The differences between turtles and tortoises allow us to better appreciate and understand chelonians. Turtles can be categorized into three broad types.
These include sea turtles, freshwater turtles, and land tortoises. When the word turtle is heard or read, what comes to mind are sea turtles and freshwater turtles.
Scientifically speaking, even tortoises are turtles. Turtles are reptiles that belong to the order Testudines. This order contains as many as 300 species.
That means there are about 300 different kinds of turtles in the world, of different sizes, shapes, and colors. In this article, we will explore the differences between sea turtles, freshwater turtles, and tortoises.
Turtle and tortoise differences are highlighted when you know where to look. We will also touch on difference between turtles and terrapins and answer the question – “What exactly are terrapins?”
Turtle and Tortoise Differences
Table of Contents
|1. Physical Appearance|
|2. Distribution and Habitat|
|5. Key Turtle and Tortoise Differences|
|6. What Is a Terrapin?|
1. Physical Appearance
First of all, we have to look at the appearance of each type of turtle as this is usually the easiest to spot. The differences in physical characteristics can help you to quickly tell turtles and tortoises apart.
The easiest way to differentiate turtles from tortoises is by inspecting their limbs.
Tortoises have short elephantine legs that bend at the knees. As such, when they move, they walk on their toes/claws. The back end of their feet usually doesn’t touch the ground. Tortoises have small limbs in comparison to their bodies. These limbs along with their legs and necks have loose, pliable skin which allows them to retract into their shells when threatened.
Freshwater turtles generally have webbed feet (except box turtles which don’t have webbed feet). Webbed feet help turtles to swim. They also have long claws. All freshwater turtles (including box turtles) have flat feet. When they walk, their entire feet touch the ground.
Sea turtles have front and back flippers instead of feet. Flippers make sea turtles very recognizable. While they are very slow on land as the flippers aren’t made for walking They are very fast in water where they use the flippers as paddles to speed along. Unless they have to lay eggs, sea turtles remain in the ocean.
Both turtles and tortoises can pull their necks and heads into their shells. This is a clever defense adaptation that they use when threatened. Their tough shells protect them from harm. Additionally, with their limbs and head tucked in, they look like large rocks to both predators and preys alike.
There are two ways the turtle can tuck its neck and head into the body. It can pull the neck straight into the head as most turtles do or move the head and neck sideways into the shell as most sideneck turtles do (an example of a sideneck turtle is the African mud turtle also known as the African sideneck turtle).
Both turtles and tortoises have tails. While you can’t differentiate a turtle from a tortoise by inspecting the tail, you can generally tell the sex of the turtle from the tail. More often than not, male of a species have thicker and longer tails than the females of the same species.
You can use the shape and appearance of the shell to differentiate a turtle from a tortoise.
Most turtles’ shells are more streamlined, lighter and flatter. As aquatic creatures, the streamlined nature of the shell allows them to swim faster. Sea turtles have excellently streamlined shells. Sea turtles, however, cannot hide inside their shells as other turtles do.
Tortoise shells are high domed, rounded and heavy. Since they are slow, their heavy armored shells to protect them from predators. As tortoises don’t swim and aren’t aquatic, the weight of the shell is not a problem. Tortoises and freshwater turtles can retrieve into their shell when threatened.
The shell is made of bones (about 50 in total) and consists of the carapace (upper part) – this forms their dome, and the plastron (lower part) – this covers their underside.
The carapace and the plastron are connected by a bridge to form their shell. On top of the shell are scutes. These are made of keratin and are, consequently, hard.
These scutes help protect the bony shell. Old scutes are shed and replaced with new ones as the turtle grows. Adult turtles still shed their scutes as this keeps the shell disease-free.
Not all turtles have scutes. Softshell turtles have tough skin over their shell instead of scutes. As such, their carapaces look leathery and feel soft. Some popular turtle species that don’t have scutes include the spiny softshell turtle, the black softshell turtle, the African softshell turtle, and the Florida softshell turtle.
In summary, while turtles have more streamlined shells to help them swim better, tortoises’ shells are generally bulkier, high domed, and heavy.
2. Distribution and Habitat
As you may already know by now. Difference in habitats is one of the easiest ways to tell turtles and tortoises apart.
Tortoises are land creatures, and as such, they live on land. They may bath and cool off in pools and streams or even drink from them, but they don’t live in water and will drown in a deep enough water body as they cannot swim.
Africa and Europe (in particular the Mediterranean) have the largest tortoise populations. Tortoises are found in
- Asia, examples include the Asian giant tortoise (Manouria emys), the Elongated tortoise (Indotestudo elongata), and the Indian Star Tortoise (Geochelone elegans),
- Africa, an example includes the African spurred tortoise (Centrochelys sulcata) also known as the Sulcata tortoise,
- the Mediterranean European countries, examples include the Marginated tortoise (Testudo marginata), and the Greek tortoise (Testudo graeca),
- and the Americas, an example is the Red-footed tortoise (Chelonoidis carbonarius).
The box turtle of North America looks a lot like a tortoise and is often confused for one. However, they are pond turtles. Tortoises can be found in arid regions, forests, near lakes, swamps, and even lagoons.
