Sea Turtles – Endangered Marine Life

August 25, 2008 / 13 Comments

sea turtles Sea Turtles   Endangered Marine Life

Categorized from threatened to critically endangered, sea turtles from the world’s oceans have mostly been hunted down for their meat, fat and shells (tortoiseshell). These days, the most significant threat for them is a commercial fishing technique called longline fishing, that uses hundreds or even thousands of baited hooks hanging from a single line and causes accidental sea turtle deaths.

There are seven living species of sea turtles and here’s a little bit on each of them.

Flatback Sea Turtle

flatback sea turtle Sea Turtles   Endangered Marine Life
Flatback Sea Turtle

Living in bays, shallow, grassy waters, coral reefs, estuaries and lagoons on the continental shelf of Australia, Indonesia or the coast of Papua New Guinea, the flatback turtle is a bit more unusual than its fellows because it lays less but larger eggs. Crab Island is the most significant breeding site in the western Torres Strait. Breeding may also occur on the islands of the southern Great Barrier Reef, and on mainland beaches and offshore islands north of Gladstone.

Locally this turtle is called “Kikila” and the species name is Natator depressus. It’s from Latin and means flat, referring to the carapace. It has great colors: yellow-grey or sometimes a green-grey carapace, pale yellow lower shell (plastron) and a yellow band underneath that outlines the marginal scutes. The flatback sea turtles adults can reach as much as 198 pounds (90 kilograms) and they measure up to 39 inches (100 centimeters) long.

Hawksbill Turtle

Hawksbill Sea Turtle
Hawksbill Sea Turtle

Eretmochelys imbricata or widely known as the hawksbill turtle it’s similar to other marine turtles but also has some characteristics none other have. It has a sharp, curving beak-like mouth with prominent tomium and a saw-like appearance of its shell margins, two pairs of prefrontal scales, thick posteriorly overlapping scutes on the carapace, four pairs of costal scutes and two claws on each flipper. Most appreciated meals consist of sea sponges, but rest assured they won’t say no to some comb jellies or jellyfish.

Hawksbill Sea Turtle
Hawksbill Sea Turtle

The hawksbill turtle has been declared a critically endangered species mostly because it was hunted for flesh (good eating) and the shell which is used as primary source for tortoise shell material. Found predominantly in tropical reefs of the Indian, Pacific and Atlantic, E. imbricata is the one most associated with tropical waters.

Some of the places where you could see the hawksbill turtles include the Gulf of Mexico, the Brazilian coast (specifically Bahia), southern Florida and Hawaii, on the beaches of Antigua and Barbuda, in Costa Rica (specifically close to Tortuguero), the Island of Cuba, in Puerto Rico near Mona Island, close to Cape of Good Hope in Africa, across the entire Indonesian archipelago, the Japanese archipelago, New Zealand and on the the northwestern coast of Australia.

In the Philippines, a small group of islands in the southwest of the archipelago have been named the “Turtle Islands” and I don’t think we should explain why.

Green Sea Turtle

Green Sea Turtle
Green Sea Turtle

The only species in the genus Chelonia, the green sea turtle lives in the tropical and subtropical seas around the world with main populations in the Atlantic and Eastern Pacific Oceans. Largest of all the hard-shelled sea turtles, they grow up to more than 3 feet (0.92m), weighing some 300-350 pounds (136 – 159 kg). The green sea turtles are unique among sea turtles because they’re herbivorous and feed primarily on sea-grass and algae, this being the main reason for the greenish fat underneath their shell.

Green Sea Turtle
Green Sea Turtle

In the Atlantic, the major nesting places for Chelonia mydas can be found on various islands in the Caribbean (Aves Island, the U.S. Virgin Islands, Puerto Rico and Costa Rica), on the eastern shores of the continental United States, the eastern coast of the South American continent and most notably, on isolated islands in the South Atlantic. Other great places are the island of Ascension, Florida Keys, Florida Bay, Homosassa, Crystal River and Cedar Key.

