, this figure provides a starting point for tracking future changes.
Reminding that turtles face pressures caused by climate change, drought and invasive species, Hudson expressed that they hope that the data obtained will help conservation managers detect changes early and take timely measures.
