How Strong Is A Tortoise Shell?
fact checked & review by
Dr. Partho Kumar Shaha
Veterinarian (DVM)
The information is current and up-to-date in accordance with the latest veterinarian research.
There is a myth that tortoise shells are indestructible. Well, is that true? If not, how strong is a tortoise shell?
A tortoise shell can carry 200x of its weight. So again, if you want to bend the shell, you have to put 165.1 MPa force, and to crack it, you have to spend 56.4 MPa.
What happens if you put more pressure on the tortoise? Will it crack? Even if it breaks, does the tortoise’s shell heal alone? Find out your answers below.
How Strong Is A Tortoise Shell?
A tortoise shell can handle 200x of its own weight, which is 250 – 500 lbs for medium tortoises. The strength spikes up to thousands for the giant tortoises like Aldabra or Sulcata tortoises.
But why do you think tortoise shells are so strong?
Well, the species has evolved over the millions of years and has finally come to this shape. A hard and resilient carapace and plastron ensure the safety of the tortoises on land areas from predators. Also, the shell acts as a protection layer for the internal organs or other damages.
If you look into the physiology and structure of tortoise shells, you will get the mystery behind their strength.
A tortoise shell is not just a hollow board. It is more like an interconnection among the bones, scales, and muscles.
The joints here resemble trusses we imply on structural buildings or bridges to make them stronger and sustainable. In addition, a keratin layer on the bones enhances the protection and boosts resilience.
Nevertheless, tortoise shells are strong. There is no doubt about it. But remember, these carapaces or plastrons are not indestructible. Therefore, the pets will suffer from pain if the shells get damaged.
Is A Tortoise Shell Bulletproof?
Tortoise shells are not bulletproof. However, considering the speed of a bullet (600 – 5000 ft/s), it can impart 100 – 3300 ft/lb force on a tortoise shell. This force is enough to penetrate a tortoise carapace or plastron and do the damage.
Distributing a huge load evenly on a large scale has always been a hack. But when you pinpoint a position and apply all the pressure on that dot, it will crack for sure.
See, the bullet hits a small area on the tortoise scutes, and imparts all its energy on that particular point. So, for example, the fastest bullet comes to the surface and exerts a force of about 3000 lb per foot.
Tortoise shells are firm but not strong enough to withstand this much pressure. As a result, the bullet will break the scute and enter the tortoise’s body.
Just beneath the scutes, tortoises have bones and muscles. Hitting the muscle will make them bleed and will damage their nerves. Again, imparting the pressure on the bones can cause a crack.
In most cases, tortoises will survive a bullet. As the shell absorbs most of the pressure, the internal organs, muscles, and bones do not get damaged much. Yet, a complete body check-up is mandatory.
Now that the shell has a hole and crack, it is vital to bandage and take other actions to heal that part. Exposed cavities will invite parasites, bacteria, or fungus to live there, causing shell rot.
Different treatments are available to heal tortoise shell cracks. For example, filling the cavity with resin or epoxies is a better idea. Yet, consult a vet before executing any of your plans.
The Best Place To Buy Pet Tortoise!
Are you planning to get a pet tortoise? Or want to have in the future?
Today, I am going to introduce you with XYZReptiles.com, the store that sells their pet animals with LIVE ARRIVAL GUARANTEE. Here are the perks of getting tortoises from XYZReptiles:
- You’ll get a 100% Live Arrival Guarantee on all of their animals.
- They also guarantee the sex of the animal to match what they stated at the time of purchasing.
- The tortoises are in perfect size for getting into their new home! Not too large or a baby either!
- If you can’t pay the full price, no worries! You can make the payment in 4 interest-free parts with PayPal!
Check out their large tortoise collection here!
Can A Tortoise Shell Break?
Unfortunately, a tortoise shell can break despite how strong it is. Usually, tortoises can withstand pressure 200 times their weight. However, if their shell gets hit by a heavier force, it will break.
Tortoises experience cracked shells because of the following incidents,
- A fall from the height
- Running into a car
- Pyramiding
- Dehydration
- Insufficient UV rays
- Previous scratch, etc.
A broken shell leads to unbearable pain for the tortoises. You will notice the pets become dull, lazy, inactive, etc. It is because the sick tortoises spend all their energies on healing the cracklings.
It is not ideal for a tortoise to roam around with a broken shell. Such habits increase the risk of bacterial or fungal attack and further damage.
Again, if the shell is broken into pieces, the chips can get stuck into the internal organs. Also, sometimes, the force is so immense that it breaks inner bones and damages the muscles.
In any case, you have to take the necessary steps to heal the tortoise shell as soon as possible.
How Much Hard Is Tortoise Shell?
If you calculate the fracture resistance, it is somewhere around 36.4 MPa m1/2. So it means a tortoise shell is so hard that it can withstand 36.4 MPa pressure before crack propagation.
Per the general rules, a tortoise can carry weights 200 times heavier than its body. So, for example, a small tortoise with 2 – 5 lbs weight can hold 250 – 500 pounds of pressure. Again, the number will reach a thousand for medium and giant tortoises.
