How Many Leatherback Turtles Are Left In The World?

How Many Leatherback Turtles Are Left In The World?

 

Leatherback turtles

Leatherback turtles are a species of turtle characterized by their lack of a bony shell and their distinct large size.

Leatherback turtles are in fact so large that they are listed as the fourth heaviest reptile behind three species of crocodile. They have been known to weigh up to 900 kg and grow up to 1.6 metres.

The turtle’s name emanates from the leathery texture of its carapace which is in other species a hard, bony shell.

Leatherback turtles’ conservation status is classified as “Vulnerable.” Their bodies have perhaps what is described as the most hydrodynamic body shape that resembles a large teardrop.

Their anatomy closely resembles other species of turtles in that they have flattened forelimbs that are specially adapted for swimming in open ocean waters.

The front flippers are distinctly larger with claws being absent on both front and back flippers.

Leatherback turtles are also listed among the deepest diving marine-dwelling animals known to man.

It is worth mentioning that leatherback turtles’ diet mainly consists of jellyfish and other soft-bodied marine animals. Find more on what leatherback turtles eat here.

So how many leatherback turtles are left in the world and what are the threats to leatherback turtles? Let’s discuss these among other concerns related to this species of giant turtle below.

 

How Many Leatherback Turtles Are Left In The World?

 

Populations of leatherback turtles are distributed between four distinct zones. These are;

  • Pacific Ocean
  • Indian Ocean
  • Atlantic Ocean
  • South China Sea

 

The Pacific Ocean Leatherback Turtle Population

Leatherback turtle Pacific populations are spread in the region between Indonesia, Papua New Guinea, parts of the Northern Hemisphere which include North America.

Other areas where leatherback turtles nest are the West coast of the South American continent, and parts of the southern hemisphere.

Australian leatherback turtles nest along the Queensland coast from Bundaberg to the tip of Arnhem land. These rookeries have always been small and have dwindled in numbers recently all along the QLD coast in Australia.

Experts estimate around two thousand three hundred adult females in the Pacific region.

How Many Leatherback Turtles Are Left In The World?

The Indian Ocean Leatherback Turtle Population

While little research has been conducted on leatherback turtles dwelling in the Indian Ocean, marine life conservationists assert that the Indian Ocean population is genetically distinct from the rest of the species.

 

The Atlantic Ocean Leatherback Turtle Population

It is estimated that leatherback turtle numbers are higher in the Atlantic region thanks to an abundance of jellyfish; their primary prey.

Their range covers the region off the Canadian coast, to Costa Rica and the biggest leatherback nesting site in Gabon.

The latter plays host to over 30,000 leatherback turtles each year between the months of October and April.

 

The South China Sea Leatherback Turtle Population

Other suspected leatherback turtle nesting sites are located within the South China Sea region mainly Malaysia.

The region was once considered to be the world’s biggest nesting site, but consumption of turtle eggs has led to their steady decline.

 

Threats To Leatherback Turtle Populations

Leatherback turtles similar to other species of turtle are at their most vulnerable after hatching.

In their early life stages, leatherback turtles are vulnerable to predation by shorebirds, crabs and small mammals.

Hatchlings that manage to reach the water face the threat of predation by fish and other predatory marine life.

Adult leatherback turtles have only the threat of being eaten by large sharks. Mainly the tiger shark.

The reason for this is that their flesh has too much fat and oil making it unpalatable.

Human Threats 

The biggest threats to leatherback turtles are however related to human activities.

Pollution, accidental catches, and entanglement in fishing nets are the most deadly threats to leatherback turtles.

Ingestion of plastic bags has also been known to be fatal as it causes intestinal blockage and malabsorption.

The loss of breeding rookeries from developments and erosion of beaches from developments in the area which affect the tides.

 

How We Can Reduce The Decline Of Leatherback Turtle Numbers

Humans are the number one cause for the decline of how many leatherback turtles are left in the world. It is up to everybody to stop polluting the land and waterways. It is very easy for plastics on land to end up in the oceans of the world.

How Many Leatherback Turtles Are Left In The World?The protection of rookeries will assist in the leatherback turtle numbers to start rising. This includes the human consumption of eggs.

 

It is our responsibility to reverse the effects we have caused and to protect this magical species of turtle.

 

What Do Leatherback Turtles Eat?

What Do Leatherback Turtles Eat?

What Do Leatherback Turtles Eat?

What Do Leatherback Turtles Eat?

What begs the question however, is just how such a large animal survives on a jellyfish diet, which is essentially water, and a small amount of protein and fat.

The Leatherback has quite a long oesophagus leading from the mouth through to the back of the body, and then looping up again until it reaches the stomach.

Essentially, it acts as a storage unit, and as food is digested and released, more food enters the stomach; it’s like a never-ending procession of food through the body.

 

Leatherback Turtle Mouth

With large food requirements, these turtles are always on the search for food. The oesophagus is lined with papillae, sharp, keratinized prongs that allow this species to mainly eat jellyfish and other soft-bodied animals.

These prongs, made from cartilage, line the throat allowing the turtle to grip onto the jellyfish. Without these prongs, as the turtle expels excess water, the jellyfish would slip straight back out.

