A sea turtle’s struggle for survival starts from the moment it emerges from its shell.
Having spent a gestation period of six to seven weeks under the cover of half a metre of sand, the hatchling, measuring a mere 5cm in length, must crawl out from under its heavy protective shelter and all the way down the beach to the sea, propelled by tiny flippers that could appear poorly adapted for the job.
On this already arduous journey, it must also evade – if it can – the predatory attention of crabs, seabirds, and even rats, feral dogs or foxes. Meanwhile, artificial light can disorient the hatchlings, as they use moonlight to navigate towards the sea, and reduce their chances of survival.
Assuming it survives these initial hazards, more dangers await once the hatchling enters the apparent safety of the ocean. Sharks, other fish, and octopuses will all welcome the chance to snap up a turtle snack should it come their way.
The odds are certainly stacked against these marine reptiles. In fact, there’s a popular notion that only one in 1,000 hatchlings make it to adulthood to breed. But the truth is, there is much we don’t know about sea turtles, including their survival rate, because, apart from when the females come ashore to lay their eggs, they spend their entire lives at sea.
We do know that their numbers have been dropping all over the world, though.
There are seven species of sea turtles in the world: loggerhead, leatherback, olive ridley, green, Kemp’s ridley, hawksbill, and flatback. Of these, the first three are classed as vulnerable by the world’s wildlife conservation body, the International Union for Conservation of Nature (IUCN); greens are endangered, Kemp’s ridley and hawksbill are critically endangered, and there isn’t enough data to assess the status of flatbacks.
Ras Baridi, an area just north of the city of Yanbu on the west coast of Saudi Arabia, is unusual according to Dr Hector Barrios-Garrido. The sea turtle specialist is part of a team of scientists from the Beacon Development Company (BDC), a wholly-owned subsidiary of the King Abdullah University of Science and Technology (KAUST) that’s heavily involved in the conservation efforts.
Extensive research conducted by KAUST’s Professor Carlos M. Duarte, one of the world’s leading authorities on marine science, has shown that this stretch of coastline is the most important turtle nesting site – or rookery – in the whole of the Red Sea. In some years, 360 green turtles, plus a handful of hawksbills, come ashore to lay their eggs on Ras Baridi’s sandy beach. Only Zabargad Island, on the other side of the Red Sea, off the coast of Egypt, has comparable numbers.
There’s also the fact that Ras Baridi is on the mainland – if you look around the world, the majority of sea turtle nesting sites are found on islands. One reason might be the abundance of seagrass in the area. Professor Duarte’s research suggests that Ras Biridi has the largest seagrass meadow in the Red Sea, perfect for breeding sea turtles that need a stable food source while laying their eggs.
To protect this special area and help reverse the odds in the turtle’s favour, the Ba’a Foundation – a Saudi Arabian non-profit organisation that focuses on preserving endangered species and natural habitats, as well as the country’s cultural and historical sites – has created the Ras Baridi Marine Turtle Conservation Initiative using KAUST’s research, and tasked the BDC with its implementation.
The central aim is to increase the number of hatchlings that emerge from their nests and successfully make that journey down to the sea. It’s seen as one of the key actions that will help to grow the sea turtle population, echoing their own strategy for survival, derived from evolution.
All sea turtles take decades to reach maturity – hawksbills, for example, are not ready to breed until they are between 20 and 40 years of age. But once they are ready to breed, it becomes a numbers game.
Female sea turtles breed on average every three years and as they get older, this frequency improves to every other year. During each reproductive year, they can nest up to five times, with a single female laying up to 100 eggs in each nest. The goal is to produce huge numbers of offspring in the expectation that at least some – despite the heavy death toll when they are very young – will live long enough to produce the next generation.
And until the past century or so, nature’s strategy has worked extremely well. This group of reptiles are some of planet Earth’s ultimate survivors, having been around more or less in the same form they now take for at least 180 million years.
A researcher with a nesting turtle
As Dr Barrios-Garrido puts it: “They survived the dinosaurs’ time, and now they are endangered. Are we humans worse than a meteorite?”
The immediate threats are obvious. All over the world, turtles have been exploited for their eggs, oil content, meat and intricate shells. They are also accidentally caught and drowned in commercial fishing nets, while chemical pollution and ingestion of plastic (plastic bags resemble jellyfish, one of their favourite foods) are becoming increasingly problematic. Loss of nesting beaches to developments, especially in tourist hotspots, is another massive issue. And of course, the aforementioned light pollution that’s endangering the species as soon as they hatch.
In the longer term, scientists are also concerned about what impact rising temperatures and sea levels could have. Temperature determines the sex ratio of a turtle clutch – the warmer it is, the more females there are – so global warming could lead to a gender imbalance unless the turtles migrate to a different latitude.
Rising sea levels, meanwhile, can result in lost nesting habitats and more nests failing if they are flooded by seawater before the eggs hatch. This has already led to large nesting failures in Ras Baridi over the past two years, according to Professor Duarte.
Sea turtles habitually return to their feeding and nesting grounds
