Leatherback Sea Turtle

A leatherback lays her nest at night. Hilary Frandsen photo.

A leatherback lays her nest at night. Hilary Frandsen photo.

Species name: Leatherback sea turtle

Nombre en Espanol: Tortuga Laud or Baula

Latin Name: Dermochelys coriacea

Family: Dermochelyidae

IUCN Endangered Status: Critically Endangered

 

 

 

 

 

Hilary Frandsen photo.

Hilary Frandsen photo.

Description

This species is a highly migratory, pelagic (deep water) species. It has a streamlined body and is capable of dives of up to an estimated 4,265 feet. Its high fat content provides insulation and gives it the ability to maintain deep body temperatures at a level above that of the surrounding cold water.

The leatherback can reach enormous proportions. It is the largest living turtle, ranging from 550 to 1,200 pounds (295 to 545 kilograms) and growing to lengths of 6 to 8 feet (1.8 to 2.4 meters). There are records of at least one specimen weighing 2,000 pounds (907 kilogram).

It is the only living species of family Dermochelyidae. "Derma" is Greek for skin or leather, and "khelus" is Greek, meaning tortoise.

Leatherbacks lack the typical bony shell covered with horn-like scutes. Instead, they have a cartilaginous shell with a matrix of hexagonal bones embedded in it. The leatherback is distinctly triangular in shape, having a prominent keel down the center of the upper shell (carapace), flanked by three more keels on each side — seven in all. The skin is black or dark brown, spotted with white. Hatchlings of this species have white coloration on the edges of their flippers.

Somewhat surprisingly, their diet is almost exclusively jellyfish. Many die each year when they become impacted from swallowing discarded plastic bags, mistaken for jellyfish.

 Size: The largest living turtle, can get up to 7 feet in length

Weight: can range from 550 to 1,200 pounds

Diet: eats primarily jellyfish

Lifespan in wild: estimated around 45 years

Habitat and Distribution

The leatherback's habitat is typically tropical or subtropical seas, but it has been found as far north as Nova Scotia. Major nesting beaches in the western hemisphere are on the Pacific Coast of Mexico at Barra de la Cruz, Chacahua, Oaxaca, Mexiquillo, Michoacan, and at Tierra Colorado, Guerrero, Playa Grande and Playa Langosta, Costa Rica. U.S. nesting is restricted to Florida with some nesting along the Mexican Gulf of Mexico.

 Habitat: they are pelagic, which means they spend most of their time in deep ocean.

Range: they have the widest range and can be found in all tropical and subtropical oceans. As far north as Canada, and as far south as New Zealand.

Migration: over 10,000 miles in search of jellyfish

Dive depth: an estimated 4,265 feet

Dive time: can dive up to 85 minutes at at time

 

Nesting Information

A leatherback sea turtle lays her eggs. Hilary Frandsen photo.

A leatherback sea turtle lays her eggs. Hilary Frandsen photo.

Like most sea turtles, it is a nocturnal nester. It is also the most marine of all the sea turtles and has great difficulty hauling ashore to nest. Like other species of sea turtles, the leatherback is unable to back up. If it cannot push through beach debris, it will overheat and die in the heat of the sun the following day. New World nesting occurs primarily during the month of December. Most females nest each year and produce six to seven clutches at 10 day intervals. In Pacific Mexico, the average is three nests per female with a clutch size of 50. However, in other areas, clutch sizes from 100 to 180 eggs are recorded. The incubation period varies between 50 to 55 days.

 Sexual maturity: around 16 years old

Primary nesting locations: Pacific Coast of Mexico at Barra de la Cruz, Chacahua, Oaxaca, Mexiquillo, Michoacan, and at Tierra Colorado, Guerrero, Playa Grande and Playa Langosta, Costa Rica.

U.S. nesting is restricted to Florida with some nesting along the Mexican Gulf of Mexico.

Nesting season: in the U.S., March to July

Nest size: about 50, and a female can lay three nests a season

Nesting time: at night

Egg incubation: 50 to 55 days

Current Threats and Historic Reasons for Decline

Newly hatched leatherbacks emerge from their nest and head to the ocean. Hilary Frandsen photo.

Newly hatched leatherbacks emerge from their nest and head to the ocean. Hilary Frandsen photo.

Longline fishing is the biggest threat to Leatherback populations. The type of hooks currently used, called "J Hooks" are accidentally catching and subsequently drowning thousands of leatherbacks. A new hook called a "Circle Hook" is currently being tested and implemented within many of the longline fisheries. This new style of hook catches tuna and swordfish (the desired catch) but not sea turtles.

Other major threats to leatherback populations are the accidental consumption or entanglement with plastics and discarded nets and line. Historically, the seasonal harvest of millions of eggs and the slaughter of thousands of nesting turtles has brought this species to its endangered status.