Every other Friday on Morning Edition, Outside/In host Sam Evans-Brown tackles a question from a listener.
Claudia Asks: “What is the difference between a turtle and a tortoise? Which do we have in New Hampshire? Could you give some examples of each please?”
Editor's Note: This edition of Ask Sam first aired in April, 2020.
This is one of the classic turtle questions, and as such we’re going to knock it out of the park quickly and pivot to some #turtlefacts.
While all tortoises are turtles, not all turtles are tortoises. The main difference between the two categories is where they spend their time. “Tortoises tend to be much more terrestrial, so they spend a lot more time on land than our other turtles,” says Jennifer Moore from Grand Valley State University in Michigan.
“You know if you’re a tortoise who lives out in the dessert and lives out in the desert and all of the sudden you come across a watering hole… ‘Ooh! Lucky me, I might not see water for another six months or whatever,’” she says, “They’ll go sit in water, but they’re not out swimming in lakes.”
If you put a turtle and a tortoise side-by-side, the turtle would tend to have a more streamlined shell — better for swimming — whereas tortoises tend to have taller, more domelike shells. And Tharusha Wijewardena, a PhD candidate at Laurentian University in Ontario, says you see it in their feet, too. “Turtles usually have webbed feet with long claws, which help them swim and tortoises usually have feet that are short and sturdy because they are meant for walking.”
Turtle Facts Time
Ok, now for the real reason you all tuned in.
Aside from perhaps the greenland shark, turtles are the longest lived vertebrates on the planet. The oldest that we know of claimed to be 255-years-old, though certainly the saddest wikipedia page I’ve ever read is that of Tu’i Malila (King Malila), a radiated tortoise turned out to be a lady at the end of her difficult 188 years.
The suspected reason for their long lifespan is their incredibly slow metabolism. They can live for weeks without water, and years without food. A pet tortoise in Brazil survived in a shed for 30 years after its owners accidentally left it there. (Though it probably found things to eat in there)
They also undergo periods of dormancy. Tortoises mostly come from dry parts of the world so they do this during droughts. “If there’s like a super duper dry period, they can just go dormant and wait it out,” says Moore.
And around here turtles spend the entire winter under water without ever taking a breath. How? “So one of the things they can do is they can breath through their cloaca,” says Wijewardena, which dear reader, is kind of like their butt.
So, we might not have those incredibly long-lived tortoises around here, but arguably our turtles can do things that are much cooler.
In the last Ask Sam I recommended backyard birding as a low-risk way to get outside during a pandemic, but have you considered the simpler and more straightforward cousin: Herping? After all, there are a lot of birds to learn, but you'd only have to figure out how to identify seven turtles!
Sam Evans-Brown, is host of NHPR’s Outside/In which you can subscribe to where-ever you get your podcasts. If you’d like to submit a question you can record it as a voice memo on your smartphone and send it to email@example.com, OR call the hotline, 1-844-GO-OTTER, OR submit it here.