Since 2000, World Turtle Day has been celebrated on May 23rd with the intent to call attention to these remarkable shelled reptiles, and to raise awareness of efforts designed to protect turtles and tortoises and ensure their longevity. So let’s take a moment on this WTD to reflect upon these fascinating creatures.
The word “turtle” usually refers to any animal in the order Testudines, which contains reptiles that have evolved a specialized shell to protects their bodies. The shell is formed from modified ribs and backbones, and hasn’t changed very much since the first turtles showed up during the Triassic Period over 200 million years ago. Today, there are 14 families of “chelonians” (a fancy scientific word for turtles), containing over 250 living species. Generally, turtles are divided into three groups:
- Freshwater turtles (sometimes referred to as “terrapins”), which live near bodies of fresh or brackish water. They are not fully aquatic and spend some of their time on land.
- Sea turtles, which inhabit marine environments and have converted their feet into specialized flippers. They spend almost their entire lives in the ocean, only coming on land to lay their eggs.
- Tortoises, which live on land and do not swim. They tend to have more rounded, higher-backed shells than other turtles, and are usually found in the Testudinidae family.
|Desert Tortoise, a Land-dwelling Turtle||Red-Eared Slider, a Freshwater Turtle||Loggerhead Turtle, a Sea Turtle|
Most turtles can retract their heads into their shells for added protection, but the method for doing so is not always the same. Some retract their neck straight inward, while others must tuck their head to the side. Prehistoric ancestors of modern turtles could not retract their heads at all, and while some of those ancient turtles had teeth, modern chelonians possess toothless hooked beaks.
The largest turtle living today is the leatherback sea turtle, which can reach almost seven feet long and weigh nearly 1,500 lbs. The largest land turtle is the giant Galapagos tortoise, which can be over six feet long and weigh around 1,000 lbs. Galapagos tortoises have some of the longest lifespans in the animal kingdom, reaching over 100 years in the wild. Captive tortoises can live even longer...up to 150 years in some cases!
|Leatherback Turtle||Giant Galapagos Tortoise|
While some turtles are in no imminent danger of extinction, others are not so lucky. The red-eared slider is very widespread and plentiful, but it has become an invasive species outside of its native range and actually threatens other turtle populations. On the other end of the spectrum, the Kemp’s ridley sea turtle is critically endangered due to over-hunting, habitat loss, oil spills, and becoming tangled in fishing and shrimping nets. Other species, such as the loggerhead and leatherback sea turtles, are vulnerable and need help from conservation efforts to keep their numbers sustainable. The long-lived Galapagos tortoise mentioned previously is also facing threats: there were once up to 15 different species of this giant beast, but now there are only 12. All are vulnerable. Lonesome George, a captive Pinta giant tortoise, was thought to be the very last of his species when he died in 2012. He was believed to be nearly 100 years old.
|Loggerhead Turtle||Kemp's Ridley Sea Turtle||Giant Tortoise|
Turtles, terrapins, sea turtles, tortoises, chelonians – call them what you will, there’s no disputing that these unique animals are incredible creatures, worthy of our respect and protection. So today, remember our armored amigos, the turtles!
Bernie’s Bonus Fun Fact: The smallest turtle species is the speckled padloper tortoise, which grows to just three inches long.