Skip to Content

How long can red-eared sliders hold their breath?

The red-eared slider, a charming subspecies of the pond slider and arguably the most popular pet turtle, is a semi-aquatic reptile that flourishes in freshwater habitats. Known for their easy-going nature and minimal care requirements, these turtles spend a considerable amount of time submerged, showcasing their prowess as great swimmers.

The question of how long red-eared sliders can hold their breath is not just intriguing but reveals the fascinating biology of these creatures. Typically, a red-eared slider can conserve oxygen and energy, managing to hold its breath for 30 to 45 minutes.

However, during sleep or in states of brumation—the reptilian form of hibernation where metabolism dramatically slows down—they can remain underwater for several hours to many months, respectively. This incredible ability is largely due to their slow metabolic rate, regulated by the water temperature and the turtle’s body temperature, which affects their heart rate and oxygen consumption.

Moreover, their adaptability to varying water conditions, from clean to dirty water, and their capability to survive in both warm and cold water highlight their resilience and the complexity of their respiratory and muscle systems. In environments that mimic their natural habitat, providing a basking area is crucial for their good health, allowing them to regulate their body temperature and potentially reducing the energy expended underwater.

Today, we dive deeper into the world of red-eared sliders, exploring the duration they can spend under the surface and the physiological marvels that allow them to do so. We’ll also touch on the importance of maintaining optimal water conditions, the role of aquatic plants in their diet for those with a slow metabolism, and how these factors contribute to their longevity and quality of life. Whether they’re gracefully gliding through the water or basking in the warmth, understanding the nuanced life of red-eared sliders opens up a window into the intricate balance of aquatic life and survival strategies of semi-aquatic animals.

How long can red-eared sliders hold their breath? The answer lies in their fascinating biology and the environmental conditions they thrive in, and we’re here to uncover just that.

How Long Can A Red-Eared Slider Hold Its Breath?

A red-eared slider coming up for air
A red-eared slider coming up for air

Under the right conditions, the red-eared slider can hold its breath for several weeks and even months. Red-eared sliders are highly anoxia-tolerant, which simply means that they can tolerate water that has little or no dissolved oxygen in it, and it’s an adaption that helps them to survive chilly winters.

Red-eared sliders can survive in an environment with no oxygen for weeks or even longer. When submerged underwater, they can also rely on cloacal respiration to absorb oxygen — you read that right, red-eared sliders and many other aquatic turtles can breathe through their butts!

This is only possible if temperatures are low enough. Since turtles are cold-blooded and rely on outside temperatures to regulate their own body heat, they have a very low metabolic rate during winter when temperatures can fall below freezing.

Apart from the temperature of the pool where the turtle brumates, the size also matters. Larger ponds have more oxygen dissolved in the water. A small turtle tank won’t have enough oxygen to make cloacal respiration worth it.

Without cloacal respiration, the turtle will have to rely on anaerobic respiration – a special form of metabolism that doesn’t require oxygen – and this can keep the turtle going for several weeks.

Thus during cold winters when the red-eared slider is brumating, it can hold its breath for several days, weeks, or even months.

When temperatures are NOT near freezing, the turtle has to rely on normal aerobic respiration to live. During this time, the turtle requires a substantial amount of oxygen, and can only hold its breath for about 30 to 45 minutes before it needs to come up for air. 

When stressed or active, this number is lowered drastically, as the turtles metabolism is going about as fast as it can go. A stressed red-eared slider can hold its breath for about 10 minutes at most before it will need to come up for a quick breath of fresh air.

A sleeping red-eared slider can hold its breath and sleep underwater for up to 9 hours, but just as often they have another way to sleep that’s quite fascinating. They store air in their necks and this acts like a flotation device!

This air allows them to float near the water’s surface when sleeping so that they can also take advantage of trapped underwater air pockets or simply grab a fresh breath at the water’s surface before submerging themselves again.

How red-eared sliders respire

a red-eared slider in a tank
A red-eared slider can breathe through its nostrils…. and through its cloaca!

