Wednesday, 30 May 2018

The green turtle on Denis island

The Green Turtle is part of an order of reptiles that have been on this Earth for 220 million years. They survived the extinction that wiped out the dinosaurs, several ice ages and now as a result of direct and indirect human action they could disappear! The green turtle (Chelonia mydas) for years was hunted as a source of meat. This, coupled with the pollution of the world’s oceans has led to drastic declines in numbers of turtles. An estimated 170,000-180,000 green turtles remain. This may seem a large figure however compared to seven billion humans, some perspective can be seen! Worldwide awareness is now the highest it has ever been and efforts are being made at small and international levels to conserve the turtle species.

The Seychelles is perhaps the best example in the Indian Ocean of turtle conservation. Several NGOs and experienced researchers are working with the government and local community to bring about change to save these ancient species. As a result of the continued efforts happening and strict anti-poaching laws in the Seychelles, the turtles that return each year are afforded protection and it is hoped this will lead to population increase. 
Photo: Green turtle track (CTagg) 

Here on Denis Island, the green turtle nesting season has begun. Emergences at night have been seen over the last few weeks with 10 emergences recorded on the 21st of May this year!  An emergence is when the female returns to the beach she most likely hatched from decades before to lay her own eggs. This is the only time a healthy turtle will ever return to land. The green turtles emerge under the cover of darkness usual at high tide and drag themselves up the beach to lay anywhere between 75-200 eggs before returning back to the ocean.

Denis Island is not just used as a nesting site for this endangered species, but the waters around the island are a crucial foraging ground for immature turtles. The seagrass meadows are perfect for the young turtles offering both food for their development and safety for the large predators found in deeper water. In return the turtle grazing opens up the meadows allowing for a richer invertebrate and fish community, making them a crucial component of the ecosystem! Turtles on Denis can be frequently seen from the shore coming up for air and swimming in the shallows grazing on the seagrass. 
Photo: Immature green turtle swimming a few metres from shore (CTagg)
Adult turtles on very rare occasions can be seen mating in the sea. On the morning of the 21st of May, Conservation Officer Chris Tagg observed a mating event in the shallows at the south end of Bois Blanc. The mating couple were a few meters from the shore with at least another five males in the vicinity vying for an opportunity to mate with her as well should the mating male be displaced. To ensure he does not slide off or get washed away from the female, the male turtle will secure himself with his front flippers.  The next day, Conservation Officer Juan Michel spotted them again still in the process of mating!

Photo set: Top Male mounting female during breeding attempt with a second male bottom circling nearby (CTagg)

Events such as mating and high levels of emergence are signs for optimism in these times when conservation is fighting to change people’s perspectives on wildlife and the natural world in general and open their eyes to the impacts we are having on the Earth.

It is hoped that each island here in the Seychelles will have some form of protection or a dedicated team to monitor the turtles. Protecting one island on a chain is good but having some form of protection across multiple is excellent! If you would like to help in any way to the conservation efforts on Denis Island, report turtle sightings to the conservation team.

No comments:

Post a Comment