However, the shells are not always this hard. When born, tortoise shells are soft and weak. The scutes will stay that way if the creatures do not get enough nutrition and UV rays. Also, insufficient UVs will hamper their overall growth and lead to metabolic bone diseases.
Hence, if you want your tortoise to have a strong and hard shell, you should focus on the diet and UV sources.
How Protective Is A Tortoise Shell?
A tortoise shell is 100% protective against predators and any minor accidents. The keratin layer on the outside and bone structure on the inside make the scutes harder. Thus, it becomes impossible for any animal to penetrate their teeth or do any damage.
Shells protect tortoises in many ways, mentally and physically.
You know tortoises can retract their bodies inside a shell. Apart from shielding themselves from danger, tortoises also hide in their shell whenever they feel mentally drained. It is their way of cutting off the outside world and taking some time off.
Again, tortoises are creatures of the land.
Though they do not prey on animals, they are a lucrative snack for many predators. So shells come into the picture to save themselves from the predators.
Tortoises are not good at running or swimming. So they can only retract their bodies into the shell and wait for the predator to pass.
Most predators, no matter how strong, can not penetrate or break tortoise shells. Yes, they can scratch or may do minor damage, but the tortoise will still be alive.
What Tortoise Has The Hardest Shell?
Honestly, each tortoise is harder and stronger to endure heavy weight or impact. Sources say that the tortoise shell is stronger than aluminum. So, you can not differentiate tortoise shells based on their toughness.
But yes, the shells of all tortoises are not the same. For example, babies are born with a soft shell.
It grows harder and stronger with nutrition, calcium, vitamin D3, and UV rays absorption. The shells will develop weaker without these factors and will be easier to crack.
Again, dehydration is another factor that makes the shells flaky. Consequently, the shells get scratched or stretched and exposed to bacterial infection.
Overfeeding the tortoise also influences the unhealthy growth of the shells. To eliminate any of these conditions, you must take care of its shell.
How Much Force Can A Tortoise Shell Withstand?
A tortoise can withstand a weight 200x times heavier than its own. It means the creature can carry 250 to thousands of pounds on its shell, depending on its size. Also, the flexural strength and fracture toughness of tortoise shells are 165.1 MPa and 36. MPa, respectively.
Tortoise shells can do this magic due to their complex microstructure and structural design. The scutes consist of organic and inorganic films and fibers.
Also, a layer of keratin is on the top, which is found on human nails and animal horns. That also adds strength to the tortoise shell.
In another sense, a tortoise shell can ensure more force than an aluminum metal but less than a titanium metal.
Can Tortoises Live Without A Shell?
Tortoises can not live without their shell. In fact, the carapace and plastron have individual roles in a tortoise’s life.
The shells are not something these creatures can slip on and off whenever they want. Instead, the scutes and plates are fused and connected to the bones and rib cage of the tortoises.
Shells protect and shield the tortoises from the outer world and any predators. People think this is an extension of the tortoises, but no. Tortoises can feel the shells and any pain related to the scutes.
What Happens When You Put Weight On Tortoise Shell?
Tortoise shells carry immense loads and weight. Unfortunately, some people try to figure out the truth by experimenting.
I have seen videos of people attempting to ride a tortoise. Let me clarify one thing. It is animal cruelty and just not fair.
A tortoise shell is hard and strong, protecting them only when needed. They are not for carrying weights or taking loads 24/7.
Loading the tortoise shells will make the tortoises suffer. The creatures will have damaged legs and limbs because of the constant weight.
Also, they will experience breathing issues. You know tortoises do not have powerful lungs like us. So making these creatures work will leave them breathless.
Moreover, the tortoises get affected by mental stress. Your fun moment can make these creatures insecure and stressed. As a result, they will start acting abnormally, stop eating, and might even die.
Can A Tortoise Shell Heal Itself?
Luckily, a tortoise shell can heal itself. So any crack or scratch, nature will heal everything.
Generally, it takes 2 – 3 weeks for the underlying soft tissues to heal, whereas the minor cracks can heal over 4 – 18 months. However, the major fractures take years, sometimes decades, to heal.
But as you know, keeping the tortoise in an open shell is not advisable. It entices bacterial and fungal attacks, which make the tortoises suffer. So you have to take the tortoise to the vet for treatment.
There are different ways and methods of fixing a broken shell. A bandage to prevent air or moisture from entering will work in case of scratches. For punctures and holes, you must fill up the cavity with bio-compatible resins.
Conclusion
Tortoise shells are stronger and harder than most other things around you. But it does not mean you should put weights on the tortoise. No. Making the tortoises carry weight makes them suffer.
Again, tortoise shells are stronger but not indestructible. A significant impact can even crack the shell open. Take immediate action if you notice any abnormality on the carapace or plastron. Otherwise, there will be shell rot or bacterial attack.
About Author
Muntaseer Rahman started keeping pet turtles back in 2013. He also owns the largest Turtle & Tortoise Facebook community in Bangladesh. These days he is mostly active on Facebook.