In the Pacific, best nesting places are in Mexico, the Hawaiian Islands, the South Pacific, the northern coast of Australia and Southeast Asia, on both sides of the Arabian Sea, both in Ash Sharqiyah, Oman, and along the coast of Karachi, Pakistan.

Loggerhead Sea Turtle

Loggerhead Sea Turtle
Loggerhead Sea Turtle

Known as Caretta caretta, which derives from the French caret – meaning turtle, the loggerhead sea turtle is the most common sea turtle to nest in the United States. It has large and powerful jaws to help crushing mollusks, crustaceans, fish, jellyfish, the Portuguese Man o’ War, hard-shelled prey such as whelks and conch. and other small- to medium-sized marine animals. Although they are very good swimmers, the loggerhead sea turtle has callus-like traction scales beneath their flippers that allows them to “walk” on the ocean floor.

Loggerhead Sea Turtle
Loggerhead Sea Turtle

Preferring high energy, relatively narrow, steeply sloped, coarse-grained beaches, the most important nests for loggerheads are in Turkey, Greece, Bonaire, Costa Rica, around the Italian islands of Lampedusa and Linosa, off the coast of Sicily, and in Calabria, where it is particularly endangered and on the beaches of the Northern part of Cyprus, especially Alagadi Beach. The biggest nesting beaches (with more than 10,000 females nesting per year) are in South Florida (U.S.) and Masirah Island (Oman).

Kemp’s Ridley Sea Turtle

Kemp’s Ridley Sea Turtle
Kemp’s Ridley Sea Turtle

Considered a critically endangered species, Kemp’s Ridley (or Lepidochelys kempii) is the smallest of all sea turtles, only growing a meter long and averaging not more than 45 kg (~100 lbs) as an adult. Over the course of years they change the dark gray-black color as hatchlings into yellow-green or white plastron when they mature. A favorite meal for Kemp’s Ridley turtle, always includes crab.

Where can you see the Kemp’s Ridley sea turtles? In the Atlantic Ocean and the Gulf of Mexico. They’re “inhabitants” in places like New Jersey or Florida, and most females lay their eggs on the Rancho Nuevo Beach in the Mexican state of Tamaulipas.

Olive Ridley (Pacific Ridley) Sea Turtle

Pacific Ridley Sea Turtle
Olive Ridley (Pacific Ridley) Sea Turtle

In Spanish they call it tortuga golfina o del golfo and the species name is Lepidochelys olivacea. It’s one of the smallest sea turtles out there, growing up to 50kg big (~110 lbs) that is called that way because its heart-shaped shell has the color of the olives. The favorite meal for these omnivorous little fellows include crabs, shrimp, rock lobsters, sea grasses, algae, snails, fish, sessile, pelagic tunocates and small invertebrates.

Olive Ridley Sea Turtle
Olive Ridley (Pacific Ridley) Sea Turtle

Considered vulnerable by the US Endangered Species Act, they can still be found in the Indian Ocean in Orissa, in the Atlantic and the Pacific Ocean or the Red Sea (particularly in Eritrea where they actually hatch). Other places where the Olive Ridley turtle can be found is the Bay of Bengal close to Tamil Nadu coastline and on the shore of Saint Martin’s Island in Bangladesh.

Leatherback sea turtle

The only living species in the genus Dermochelys, the leatherback turtle is the largest and heaviest of all sea turtles and is considered the fourth largest reptile, behind the larger crocodiles. Unlike its ‘sisters’ it doesn’t have a bony shell. It’s covered by thick skin and oily flesh, instead of carapace. Adults average from 1m to 2m large and weigh from 250kg to 700kg, but the largest leatherback turtle went easily over 900kg.

Of all sea turtles, Dermochelys coriacea has the widest distribution being found in all tropical and subtropical oceans, reaching from Alaska and Norway to Cape Cod in Africa and far away to the southernmost point in New Zealand. The places where you’ll most likely get to see the leatherback turtle are in Suriname and French Guiana in the Caribbean and Gabon in Central Africa.

Images courtesy of 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11