14 Jun 2017 Story Ocean & Coasts

Turtle teaser: Fast facts about some of the world’s most ancient species

How long have sea turtles been around?

Sea turtles have been around since dinosaurs roamed the earth, more than 100 million years! They’re air-breathing reptiles who inhabit tropical and subtropical ocean waters throughout the world. Some species are able to withstand enormous pressure as they dive up to 900 metres into the ocean.

Where do they lay their eggs?

Sea turtles nest on thousands of beaches in dozens of countries around the world. Most of their lives are spent at sea. They return to the shore to lay eggs, often making long journeys to go to specific beaches year after year. One species (Pacific loggerheads) migrates over 7,500 miles between nesting beaches in Japan and feeding grounds off the coast of Mexico.

The temperature of the sand determines the gender of the sea turtle, with cooler sand producing more males and warmer sand producing more females. Depending on the species, they may lay up to 250 eggs in one nest; the eggs take around 60 days to incubate.

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Photo Credit: S.G. Dunbar/ProTECTOR Inc.

 

What are the main threats facing sea turtles?

Sea turtles face many human-related threats, including entanglement in fishing gear, ocean plastic, coastal habitat destruction, poaching of adults and eggs, and climate change.

Current research suggests warming trends due to climate change may cause a higher ratio of female sea turtles, potentially affecting genetic diversity in the future.

How many species are there?

There are seven species of sea turtle: Loggerhead, Green, Leatherback, Hawksbill, Olive Ridley, Kemp's Ridley and Flatback. Six of the seven species are considered endangered or vulnerable by the International Union for the Conservation of Nature. Two species (Hawksbill and Kemp’s Ridley) are considered critically endangered.

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Photo Credit: S.G. Dunbar/ProTECTOR Inc.



 

What do they eat?

Sea turtles are omnivorous. Adult green turtles are the only marine turtles to exclusively eat plants. Hawksbill turtles in the Caribbean eat a lot of sponges.

The diet of a sea turtle depends on the species. Most of them will eat jellyfish, though the Leatherback is the only species to eat them exclusively. Each day, a Leatherback – which can weigh up to 900 kg – can eat its own weight in jellyfish. Hawksbills focus on sea sponges, eating up to 1,000 per year, which helps coral reefs grow since they compete with sponges for space. Loggerheads eat primarily crustaceans like lobsters, urchins, and crabs.

Are there any agreements to protect them?

An intergovernmental agreement – concluded under the auspices of UN Environment – aims to protect, conserve, replenish and recover sea turtles and their habitats in the Indian Ocean and South-East Asian region. The agreement, which took effect in 2001, is called the Memorandum of Understanding on the Conservation and Management of Marine Turtles and their Habitats of the Indian Ocean and South-East Asia.

 

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Photo Credit: S.G. Dunbar/ProTECTOR Inc.

 

 

The Turtleshell Trade

The shell of the Hawksbill has been used to make different products for thousands of years. Known as “tortoiseshell”, these products have been especially popular in Japan, where they are known as “bekko”. From the 1950s to the 1990s, more than 2 million shells were shipped from around the world to Japan, where artisans would craft products for sale.

Despite being made illegal to trade internationally by the Convention on International Trade of Endangered Species (CITES), the sale and export of turtleshell products continues.

In Latin America, a recent report by the campaign group Too Rare To Wear documented more than 10,000 items for sale at more than 200 souvenir shops in eight countries around the region. These products can be found for sale across the tropics as well, including in Africa and Asia.

UN Environment encourages travellers to learn how to identify turtleshell products and avoid shopping for souvenirs at stores where they are sold.

Lewis Pugh is the United Nations Patron of the Oceans. Read his story, Turning turtle on the illicit wildlife trade.

Read this Q&A with renowned ocean expert Pierre-Yves Cousteau on his passion to protect sea turtles.

For further information: Lisa.Rolls[at]unep.org

Media enquiries: unepnewsdesk[at]unep.org

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