The information is current and up-to-date in accordance with the latest veterinarian research.
Newbies are not so familiar with the digging behavior of tortoises. They often think that there is something wrong with the pets. But is it true? If not, then why do tortoises try to dig the soil?
Tortoises dig because,
- The surface temperature is too hot or cold for the tortoise.
- Your pet is hiding underground to protect itself from external threats.
- The tortoise is stressed and looking for an escape.
- It is the brumation or nesting season for the tortoises.
- The pet is digging for fun.
Is digging healthy for the tortoises? Can you stop the pets from digging? Let’s find out.
6 Reasons Why Tortoises Dig Soil
Digging the soil is just another activity for the tortoises. But sometimes digging indicates a change in the tortoise or its surrounding. Here are 6 reasons why your tortoise actually digs,
1. A Way Of Controlling The Body Temperature
Tortoises are ectothermic or cold-blooded creatures. Therefore, environmental heat has a great significance in their life.
Tortoises search for heating sources to warm off their bodies in cold winters. These creatures tend to brumate when they fail to get any heat. Similarly, during the hot summer days, tortoises look for shades to release the heat.
Another way of warming up or cooling off is to burrow.
The temperature in the immediate subsurface of the soil is opposite of the surface. It means the underground is cool in the warm season. Likewise, in winter, the subsurface is warmer than the topsoil.
So, tortoises regulate their body temperature by digging in the soil.
Take the example of desert tortoises. These creatures dig holes in the sand. Staying inside the tunnel allows them to avoid the direct sun ray and minimize the heating of the shells.
On the contrary, the brumating tortoises burrow in the ground for warmth and safety.
In captivity, tortoises live in a controlled environment. Yet, the tortoises dig soil by instinct if the temperature becomes too hot or cold for them.
Tortoises dig a shallow burrow in the warmer season to cool off the temperature. The depth of the holes will be roughly between 2 – 3 feet.
In colder seasons, tortoises dig deep holes to brumate. The burrowing tunnel’s depth can be 5 – 8 feet.
2. Searching For A Secure Place
Tortoises have a shell to tuck inside when any threat comes. But as you know, shells can not help these reptiles fight all dangers. Hence, tortoises sometimes bury themselves underground to defend themselves from the hazard.
In the wild, tortoises burrow underground to protect themselves from foxes, coyotes, and other predators.
However, a captive habitat is always safe and secure for the tortoises. So, why do pet tortoises bury themselves under the substrates?
Well, the owners try their best to fence around the outdoor habitat or cover the indoor pen for security. Still, the glimpse of a barking dog or an aggressive cat is enough to scare the pets. The threatened tortoises then try digging the soil to eliminate the danger.
Again, as I say, tortoises are bullies. Housing multiple tortoises inside the same enclosure often make the stronger ones dominate the weak ones.
The scared pets, in such cases, look for hiding spots for safety. Getting inside a hole is an excellent escape for them.
Furthermore, tortoises also burrow when they are stressed. A loud noise or constant handling of these pets will make them insecure and threatened. Thus, they may feel the instinct to dig and get into the hole.
3. May Be The Tortoise Is Brumating
As mentioned, tortoises are cold-blooded creatures. Therefore, they need additional heating sources during the winter to stay warm. Tortoises will enter brumation if you fail to keep them warm.
Brumation is nothing but the hibernation of cold-blooded reptiles. In this state, the tortoises avoid eating and live on the previously stored energy.
Generally, tortoises are of slow metabolism. So, they require little energy to carry out their daily activities. The energy consumption level drops even more when they brumate.
Tortoises slow their heart rate and oxygen consumption and stop doing the routine. A brumating tortoise can pull this off for 3 months or more because they spend the period sleeping.
Of course, these reptiles can not brumate on flat ground. Instead, they require a hole for the period to hide from potential predators. Also, the place has to be in an uphill area so that water does not enter inside.
Tortoises prepare themselves and their surroundings for the brumation long before the winter arrives. Hence, you may notice the creatures looking for a suitable burrowing spot before the cold season.
They sniff the ground to get an idea of the soil’s strength, temperature, and moisture content. If everything is okay, the tortoises will start digging.
A 6 – 8 feet burrowing tunnel with 45 degrees steep is perfect for tortoises. The inclination helps these reptiles to get inside the hole with minimum hassle. However, depending on the species, the tunnel depth can be 50 feet.
4. Preparation For Nesting Season
Usually, tortoises nest during the months of May – July. If a gravid tortoise digs the soil, maybe it is time for nesting.
Tortoises require uphill, sun-facing, and perfectly moist soil to lay the eggs. Places with shades are not ideal nests as they can not retain heat. Similarly, a flat area is at risk of getting flooded.
