Leatherback sea turtle

The leatherback is a very big sea turtle.

It does not have a hard shell. Instead, it has thick and oily skin. This skin feels like leather.

The turtle has seven ridges on its back. These ridges look like strings on a musical instrument.

It uses large flippers to swim. These flippers help it move through the water. It can dive very deep into the ocean.

This turtle lives in many parts of the world. It is a very special animal.

The leatherback sea turtle is the largest living turtle.

It is also a very heavy reptile. Most turtles have a hard shell. The leatherback is different. It has thick, oily skin. This skin covers small bone parts. We call these parts osteoderms. This makes the shell feel like leather.

Seven ridges run down the turtle's back. These look like strings on a lute. A lute is a musical instrument. The leatherback has a teardrop shape. This helps it move fast through the water. It has very large front flippers. These flippers help it swim in the open ocean.

These turtles dive very deep. They can go down 1,200 meters. To stay warm in cold water, they move a lot. Constant swimming makes heat in their muscles. They also have fat to keep warmth in. The leatherback has no teeth. Instead, it has sharp spines in its throat. These spines help it swallow jellyfish.

The leatherback sea turtle is a truly amazing creature. It is the largest living turtle in our world today. It is also the heaviest reptile that is not a crocodile.

These turtles are special because they do not have a hard, bony shell. Instead, they have a flexible carapace covered in oily flesh and leather-like skin. This skin covers tiny bone pieces called osteoderms. These osteoderms are joined by zig-zag shapes called sutures. This design helps the shell stay strong but also stay flexible. This flexibility is very important for the turtle. It allows the shell to expand when the turtle takes in air. It also lets the shell contract when the turtle dives deep into the ocean.

Watching a leatherback move through the water is like watching a swimmer. They have a teardrop-shaped body that is very hydrodynamic. This shape helps them glide easily through the sea. They use two large front flippers to power themselves forward. These flippers are the largest in proportion to the body of any living sea turtle. They do not have any claws on their flippers.

Instead of teeth, they have a different way to eat. They have points on their upper lip to catch food. Inside their throat, they have backwards spines. These spines help them swallow jellyfish and stop the prey from escaping. This is a very clever way to eat in the deep ocean.

People have been studying these turtles for a long time. A man named Domenico Agostino Vandelli first named the species in 1761. He named it after an animal found at Ostia. Later, a French scientist named Henri Blainville created the name Dermochelys. In 1843, Leopold Fitzinger put them into their own family called Dermochelyidae. These turtles have a very old history. Their relatives have lived on Earth since the Cretaceous period. This was over 110 million years ago. They are related to other sea turtles, but they split into their own group about 49 to 70 million years ago.

Leatherbacks are famous for being able to live in many places. They have a global range that reaches from Alaska to New Zealand. They can even swim near the Arctic Circle. They live in all tropical and subtropical oceans.

Some adults can grow very large. They can reach a long length and weigh a lot. The largest specimen ever found was at Sandspit in Pakistan. In the Atlantic, many turtles visit Gabon in Africa. Nearly 30,000 turtles visit Mayumba National Park each year. However, the number of nesting females is going down. In 1980, there were about 115,000 females nesting every year. Now, there are only about 26,000 to 43,000.

These turtles are also champions of the deep sea. They are some of the deepest-diving animals in the ocean. They can dive down to 1,200 meters.

To stay warm in cold water, they use a special trick. They do not rest very much. They might only rest for 0.1% of the day. All that constant swimming creates heat in their muscles. They also have a thick layer of fat to keep the warmth in. This helps them keep a warm body even in freezing water. They are also very fast. One record says they can move at 35 km/h in the water. This makes them the fastest reptiles in the sea.

The leatherback sea turtle, known scientifically as Dermochelys coriacea, is a remarkable marine reptile. It is the largest living turtle species on Earth. It also holds the title of the heaviest non-crocodilian reptile.

Unlike most other turtles, it does not have a hard, bony shell. Instead, it possesses a flexible carapace covered in oily flesh and leather-like skin. This unique structure gives the turtle its common name. This species is the only living member of the genus Dermochelys and the family Dermochelyidae. Because of its unique anatomy, it is easily distinguished from all other modern sea turtles.

The leatherback's shell is a masterpiece of biological engineering. It lacks the hard scutes found on other turtles. Instead, the skin contains embedded, tiny bone pieces called osteoderms. These osteoderms are made of hydroxyapatite and collagen tissue. They have jagged edges often called teeth. These pieces are connected by a configuration of interpenetrating extremities known as sutures. These sutures create flexible joints in a zig-zag pattern. This design allows the carapace to move both in and out of plane. This flexibility is vital for survival. It allows the carapace to expand when the turtle breathes in air. It also allows the shell to contract when the turtle dives deep into the ocean.

This structure helps the turtle withstand the high hydrostatic pressure of deep dives.

Physiologically, the leatherback is built for life in the open ocean. It has a highly hydrodynamic, teardrop-shaped body. This shape reduces drag as it moves through the water. The turtle uses two large front flippers for propulsion. These flippers are the largest in proportion to body size among all living sea turtles. They lack claws and are adapted for efficient swimming. To eat, the leatherback does not use teeth. Instead, it has points on the edges of its upper lip. It also has backwards-pointing spines inside its esophagus. These spines help the turtle swallow prey and prevent it from escaping.

Leatherbacks are also unique among reptiles for their ability to manage body temperature. They can maintain high body temperatures even in cold water. This is achieved through several specialized features. They have an extensive covering of brown adipose tissue, which is a type of fat. They also use countercurrent heat exchangers. These are systems in the flippers and around the trachea that help retain warmth. While some thought they had a high resting metabolism, recent studies suggest a different method. Leatherbacks maintain heat through a very high activity rate. They may spend as little as 0.1% of their day resting. This constant swimming creates heat within their muscles.

The history of the leatherback is well-documented by scientists. Domenico Agostino Vandelli first named the species in 1761. He originally called it Testudo coriacea. In 1816, the French zoologist Henri Blainville created the genus name Dermochelys. Later, Leopold Fitzinger established the family Dermochelyidae in 1843. Evolutionarily, leatherbacks are very ancient. Their relatives have existed since the Cretaceous period, over 110 million years ago. The leatherback family split from other sea turtle families approximately 49 to 70 million years ago.

These turtles have a massive global distribution. They are found in all tropical and subtropical oceans. Their range even extends into the Arctic Circle and as far north as Norway and Alaska. They can be found as far south as New Zealand and South Africa.

Some adults grow to incredible sizes. A verified specimen found in Pakistan measured a large curved carapace length. In the Atlantic, the Mayumba National Park in Gabon is a major site. Nearly 30,000 turtles visit these beaches every year. However, the species faces significant challenges. Global nesting populations are declining. In 1980, an estimated 115,000 females nested annually. Recent estimates show only 26,000 to 43,000 females nest each year.

Leatherbacks are true champions of the deep sea. They are among the deepest-diving marine animals in the world. They have been recorded diving to depths of 1,200 meters.

Most of their dives last between 3 and 8 minutes. However, they can occasionally perform much longer dives of 30 to 70 minutes. They are also incredibly fast swimmers. One record from the Guinness Book of World Records listed their speed at 35 km/h. This makes them the fastest-moving reptiles in the ocean. Their ability to dive deep and swim fast allows them to follow their prey, such as jellyfish, across vast distances.