These turtles are huge – they can be up to 1.5m long and over 180kg. They are one of the largest species of sea turtles. Their habitats traverse many different oceans and have exceptional navigation skills to return to the same grasslands that they have done for thousands of years.

The Green Sea Turtle (Chelonia mydas) is a keystone species (OCR). This means it plays a vital role in the food web and its presence in healthy population numbers is necessary for ecological stability. They were hunted for their beautiful shells and their meat was used to make turtle soup. Their eggs were a favourite human food so dug up and taken out of nests. This caused their populations to seriously decrease.

International Union for Conservation of Nature (IUCN) has a list of all the species globally that are under threat. The green sea turtle was on the brink of extinction and was listed as endangered but is now in the category of least concern. The organisation works in the field to calculate their population size. You will be familiar with the mark, release, recapture technique for estimating the population size of a mobile organism like the green sea turtle (AQA / OCR).

Global conservation needs to have a coordinated response to be successful and can take a long time – these green sea turtles were first listed as endangered in the 1980s. The aim of conservation is to stabilise populations and even, like with the green sea turtles – to restore populations. Success only comes when the conservation includes their natural habitats as well as their ecological role. And it’s not just the turtles that need healthy unpolluted oceans and coasts – we do too!

Conservation is an active process that needs careful management. In the case of the green sea turtle, patrols were set up to protect eggs being stolen from their nests and an education programme was put into place so that the fish catchers didn’t catch them in error and people understood that enjoying them and their eggs as food was destroying their populations.

As always, more needs to be done. Their numbers haven’t returned to their previous level before they were hunted. And now with the constant threat of habitat destruction through climate change and pollution, this work must be intensified. We have an ethical responsibility to protect our world’s species because once gone, they will be gone forever with untold consequences for us all.

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