TURTLES
Sea turtles are graceful, ancient and endangered. There are seven species of sea turtles, with four of them commonly found in South African waters - green turtles, loggerheads, leatherbacks (the biggest of the turtles) and critically endangered hawksbills. As reptiles, turtles were around before dinosaurs. Depending on which journal you read, they have existed for between 230 million to 260 million years and have survived at least two mass extinction events.
Modern sea turtles all arose from a common ancestor about 110 million years ago. In addition to the four named above, there's also the flatback, the critically endangered Kemp's ridley (the smallest of the turtles) and the olive ridley. In South Africa it's the loggerheads and leatherbacks that nest on beaches in northern KwaZulu-Natal over the height of summer, with their eggs taking about two months to hatch and the babies heading out toward the warm Agulhas current.
But there are predators waiting for them as they make their way to the shore and increased construction has also meant that some hatchlings will follow the artificial lights and not make it to the sea. There are also nesting beaches that aren't access controlled and people drive on them, sometimes crushing turtle eggs buried beneath the sand. If the hatchlings make it into the ocean there are also predators waiting for them there as well as ever increasing amounts of plastic. In the wild, only one or two out of every 1,000 turtle hatchlings survive to adulthood and those odds are worsening because of increased pollution, climate change, and other hazards caused by human activity.
But it's not all bad news. There are turtle conservation centres all round the world helping to rescue and rehabilitate stranded turtles and there is also much more research going into what's called the "lost years." It's not yet fully understood where small turtles go and what they do in the years before they're adults and spend more time on nearshore reefs. If that were better understood, it's possible that certain routes or areas could be better protected. One difficult thing with turtles, though, is how highly migratory they are and how far they can swim. They can literally cross vast oceans, potentially countless times in their lives.
Modern sea turtles all arose from a common ancestor about 110 million years ago. In addition to the four named above, there's also the flatback, the critically endangered Kemp's ridley (the smallest of the turtles) and the olive ridley. In South Africa it's the loggerheads and leatherbacks that nest on beaches in northern KwaZulu-Natal over the height of summer, with their eggs taking about two months to hatch and the babies heading out toward the warm Agulhas current.
But there are predators waiting for them as they make their way to the shore and increased construction has also meant that some hatchlings will follow the artificial lights and not make it to the sea. There are also nesting beaches that aren't access controlled and people drive on them, sometimes crushing turtle eggs buried beneath the sand. If the hatchlings make it into the ocean there are also predators waiting for them there as well as ever increasing amounts of plastic. In the wild, only one or two out of every 1,000 turtle hatchlings survive to adulthood and those odds are worsening because of increased pollution, climate change, and other hazards caused by human activity.
But it's not all bad news. There are turtle conservation centres all round the world helping to rescue and rehabilitate stranded turtles and there is also much more research going into what's called the "lost years." It's not yet fully understood where small turtles go and what they do in the years before they're adults and spend more time on nearshore reefs. If that were better understood, it's possible that certain routes or areas could be better protected. One difficult thing with turtles, though, is how highly migratory they are and how far they can swim. They can literally cross vast oceans, potentially countless times in their lives.
Bheni, the green turtle's route over 288 days after being released by the Two Oceans Aquarium Foundation's Turtle Conservation Centre
One amazing thing about turtles is that the females, when they're mature adults, which can take decades, will mate with a number of males and store the sperm for up to a few years before climbing onto a beach in the region where they hatched and over a period of weeks laying a number of clutches of eggs with different genetics due to the different males that were involved in the process.
Another amazing thing is that the temperature of the sand that the eggs are in determines the sex of the hatchlings. The warmer the sand, the more likely the hatchlings will be female. This is, of course, problematic in an age of global warming because too few male turtles are emerging from the nests. Interestingly though, sea turtles of one species will sometimes mate with sea turtles of another species, creating hybrid turtles, which can be fertile and healthy. Six hybrid combinations have so far been found between five species; olive ridleys, Kemp's ridleys, loggerheads, hawksbills and green turtles (Brito et al., 2020).
In Africa, the Cape Town-based Two Oceans Aquarium Foundation's Turtle Conservation Centre is the biggest of its kind on the continent. Sea turtles, except for nesting females, never come up onto beaches in South Africa unless they are in distress. Many of those that are stranded and found are taken to the centre in Cape Town where they receive the highest levels of medical care, including CT scans and physiotherapy where needed, and specialised nutrition. The centre has successfully rehabilitated and released hundreds of turtles (mostly loggereads, but also green turtles and hawksbills) back into the ocean.
If you find a stranded sea turtle, please follow the procedure set out in the pictures below. Most importantly, don't put the turtles back in the water. Other ways to help include "adopting a turtle," becoming a member of the Turtle Rescue Network if you live along or near South Africa's Eastern Cape or Western Cape coastlines, donating to the Turtle Conservation Centre, stop using single-use plastics, cleaning up beaches and rivers and joining the turtle community.
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“I learn as much from a turtle as from a religious text.” The 14th Dalai Lama