Turtles don’t have gills, they have lungs, and they typically breathe through their nostrils. The red-eared slider, however, can also respire cutaneously.

Cutaneous respiration is also known as skin breathing and it’s pretty much what it sounds like – gaseous exchange occurs across the skin rather than the lungs or gills.

With sliders, this gaseous exchange occurs through the cloaca, and this is called cloacal respiration. The cloaca is a cavity at the end of the turtle’s digestive tract that is used to excrete waste and in this way, it is the equivalent of the human anus. Cloacal respiration is commonly refired to as “butt breathing”.

The turtle also uses the cloaca for mating, but that’s another subject for another article!

Speaking of mating, did you know that a female turtle will lay eggs even without a mate? Better have a nesting box ready! Find out more when you’re done here in our DIY slider nesting box guide.

Breathing Air

The main way that a turtle respires is by breathing air through its ‘nares’, which are nostrils above the mouth.  Humans have flexible ribcages that expand and contract as we breathe, but turtles, including sliders, have rigid ribs.

The shell is even part of the ribs and because of this adaption, turtles have developed strong trunk muscles that expand and contract the lungs as the turtle breathes in and out.

Turtles including red-eared sliders breathe with their mouths closed and the pressure of the water actually helps sliders to breathe in and out.

Cloacal/Enteral Respiration

We’d touched on cloacal respiration — absorbing oxygen in the water through the cloaca — but this is worth a closer look to understand how it’s really done. It starts off with the turtle passing water through the cloaca. Bursae located in their cloaca are responsible for absorbing oxygen from the water.

This process, fascinating in its efficiency, involves the bursae (a sac-like organ) extracting oxygen directly from the water, a testament to the unique respiratory system of turtle species like the red-eared slider.

Cloaca respiration is typically inefficient, as the turtle absorbs very little oxygen this way, and this method of respiration cannot provide the turtle with enough oxygen to be healthy. As such the turtle still needs to come up to breathe air from time to time if it doesn’t wish to drown.

So what is the use of cloacal respiration? Sliders usually employ cloacal respiration when brumating during the winter. As turtles can be stuck under ice for months, it’s a solution that Nature has provided them to help them survive.

Even if the pond isn’t frozen, the cold temperatures mean that the turtle is extremely lethargic and doesn’t have the energy to swim up easily.

As turtles are cold-blooded, their metabolism is directly determined by the temperature of their environment. Their low metabolic rate during winter allows the turtle to survive on the tiny amount of oxygen absorbed during cloacal respiration.

While submerged and still, oxygen passively diffuses through the skin of the bursae located in the cloaca. Turtles brumating during the cold of winter can also respire anaerobically, which doesn’t require oxygen.

This anaerobic respiration is hard on the turtle, however, as It leads to a build-up of lactic acid which is bad for the chelonian’s muscles.

Anaerobic respiration

Red-eared slider coming out onto the land
With anaerobic respiration, turtles can generate small amounts of energy without oxygen!

Cellular respiration can be divided into two subcategories – These are aerobic respiration and anaerobic respiration.

With aerobic respiration, the cells rely on oxygen to break down sugar and produce energy. With anaerobic respiration, the energy is produced without oxygen. Anaerobic respiration isn’t efficient and there is also a buildup of lactic acid which is harmful to the body. What’s more, humans do it, too!

In humans and other mammals, anaerobic respiration causes painful muscle cramps, so it’s not something that we can rely on to help us survive for very long.

Red-eared sliders, on the other hand, are highly anoxia-tolerant. This means that they can rely solely on anaerobic respiration at very low temperatures, living for several weeks with no oxygen. During this period, they rely solely on glycogen reserves for energy.

The turtle’s shell also plays a major part in allowing the turtle to survive several weeks and months without oxygen. Calcium carbonate released from the shell buffers the lactate (the conjugate base of lactic acid), which in turn ensures that the heart doesn’t stop beating.

The heart beats at a low rate and circulates lactate, waste products, and nutrients.

