Tortoises are land reptiles that can’t swim. This might seem odd since turtles can swim and look similar to tortoises, but the two species fundamentally differ in their habitats, physiology, and evolution.
Tortoises can’t swim because they lack webbed feet, and their legs aren’t shaped so that they can paddle. Their feet are suited to carrying weight and walking long distances, not swimming. Their shells grow heavier as they age, with layered scutes significantly weighing them down in the water.
Tortoises have evolved to spend their lives on land. So, they lack adaptations that give them any advantages in water, let alone an instinct for swimming. Most tortoises can’t paddle, tread water, or float.
Do Any Tortoises Swim?
Most tortoise species can’t swim because they lack the streamlined body parts turtles use to swim.
Almost all tortoises are strictly land reptiles. Although they enjoy soaking in water and may enter small puddles, they don’t swim or tread water in any way. Most tortoises can’t even float.
However, the leopard tortoise can float and paddle its legs. This is considered swimming, although it’s not an effective method and the leopard tortoise moves very slowly in water.
Furthermore, leopard tortoises can hold their breath, which allows them to remain submerged for up to 10 minutes, after which they can exit.
Why Can Turtles Swim But Not Tortoises?
Turtles and tortoises are reptiles with a similar appearance. Many people use “tortoise” and “turtle” interchangeably, believing the terms are based on semantics.
To some extent, this is true because tortoises and turtles belong to the testudine group. However, in practical terms, turtles and tortoises are very different animals with different physiology.
A turtle has evolved to live half or most of its life in water, while a tortoise must stay on land. A tortoise can’t adapt to spend more time in the water, or to swim, because it lacks a turtle’s unique body parts.
The two creatures live in vastly different environments, so tortoises would have no reason to adapt.
Webbed Feet
The main reason that turtles can swim, but not tortoises, is they have webbed feet. Only sea turtles have true flippers, whereas all other turtles don’t.
Instead, their stubby feet and claws have skin strips connecting the “toes,” which helps them propel through the water efficiently.
Meanwhile, tortoises have large, sturdy, bent legs with clawed toes.
There are no strips of skin in between, and they’re often compared to stubby elephant feet. A tortoise’s legs are much better-suited to land travel than traversing through the water.
This stubby design is meant to lift the tortoise’s heavy, shelled body off the ground as it moves around. It works for crossing large stretches of land and moving around on uneven terrains. A tortoise’s legs and feet are unsuitable for swimming.
Even leopard tortoises, which can float, aren’t good swimmers. Their stubby legs don’t create enough drag through the water, and they lack the skill to guide themselves, which makes swimming slow and aimless.
Shell Shapes
A tortoise is kept on land due to its shell design and weight. Turtles have light, flat, and streamlined shells designed for travel through water.
A tortoise has a heavy, dome-shaped shell with bony external plates called scutes. As the tortoise grows, new scutes grow from underneath the old ones.
Tortoises shed their scutes, but only in thin layers. So, their shells grow higher and get heavier with age, which causes larger species of tortoise to appear bulky at their full size.
Tortoises are intended to be slow due to their weight, which is why the large Galapagos tortoise will always move slower than a tiny Egyptian tortoise.
Galapagos tortoises have a difficult enough time moving around on land with heavy shells, let alone swimming. If a heavy tortoise tried to swim, it would sink and drown, not stay afloat.
Habitats
Turtles and tortoises live in vastly different environments, so each animal is adapted to suit its habitat in the most effective way possible.
According to the University of Arizona, the desert tortoise is a dry land reptile that lives in an arid region. Water is scarce, so it spends its entire life in soil and sand.
So, it’s developed a robust digestive system that gleans as much water from its food as possible.
Its skin and scales repel the sun’s excess radiation and handle the dry, scorching temperatures. Its feet are well suited to traveling across rocky terrain and digging through the hard earth.
None of these features are well-suited to living in water or swimming because it’s unnecessary. So, the desert tortoise can’t swim, even if it ever had the chance.
Since turtles spend their lives in aquatic environments, they’ve adapted to this environment. Not only are their webbed feet and shells hydro-dynamic, but they can hold their breath for an extended period.
Can Tortoises Breathe Underwater?
Tortoises can’t breathe water because they don’t have gills. At best, they can hold their breath, with some species performing this task better than others.
Tortoises can tolerate carbon dioxide because they must empty their lungs before entering their shells to hide. So, you’ll often hear a tortoise exhale when it’s startled and wants to tuck itself away.
As mentioned, the leopard tortoise can hold its breath for up to 10 minutes. This ability has saved many tortoises from danger, allowing them to stay concealed in their shells for longer.
It’s also enabled leopard tortoises to survive while struggling to reach land, should they be submerged and begin floating. It also protected tortoises mistaken as turtles and left in the water.
Do Tortoises Float in Water?
Some tortoises can float, including the leopard tortoise. According to the Journal of Herpetology, some tortoises can drift with their heads out of the water.
However, not all tortoises can do so because it depends on their age and weight. Some experts speculate that it is to do with the stillness of the water.
Lighter species of tortoises can float much better than heavier species. Young and energetic tortoises also float better because they don’t have heavy and bulky shells.
If the water conditions are right and the water is still, the tortoise may stay above water. It’ll struggle to move and paddle and bump into a shore. If it can’t, or the water becomes choppy, it’s likely to sink.
Do Tortoises Like to Swim?
Most wild tortoises dislike swimming and avoid water.
Tortoises instinctively know they won’t be able to tread water and get back to land.
However, tortoises enjoy soaking in shallow water that’s beneath their jawline. However, all soaks must be supervised in case your tortoise gets into difficulty and drowns.
Can Tortoises Drown?
Most tortoises will drown in water, especially if the water is choppy and exceeds head height.
If even one factor is off, this can lead to almost instant drowning. So, never leave an unsupervised tortoise around water that could entirely submerge it.
Can Baby Tortoises Swim?
Baby tortoises can’t swim, but you’ll find them living near bodies of water.
They need water to drink and bathe. However, if you were to put a baby tortoise into the water or accidentally fell in, it would almost certainly drown.
Baby tortoises aren’t very big, which means they have tiny lungs.
Although a baby tortoise is more likely to float due to its diminutive size, it’s also more likely to die once submerged. A lack of strength would also prevent it from safely paddling to shore.