The World's Most Endangered Freshwater Turtles and Tortoises

May 23, 2014 5:45 AM EDT

Is there anything more harmless than a turtle? (Unless, I suppose, you’re a nice, leafy vegetable.) Turtles and tortoises—the main difference is that turtles dwell at least partially in water, while tortoises live exclusively on land—are slow-moving, peaceful animals whose main form of protection from the outside world is a hard shell. Not for nothing do we have the fable of the slow and steady tortoise winning the race. Turtles have existed in some form for more than 220 million years, outlasting their early contemporaries the dinosaurs. Long-lived turtles and tortoises are symbols of perseverance in the natural world.

Unfortunately, the rules of the race are changing. Turtles and tortoises are among the world’s most endangered vertebrates, with about half their more than 300 species threatened with extinction. Only primates—human beings expected—are at greater risk of being wiped off the planet. The threats are many. The animals are collected by traders, eaten in the wild and in fine restaurants, used as pets or for traditional medicine, and sometimes simply killed. The very adaptations that once made them so successful—their long adult life span and delayed sexual maturity—has made them vulnerable as the world around them changed, mostly thanks to human beings. Climate change threatens them as well—a recent study found that as the water warms, more and more sea turtle hatchlings are being born male, which could eventually make it impossible for the species to reproduce successfully.

A 2011 report from the Turtle Conservation Coalition makes it clear: we need to act now if we’re to save the turtles and the tortoises:

We are facing a turtle survival crisis unprecedented in its severity and risk. Humans are the problem, and must therefore also be the solution. Without concerted conservation action, many of the world’s turtles and tortoises will become extinct within the next few decades. It is now up to us to prevent the loss of these remarkable, unique jewels of evolution.

As we mark World Turtle Day on May 23, spare a thought for these armored but endangered creatures.

The Mary River turtle is found in Australia, and is relatively tiny. It's endangered, thanks in part to the pet trade—it's also known as the Pet Shop turtle.Jason Edwards—National Geographic/Getty Images

The small Indochinese box turtle is found throughout Southeast Asia, but it's hardly abundant. Like a number of its relatives, the box turtle is critically endangered.Joel Sartore—National Geographic/Getty Images

Radiated Tortoise — The radiated tortoise of Madagascar is so named for the pattern on its shell. They are now critically endangered.Cyril Ruoso—JH Editorial/Minden Pictures/Corbis

The Coahuilan box turtle is found in Mexico. It's endangered, which puts it in better stead than many other turtles and tortoises.George Grall—National Geographic/Getty Images

Heosemys depressa, Arakan forest turtle — A very rare and endangered Heosemys depressa, also known as an Arakan forest turtle, is seen in New York. This is one of more than 1,000 endangered turtles that were saved from a loft in the city. Collectors are one of the biggest threats to endangered turtles and tortoises.Reuters

Worker from Rome's Biopark zoo holds a Testudo Kleinmanni hatchling in Rome — A worker in a zoo holds a tiny Testudo Kleinmanni hatchling. The endangered species is also known as the Egyptian tortoise, and was rescued from the suitcase of a smuggler found in Rome.Tony Gentile—Reuters/Corbis

The Sulawesi forest turtle is critically endangered, with just a handful of turtles left living in its wild habitat of Indonesia.Joel Sartore—National Geographic/Getty Images

Southern river terrapin — A 75-lb (34-kg) southern river terrapin waddles on sand as it is released near the Sre Ambel river in Cambodia. There are less than 200 of these turtles left in the wild. This one has a transmitter that will allow conservationists to track it.Eleanor Briggs—AP

A Madagascar big-headed turtle, Erymnochlys madagascariensis. Madagascar is home to more unique species than any other land mass of its size. But that also puts Madagascar tortoises under greater threat.Joel Sartore—National Geographic/Getty Images

A Burmese Star tortoise climbs out of its shell at the Taipei Zoo. The tortoise is the first of its kind to be born in captivity. Burmese Stars are under heavy pressure from poachers, going for $2,000 on the black market.Taipei Zoo/Reuters

The Plowshare Angonoka tortoise is found in the forests of Madagascar, where it is under heavy pressure from habitat destruction.Getty Images

Lonesome George, Pinta Island Tortoise — Known as Lonesome George, this Pinta Island Tortoise in the Galapagos was the last known member of his subspecies. Before his death on June 24 last year he was a symbol for conservation efforts.Tui De Roy—Minden Pictures/Corbis

The World’s Most Endangered Freshwater Turtles and Tortoises

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