These reptiles will go from place to place and scratch the soil to guess the properties. Tortoises can understand the temperature and humidity conditions of the ground by sniffing, head-scratching, and digging.
The creatures finally start digging the egg chamber when the soil satisfies all their needs.
An egg chamber is basically bell-shaped and several inches big. The tortoise digs the soil and gathers it on one side of the nest.
There is no exact depth of the tortoise nest, and it solely depends on the species size. The depth should be enough so that the gravid tortoise can feel the ground when its legs are fully stretched. Tortoise will lay the eggs at the entrance and pack the hole with the gathered soil.
Remember, tortoises do not lay eggs in the burrowing tunnel. Instead, they dig a nest with a smaller depth.
5. No Reason At All
Sometimes your tortoise digs for no valid reason. It will scratch the soil and burrow in just for the sake of fun. Well, it is natural, and there is no harm in it.
Tortoises dig the substrate when they feel bored. Even these creatures enjoy lying in the cool, damp soil. Moreover, digging also acts as a fun exercise for these reptiles and a way to fend off their stress.
6. Making An Escape Way
Tortoises are born curious. They will sniff and bite almost everything coming their way. So, if the pets realize the vastness outside the enclosure, they will try hard to escape.
For example, a transparent glass confuses the tortoises. These innocent creatures dig the substrate and scratch the walls to get out.
But curiosity is not always why a tortoise wants a way out of the pen. The tortoises behave restlessly if the temperature and surroundings get unbearable. Again, a starving tortoise also seeks an escape to search for food.
Can You Tell Tortoise Digging Behavior?
Of course, you can not guarantee why your tortoise is digging the soil restlessly. But reading the environment gives you a fair guess about the reason. Look at the 3 digging behavioral pattern tortoises shown below,
Tortoise Digging At The Corner
Such behavior can indicate,
- Tortoise wants to expand its territory.
- The pet is insecure and threatened in the pen. It wants to escape the habitat.
- Your tortoise is stressed.
- Only the corner portion has a mounding.
Tortoise Digging Everywhere
A tortoise has been reported to dig 35 burrows in a single season. Tortoises usually dig multiple holes during the nesting and brumating. They do this to find the perfect tunnel for the season.
How To Help The Tortoise Dig Safely?
As you know, tortoises are natural burrowers. So, you may catch your tortoises digging soil for no valid reason.
Therefore, experts suggest layering up the habitat with an appropriate substrate. Otherwise, the tortoises scratch the glass tank’s bare bottom and get nowhere. This will indeed stress the pets.
Here are some ideas to help the tortoises dig more satisfyingly,
Build A Burrowing Spot
We provide a substrate layer several inches thick in both indoor and outdoor enclosures. But as we have seen before, the burrowing tunnel of giant tortoises is several feet. So, the bottom substrate will not work as a burrow.
Hence, build a mound with moist and loose dirt or soil at one corner of the habitat. The height of this mound can be several inches to a foot. Do not increase the size, as the pet can fall from the top.
The mound should be protected from the outside so that the tortoise can not escape the pen.
Plan For Hides
Besides the big mound, you need to plan a few more hides in the enclosure for the tortoises. The soil of the hides should be several inches thick, moist, and loose. Tortoises may not use the spots to hide, but they will have fun digging them.
Take Your Tortoise Outside
Tortoises love open green fields. Of course, the area allows them to graze and dig at the same time.
You can let your tortoise walk and run in your backyard. Soon you will catch your pet digging the soft soil energetically.
Do not worry. The tortoise is not stressed or regulating the body’s warmth. But the pet is simply enjoying its time in nature.
How To Stop The Tortoises From Dig
Digging is very much natural for both wild and captive tortoises. They find it fun and stress-relieving to burrow underground. In fact, wild tortoises spend more than 70% of their lives underground.
But then again, not all digging is healthy. So, here is what you can do to cancel out the unwanted digging activities,
- Always maintain a proper temperature inside the tortoise habitat. Depending on the species, the air and basking temperature should be between 70 – 100 degrees Fahrenheit.
- Move your tortoise to an indoor setup during winter. An outdoor housing with a proper heating pad and sun-facing open space also works. Learn how to build a tortoise winter pen from this link.
- If you allow your tortoise to brumate, prepare the pet beforehand. Also, do not forget to provide several mounds to burrow.
- For gravid tortoises, offer proper substrate for nesting. A commercial nesting chamber also works for these pets. Find common questions on tortoise egg care in this write-up here.
- Make sure the tortoise enclosure is fenced and protected from predators. Also, the surroundings should be calm and noise free.
Before You Go
Building a mound and hiding spots is mandatory in the tortoise enclosure. Also, covering the bottom with a proper substrate is suggested. Go through the following article to find the best substrate for your tortoises.