The papillae also help to protect from jellyfish stings while eating.

 

Swimming With The Leatherback Turtle

With what is likely to be one of the most terrifying mouths in nature, the Leatherback Turtle is unfortunately in decline across the world.

Once prevalent in oceans across the world (apart from the Arctic and Antarctic), many of these turtles fall victim to human activity as well as natural prey.

Often known as the Lute Turtle or Leathery Turtle, the Leatherback turtle is the largest of all living turtles and is only beaten by three crocodile species when comparing reptiles by weight.

Leatherback turtles are easily distinguished from other sea turtle species– the carapace is covered by skin and oily flesh rather than a bony like substance and ridges along the carapace.

 

Leatherback turtles to dive to depths of over 1,200 metres, staying down for up to 85 minutes. Leatherback turtles are the deepest diving reptiles. 

What Do Leatherback Turtles Eat?

Leatherback Turtle Size

Starting out between 15 – 30gms and at just 5 – 7 centimetres long on average at birth, Leatherback turtles end up being the largest sea turtle species across the world.

Fully grown, they can reach lengths of two metres and can weigh up to 900kg. In comparison, the smallest sea turtle is the Olive Ridley or Pacific Ridley which only reaches one metre in length and averages out at 45kg in weight once fully grown.

 

Where Do Leatherback Turtles Travel?

Leatherback turtles can be found in almost all oceans in the world and while they feed in temperate waters, their breeding is done in tropical areas.

They are oceanic and it is rare to find one close to shore, particularly here in Australia, unless they are one of the few laying eggs in the Great Barrier Reef region.

It is thought that Leatherback turtles take one of the longest migration routes between breeding areas and feeding areas, with an average of 6,000km each way – that’s just under a return trip between Brisbane and Perth.

Despite feeding in temperate regions and breeding in tropical regions, they have been found in waters with temperatures as low as 4 degrees Celsius (approx. 40 degrees Fahrenheit) and are the only reptile known to remain active at these low water temperatures.

 

Life As A Leatherback Turtle

There are four main subpopulations of the Leatherback turtle found across the world – the Atlantic subpopulation, the Pacific subpopulation, the South China Sea subpopulation and the Indian Ocean subpopulation.

Atlantic Leatherback turtes are found in waters from the North Sea to the Cape of Good Hope, feeding in areas near Quebec and Newfoundland, and nesting in the regions of Trinidad and Tobago, Gabon and Antigua.

The coastline of the Mayumba National Park is home to one of the largest nesting populations with almost 30,000 turtles visiting every year. Small nesting areas are alsoo located on the east coast of Florida, and in Costa Rica.

Pacific Leatherback turtles have two distinct populations, the first nesting on beaches around Indonesia and the Solomon Islands, and feeding in regions such as California, Oregon and Washington to feed. The other finds food in the regions around South America and nest in Mexico, El Salvador and Nicaragua.

Unfortunately, the Leatherback turtles in the South China Sea region, namely Malaysia, have all but disappeared. In years past there could be up to 10,000 nests in Terengganu.

However egg consumption by humans have added to the decline. So far, conservation efforts have failed.

The last sub-population is those living in the Indian Ocean. There is little known about the turtles living in this region, however it is thought that nesting areas are around Sri Lanka and the Nicobar Islands.

 

What Do Leatherback Turtles Eat?

Threats To Leatherback Turtles

It is estimated that only one in a thousand hatchlings survive to adulthood and like many other creatures, one of the largest threats to the Leatherback turtle is human activity, and this happens from birth through to old age.

In some areas of the world, turtle eggs are taken from nests to be used as food or aphrodisiacs. They also fall victim to fishing nets and lines, boats and plastic, which is often mistaken for jellyfish.

Some Leatherback turtles have been found with almost 5kgs of plastic in their stomachs.

Other predators strike while the iron is hot so to speak, and many hatchlings don’t make it to the water.

Fish, dogs, seabirds, crabs, saltwater crocodiles, lizards, dingos and foxes all prey on eggs and hatchlings, while for adult turtles, the main predators are sharks, killer whales and crocodiles.

According to the World Wildlife Fund, the Pacific population of Leatherbacks have declined the most over the last 20 years, with as few as 2,300 adult females thought to remain in the wild; this means the Pacific Leatherback turtle is the more endangered marine turtle population.

It is also thought that the Atlantic population, while currently more stable, will start to decline as fishing increases.

You can find out more about how many leatherback turtles are left in the world here.

 

Where Can You See Leatherback Turtles

You’ll find Leatherback turtles in coastal countries across the world. Found in all tropical and subtropical oceans, at times they also extend into the Arctic Circle.

From Alaska and Norway through to the southern tip of New Zealand, you may be lucky enough to spot a Leatherback turtle.

There are turtle rookeries along both the Queensland coastline where you may get the rare opportunity to see Leatherback turtles lay eggs and hatch.

They have been known to occasionally feed and nest within the Great Barrier Reef Marine Park, and have sporadic nesting points throughout Queensland.

With the Leatherback turtle in decline across the world, developing safe rookeries is essential as is ensuring that items such as plastics are kept out of the water.

While natural predators will always be around, there are plenty of steps we can take to ensure the future of these turtles.