Turtles, unlike, tortoises are very common in North America. They can also be found in Africa, Europe, and Asia. Since turtles are aquatic or semi-aquatic, if they are found on land, expect a water body close by.
This water feature can be a pond, stream, marshland, river, lake or even the ocean. Most North American turtles also hibernate (or to be more accurate brumate).
As they are cold-blooded, being active during the cold seasons is impossible. To survive, they find a warm spot (usually a burrow) to hide and brumate through the winter. Once outside temperatures rise again, they come out and resume their life.
Popular turtle species found in –
- North America include the red-eared slider (Trachemys scripta elegans), eastern box turtle (Terrapene carolina carolina), common snapping turtle (Chelydra serpentina), and the false map turtle (Graptemys pseudogeographica).
- Africa include African softshell turtle (Trionyx triunguis), African mud turtle (Pelusios castaneus), and the African helmeted turtle (Pelomedusa subrufa).
- Asia include the Chinese box turtle (Cuora flavomarginata), the Japanese pond turtle (Mauremys japonica), the Chinese softshell turtle (Pelodiscus sinensis).
- Europe include European pond turtle (Emys orbicularis), Western Caspian turtle (Mauremys rivulata), and Sicilian pond turtle (Emys trinacris).
Turtles are generally omnivorous. Some such as the softshell turtles (for example the black softshell turtle) tend to be primarily carnivorous, while others such as the adult black sea turtle tend to be primarily herbivorous.
However, they are generally omnivorous. They tend to eat insects such as earthworms, crickets (diy cricket farm guide here), and mealworms. They also eat aquatic creatures such as aquatic insects, mollusks, crabs, clams, shrimps, crayfish, snails, frogs, and fish.
Plant matter turtles eat include hyacinths, pear cacti, duckweed, hibiscus leaves and flowers, water weeds, algae, green pepper, collard greens, spinach, and romaine lettuce. They also eat fruits such as melon, banana, strawberries, dandelion, mulberries, and apples.
Tortoises, on the other hand, are almost always herbivores. They generally eat the plant matter available in their natural habitat. As such, tortoises that are endemic to shrublands, and arid areas generally feed on succulents, cacti, leaves, and stems. While tortoises in forested areas feed on grass, weeds, fruits, and berries.
When kept as pets, tortoises accept grass, hay, weeds, dandelions, hibiscus leaves and flowers, succulents such as aloe vera, pear cacti, collard greens, romaine lettuce, and fruits such as melon, apples, and strawberries.
When kept as pets, both turtles and tortoises need calcium supplements. Those kept indoors need both vitamin D and calcium supplements. Without these supplements, they grow to have severely deformed shells.
While this is an unsightly appearance, it is also harmful to their health. Calcium and vitamin D deficiency can even lead to death. Sprinkle calcium powder on the food fed captive turtles.
Turtles housed outdoors utilizes sunlight to synthesize vitamin D3 so don’t need vitamin D3 supplement. You need to supplement the diet of turtles kept indoors with vitamin D3 (and calcium), even if UVB lights are present in their indoor enclosures.
Lifespan is another way to differentiate turtles from tortoises.
Freshwater turtles generally live to be 20 to 40 years depending on the species.
Sea turtles live longer than freshwater turtles with a lifespan of 60 to 70 years.
Tortoises have the longest lifespan of all chelonians with an average lifespan of 60 to 80 years. Several tortoise species such as the Galápagos tortoise (Chelonoidis nigra) and the Aldabra giant tortoise (Aldabrachelys gigantea) can live to be over 100 years. The average lifespan of most tortoise species is longer than that of Homo sapiens (humans).
To keep a tortoise or turtle as a pet, you must be committed. You can’t decide after 10 years that you no longer want to care for your pet tortoise or turtle. Some tortoises may even outlive their keepers. If you can no longer care for a chelonian, ensure that it is relocated to a good home.
5. Key Turtle and Tortoise Differences
Here is a summary of the key differences.
- Turtles are generally aquatic and semi-aquatic reptiles, while tortoises are primarily terrestrial reptiles.
- Turtles have light shells so they can swim quickly and efficiently, while tortoises have heavy shells to offer maximum protection from predators.
- Turtles are flat-footed and have either flippers or webbed feet (except for box turtles). This helps them swim. Alternatively, tortoises have clawed elephantine feet (and walk on their toes).
- Turtles have lifespans of 20 to 40 years (60 to 70 for sea turtles), while tortoises have lifespans of 80 to 150 years.
6. What Is a Terrapin?
The term terrapin is used to refer to a group of freshwater turtles (mostly North American) that are capable of living comfortably in brackish water as well as freshwater. These terrapins are usually small turtles with adult lengths of 3 to 7 inches.
What’s the difference between a turtle and a terrapin? While turtles generally refer to all freshwater turtles and sea turtles (to an extent even tortoises), terrapins refer to a group of small aquatic turtles that are generally native to North America (some terrapins are not native to North America).
There are several differences between turtles and tortoises. Differences include physical appearance, habitat, distribution, and diet. When you know what to look for, it is easy to tell a tortoise and a turtle apart.
However, if you don’t know what to look for, differentiating between the two can be quite tough. If you have any knowledge or expertise when it comes to telling chelonians apart kindly leave a comment. Similarly, if you have any questions, kindly leave a comment. Thanks.