(Photo: Turtles spend most of their lives at sea)
Turtles tripping over one another. This is how the turtle team on Cousin Island Special Reserve described the emergence of 5 turtles on Saturday, all trying to nest on just 20 metres of beach at the same time.
Amidst the hustle and bustle of data collection, they made a startling discovery – one of the Hawksbill turtles was first tagged on the nature reserve in 1992! Another was an untagged newbie.
As female Hawksbills (Eretmochelys imbricata) reach maturity between 20 and 30 years, this meant the tagged turtle was more than 50 years old!
“We had two generations of females coming up at once, and if life were a Disney fairy tale, they would be mother and daughter!” says Christ Tagg, the conservation manager who coordinates monitoring.
Studying sea turtle populations presents a unique challenge as they spend most of their lives at sea. Scientists rely heavily on long-term monitoring of female turtles at their nesting beaches. Cousin has one of the longest monitoring programs for this species in the world, which started in 1972.
To identify female turtles returning to Cousin Island, titanium tags are applied to their flippers.
Titanium tags are applied to flippers to identify returning females
Turtles face numerous threats, including habitat destruction, climate change, and poaching. Long-term studies allow scientists to track changes, identify threats, and implement conservation strategies.
The thrilling discovery highlights the importance of protecting nesting beaches to ensure Hawksbill turtle survival.
“When Cousin Island was purchased in 1968 to save the Seychelles Warblers, it was discovered that the island was a vital nesting site for Hawksbill turtles. Soon after, a monitoring program was implemented, making it one of the longest in the world. The number of nesting Hawksbills has increased dramatically since then, as shown in a paper we published in 2010. The turtle population increased eight-fold since the early 1970s, directly attributed to the ongoing turtle conservation program on Cousin,” says Dr Nirmal Shah, the Chief Executive of Nature Seychelles, the NGO that manages the island.
Every nesting season, Hawksbill turtles make extraordinary journeys to their natal beaches to lay eggs. This homing instinct shows that they maintain a strong connection with their nesting grounds.
Cousin, at 29 ha, is one of the smaller islands in the granitic Seychelles. It is, however, the most critical nesting ground in the Western Indian Ocean region,” says Shah. “We have consistently seen many turtles returning to this site. Over the years, tag returns have also shown inter-island nesting on Cousin and other Seychelles islands. It’s a simple conservation message, nesting sites and turtles must be protected.”
Despite the heavy turtle traffic and turtles’ skittish nature on land, none of them gave up even when disturbed by the others. All of them laid eggs.
A Seychelles Fody picked mosquitoes off the laying turtle
“The first-timer’s inexperience was evident during the nesting process. Over an hour passed before passing eggs finally started. She strained for so long that we noticed small amounts of blood in her cloacal mucus. This could be a sign of infection or disease. However, it is more likely to be tears from contractions or the cloacae stretching for the first time. Either way, she soldiered on to lay. She had some company throughout,” says an excited Chris, who also observed the bizarre moment a Seychelles Fody picked mosquitoes off the laying turtle. “She was bouncing around the turtle snatching mosquitos out of the air and plucking them off her skin. She even took one off the eyelid!”