All about sea turtles

There are seven sea turtle species in total.  We work in the nesting areas of three species; loggerheads, greens and leatherbacks.  Read on to learn more about these species and the threats they face.

Loggerhead turtle (Caretta caretta)


Named because of their large heads, the loggerhead turtle plays a vital role in keeping the ocean floor healthy.  Their powerful jaws crush up hard shelled prey such as clams and sea urchins and in this way recycle important nutrients, keeping the ocean floor in balance.

The shells of loggerheads are themselves a biologically important habitat.  A single loggerhead turtle may carry more than 100 species of small plants and animals on its shell!

Loggerhead turtles are classified as Endangered on the IUCN Red List of Threatened Species.  This is the second most severe category and means the species is likely to become extinct.  Sea turtles need to come back to land only to lay their eggs.   Many beaches used for nesting are being developed, particularly for tourism.  Light pollution, physical alteration of the beach and increased human activity make it increasingly hard for the loggerheads to nest.

Green turtle (Chelonia mydas)


The green turtle is unique as it is the only herbivorous sea turtle; it grazes on sea grasses and algae.   Sea grasses are nurseries for many fish and invertebrates.  Green turtles help to keep them healthy by grazing them and recycling nutrients back to the sea bed.

Green turtles are the only  species of turtles that will come to shore to bask, all other species only come to land in order to lay eggs.  They can be seen basking in only a few regions, including the Galapagos Islands and Hawaii.

The green turtle is classed as Endangered on the IUCN Red List of Threatened Species.  The major threat faced by green turtles is egg collection and the hunting of turtles for meat.  Hundreds of thousands of eggs are collected for eating and use in traditional medicines, and in one region of Mexico alone over 30,000 adult green turtles are poached every year.

Leatherback turtle (Dermochelys coriacea)


Leatherback turtles are named after their unusual leathery shell.   These are the most widely distributed of all the sea turtles; they travel to tropical waters to breed and temperate regions to feed.  Leatherbacks are known to cross the Atlantic and Pacific Oceans, but have also been spotted in the subarctic seas of Alaska and the freezing waters of southern Argentina.

The largest sea turtle ever found was a leatherback – a 3m giant of 914kg! The longest recorded ocean migration was also a leatherback, who travelled  12,774 miles in 647 days from Papua, Indonesia to Oregon, USA.  They are also the deepest diving sea turtle and can hold their breath for 85 minutes while diving up to 1200m!

As a species these record  breaking ocean wanderers are classified as Vulnerable by the IUCN, but the Pacific population is infact the most endangered marine turtle population in the world.    Hundreds of thousands of sea turtles get entangled in fishing gear every year as they make their way across the oceans. Long line hooks and shrimp trawl nets drown the trapped turtles as they are unable to make it to the surface to breathe.

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