Anaerobic respiration is only a viable method of respiration for several months when temperatures are low – 37.4 degrees Fahrenheit (3 degrees Celsius). When it’s warm, however, the turtle’s metabolism is simply too active to employ this winter survival strategy.

The capacity for anaerobic respiration in red-eared sliders, similar to that seen in leatherback sea turtles and loggerhead sea turtles, underscores the diverse survival strategies among different turtle species. These adaptations ensure survival in varying water conditions, from the oxygen-rich surfaces to the anoxic depths of their natural habitats.

If you’d like to learn more, Nature.com has an excellent article on turtles and their breathing techniques that you can read here!

About the Red-eared Slider

The red-eared slider (Trachemys scripta elegans) is a subspecies of the pond slider. These turtles are semiaquatic and can easily be identified by the red markings on their ears which give them their common name.

Endemic to the midwestern United States to Mexico., Sliders are highly adaptable and are considered an invasive species all over the globe. For this reason, it is important to NEVER release your pet red-eared slider into the wild.

The red-eared slider is moderately sized, reaching a carapace (shell) length of 6 to 8 inches, although some can reach a length of approximately 16 inches.

These freshwater turtles, also adapting to brackish water conditions, are known for their versatility and are found basking near water surfaces or diving into deep water for food or safety. They are also opportunistic feeders devour just about any plants and animals that they can fit in their mouths.

Frequently Asked Questions

Can red-eared sliders sleep underwater?

Not only can red-eared sliders sleep underwater, they also sleep exclusively underwater. Red-eared sliders like to rest at the bottom of their aquatic habitat or float near or on the water’s surface. When sleeping at the bottom of their habitat, they come up for air regularly as they need oxygen to live.

When floating on the water’s surface, they use their inflated throat to help them float as they sleep, making it easy to grab a breath of fresh air whenever they need it.

How do red-eared slider turtles breathe underwater?

Technically, sliders cannot breathe underwater, but they can absorb a small amount of oxygen through cloacal respiration. They do this by allowing water to pass over the bursae located in their cloaca – something turtle fans like to refer to as ‘butt breathing’.

This only allows them to absorb a minute amount of oxygen, so it’s only helpful during brumation in winter when the turtle’s metabolism is slowed down enough for the minimal oxygen to help give the turtle a chance to survive for longer than they could otherwise.

How long can a turtle hold its breath while sleeping?

Different turtles can hold their breath for different lengths of time when sleeping. For instance, sea turtles can hold their breath for up to 7 hours when sleeping, while a red-eared slider can hold their breath for up to 9 hours when asleep.

Wrapping up

For turtle owners, understanding the turtle’s need for a dry area, the importance of maintaining the right pH level and temperature of the water, and providing a heat lamp for their basking spot are essential for mimicking their natural habitat and ensuring their well-being. Adult turtles and baby turtles alike benefit from environments that cater to their semi-aquatic nature, requiring both land and water areas to thrive.

As an aquatic animal, the red-eared slider needs to be able to hold its breath for an extended period. In normal circumstances, sliders can hold their breath for 30 to 45 minutes at a time. When sleeping, they require less oxygen, and can hold their breath for up to 9 hours!

When brumating, which is the reptile form of hibernation, sliders can hold their breath for weeks or even months. During this time, their metabolic rate slows to a crawl, allowing them to respire with a very limited amount of oxygen which they absorb through cloacal respiration.

They can also live for several weeks without oxygen, as they are highly anoxia-tolerant, and really the only time that they can’t hold their breath for very long is when they are active and stressed. That reduces their underwater time to approximately 10 minutes.

When you consider that humans can only hold their breath for 3 to 5, then that 10 minutes is still a pretty impressive trick, all courtesy of turtle evolution and Mother Nature!

Are you considering bringing a slider home from the pet store, but not sure what it needs for a tank? We can help with red-eared slider tank setup!

Click to rate this post!
[Total: 0 Average: 0]

Sharing is caring!