Let’s know about leatherback turtles

The leatherback turtles are the largest living sea turtle. Its history dates back to the age of dinosaurs. It has a soft skin that allows it to dive deep. It faces threats such as illegal hunting and climate change and is listed as a “vulnerable” species. Its population is declining, and protecting its young is crucial to its survival.

In the vast ocean, there lives an ancient creature – the leatherback turtle. As the largest existing sea turtle species, they occupy a place in biodiversity with their unique morphology and habits. The history of leatherback turtles can be traced back to the dinosaur era, and their existence has witnessed the evolution of life on Earth.

Sea turtle

Leatherback turtles are a unique type of sea turtle. Instead of a hard shell, they have a soft and tough skin armor. This special skin structure allows leatherback turtles to dive freely in the deep sea, even to a depth of 1,200 meters.

Leatherback turtles are huge, with the largest individual recorded to be nearly 3 meters long and weighing more than one ton. They can live up to 50 years and travel tens of thousands of kilometers every year, making them long-distance migrants in the ocean.

The origins of the leatherback turtle can be traced back 260 million years to a small reptile in South Africa called Eunotasaurus africanus. Over time, these ancient reptiles evolved into modern turtles, including the leatherback turtle.

One of the leatherback’s ancestors, Odontochelys semitestacea, is the earliest know turtle to have a plastron. While another ancient turtle, Proganechelys, lived during the age of dinosaurs and had a hard shell and sharp bone spurs, and is a distant relative of the modern leatherback.

The leatherback turtle’s appearance is very different from other sea turtles. They have seven longitudinal ridges of bone on their backs, which replace the hard shell of other sea turtles, making their backs look like strips of leather sewn together. The leatherback turtle’s skin is medium blue-gray to black, with a pale pink belly. The forelimbs are long and powerful, while the hind limbs are shorter, and they have no claws on their flippers.

Solitary animals

Leatherbacks are solitary animals in behavior and rarely interact with others of their kind, except during the breeding season and when laying eggs. These Leatherbacks turtles are masters of deep sea diving, spending most of their time in the deep ocean, only coming ashore to lay eggs. Leatherbacks are not particularly aggressive, but if they feel threatened, they will bite with their sharp beaks, causing severe bruises and even broken bones.

Leatherbacks are found in tropical and temperate waters on both sides of the United States, including Hawaii, Puerto Rico, the Virgin Islands, Indonesia, and Africa. Their range extends from terrestrial breeding areas to deep ocean waters below 4,000 feet.

In terms of diet, leatherback turtles feed mainly on jellyfish and sea squirts and are know as gelatinous feeders. They have backward-facing spines in their mouths and throats, an adaptation that helps them hunt gelatinous prey. Leatherback turtles can consume almost their own body weight in jellyfish every day.

However, leatherbacks also face many threats. Adult leatherbacks have few natural predators due to their large size and ability to dive deep. But their eggs and hatchlings are often attack by raccoons, crabs, and birds. Unfortunately, leatherbacks also face many threats from humans, including illegal hunting, theft of their eggs, ingestion of human waste such as plastic bags, and entanglement in fishing nets.

IUCN

Climate change is also a factor in the decline of leatherback turtles. Which are sometimes hit by marine vehicles. As a result, the International Union for Conservation of Nature (IUCN) lists leatherback turtles as “vulnerable.” Despite ongoing conservation efforts and some positive results, leatherback turtles are still at risk of extinction in the coming decades if conditions do not improve.

In terms of reproduction and life cycle, scientists are unsure when leatherbacks reach sexual maturity, but it is generally believe to be between 9 and 20 years old. They are easiest to study on land, but once in the ocean, female leatherbacks only emerge from the water to lay eggs, while males never leave the water at all.

Leatherbacks do not lay eggs every year, which may be part of the reason for their decline. However, they do lay multiple clutches of eggs each breeding season. Every two to four years, a female leatherback will come ashore to lay eggs after mating and may lay eggs multiple times during the season.

Reproductive process

Female turtle will lay about 100 eggs in the sand, and repeat this process every eight to twelve days for a short period of time, for a total of four to seven clutches, or 400 to 700 eggs per season. After two months of incubation, the eggs will hatch into hatchlings.

Their journey from the nest to the ocean can be the most dangerous part of a leatherback’s life, as this is when they are most vulnerable to predators and poachers.

Leatherback turtle populations are declining. In particular, the Pacific Ocean is in decline and at risk of extinction, with fewer than 3,000 adult females believed to remain. In 1980, the world’s known adult female population was over 100,000.

At the last count, there were only about 25,000 to 35,000 adult females left. The spawning grounds in Malaysia have completely disappeared, which is a bad omen. Nesting grounds elsewhere have also declined severely, from thousands of nests per year to just a few.

The male population of leatherback turtles is unclear, but at least for the Pacific population, scientists worry that it will drop below 1,000 by 2030.

Because male leatherbacks do not leave the water during the breeding season like females, they are difficult to study, and population estimates are based on the fact that approximately 10% of the hatchlings are male and 90% are female. Therefore, the male adult population is estimate to be approximately 10% of the female population.

In 2020 and 2021, ecologists successfully released tens of thousands of hatchlings back into the sea and reduced poaching of eggs to just 1% of the total egg population.

Keeping the hatchlings safe is critical to ensuring the survival of the leatherback population, and if these numbers are sustain.