An Underwater Legend on the Verge of a Hasty Extinction

The mighty Leatherback turtle, who had swum the oceans when dinosaurs roamed the earth more than a hundred million years ago, is now facing extinction.

During our late-night authorised rides along the iSimangaliso beach to find the turtles, the local conservationist Peter Jacobs educates me on these fantastic sea creatures.

Leatherbacks are the world’s biggest turtles. They can weigh up to a massive 1000kg and reach up to 3m in length. Their body is dark, mottled blue-grey colour and the forelimbs are colossal. Leatherback turtle’s shell is delicate with a leathery texture, quite soft and flexible. Under their soft shell, they have a thick layer of insulating fat that keep their body warm in the coldest waters.

Leatherback turtle can hold their breath for up to 90 min. Their soft shell allows them to dive down cold temperatures of over 2,000 meter deep, their soft shell enables the body to compress and expand depending on the water depths.

These reptilian giants feed mostly on jellyfish and sea squirts, and need to eat up to two-thirds of their body weigh every day. Leatherback  turtle don’t have teeth , instead they have a oesophagus filled with hundreds of sharp pointy, backwards-facing spines called papillae, that goes down its oesophagus and to its gut.

Their powerful papillae help them to eat large number of the slippery jellies and stop the jellyfish from escaping out of their mouth.

Leatherback turtles reach maturity after 15-18 years. After mating at sea, mature females will return to their natal beaches for nesting,  while adult males live entirely at sea. A female Leatherback can store viable sperm from different males for up to 4 years.

Their life cycle begins with a female turtle laying eggs on the nesting beach. Commonly at night, the ritual consist of excavating a hole in the sand, laying around 100-120 eggs per nest, covering the nest with sand and returning to the sea.  Females stay close to shore for 3-4 months and come to the beach at 10-day intervals to lay eggs.

Adult females leave to the open sea to hunt for food and remain in the ocean for a ‘remigration interval’ of 2-5 years until they return to nest once again.

Excellent fast swimmers, Leatherback turtles, have the widest distribution of all sea turtles. They can be found in our Indian Ocean and as far as in the north as the USA, Alaska and New Zealand.

It’s only recently that scientists finally understood the soft ‘pink spot’ [pineal] in the Leatherback turtle’s head.

It’s a passage, a window for light to reach a part of their brain that acts as a biological clock. This “skylight”, allows the turtles to sense and time solar radiation that leads to changing seasons, and therefore turtles can tell when it’s time to migrate to warmer waters. Leatherbacks travel an average of 3,700 miles each way between breeding and feeding areas.

Studies suggest that Leatherback Turtles and other sea turtles use ‘magneto-reception, detecting the earth’s magnetic fields, to navigate- a built-in GPS.

South African waters also home four other sea turtles species, the Green Turtle, the Hawksbill, the elusive Olive Ridley and the endangered Loggerhead. Both local Leatherback turtle and the Loggerhead turtle will return to iSimangaliso to lay their eggs on the beaches where they were born.

Like as with crocodiles and other reptiles, the temperature of the eggs dictates the sex of hatchlings; temperatures below 25 degrees celsius produces males, while 28 degrees celsius or higher results in females. Due to global warming, the male numbers have drastically decreased, and females are most at risk when they come ashore for nesting. Habitat loss, poaching, accidental capture [bycatch], and pollution add to all the major threats to their survival.

Since 2014, Peter Jacobs and his partner Themba Ndlovu, have been operating the Ufudu Turtle Tours from Sodwana Bay, located on the Kwa-Zulu Natal coast of South Africa between St. Lucia and Lake Sibhaya.

‘Apart from being registered concessionaires with the iSimangaliso Wetland Park Authority, we are also the only operator permitted to conduct turtle tours in the area’, says Peter.’ Our aim is to make the tourist and the general public aware of the plight of our endangered turtles and their struggle for survival. We also strive to give the tourist a “once in a lifetime experience”, while focusing on the importance of the preservation and conservation of our wildlife and the environment.’

Ufudu Turtle Tours operates within a world heritage site, and they are governed by the iSimangaliso Wetland Park Authority, with specific guidelines to preserve and conserve the environment while promoting tourism in the area.

The tours season runs from November to May every year, and they offer beach drives around the low tide times and only in the evenings or late at night when the turtles emerge from the ocean to nest. The nesting season is usually from November to the end of February, and the hatching season from the middle of January to the end of April each year. All nests are GPS marked to increase sightings of the hatchlings as they make their way back to the ocean.

iSimangaliso beaches are home to the endangered Leatherback and Loggerhead turtles, who return year after year to lay their eggs on these beaches.

Restrictions on pedestrian and off-road vehicle activity to protect seasonal beach-nesting species should be something everyone could accept and support; unfortunately, this isn’t the case.

There are still many beaches in South Africa that allow motor vehicles into the beaches where endangered species such as the Leatherback and Loggerhead turtles come to nest every year along our Indian Ocean beaches.

It’s estimated that only about one in two and a half thousand Leatherback turtle hatchlings survive to adulthood. Tire ruts left by vehicles add to the survival challenges the already vulnerable hatchlings face. If they don’t make it to the ocean fast,  crabs and other predators will catch and kill the hatchings. Eggs are often taken from the nest by poachers to be used for ‘muti’ or traditional medicine practice, and the hatchlings are use as fishing bait.

Every year hundreds of thousands of sea turtles fall victim to fishery ‘bycatch’ or accidentally get entangled in abandoned fishing nets. Trapped in the mass fishing nets, the turtles are dragged through the water with no access to the surface to breathe, causing them to drown. Others die from ingesting plastic debris that looks like jellyfish when floating on the ocean.

The last three stages towards animal extinction are: critical endangered, extinct in the wild, and extinct. Leatherback sea turtles are just one stage away from extinction. They are adapted to live in the open sea without boundaries, and it’s very difficult to keep them in captivity; not only they required a steady diet of jellyfish, but they also aren’t able to swim in a reverse direction and constantly swim into the walls of a holding tank.

Once upon a time, our oceans were the world’s largest wildlife reserves. Destruction of habitat and pollution are the biggest causes of all current extinctions. Our planet earth can’t operate without healthy ocean, and we humans rely entirely on this finely tuned life-support machine. As species disappear, their extinctions will directly affect our health and our chances for survival as a species.

‘Humans, we are the most intelligent species on earth, but we are also the most destructive ones’, says Peter.

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