Tortoises are accomplished at digging, using a scratch-dig method that has served them well for thousands of years. So, tortoises will burrow underground if their enclosure bedding is deep enough.
Tortoises burrow underground for survival, comfort, and fun. Baby tortoises are most likely to bury themselves as they’re more vulnerable to predation (easier to pick up, softer shells, etc.)
Burrowing enables tortoises to hide when afraid, brumate during cold weather, avoid overheating on hot days, and lay clutches of eggs.
Tortoises burrow deep into the ground, creating tunnels at around a 45-degree angle. If an enclosure has a foundation, the tortoise might burrow as far as it can or up against the corners.
How Deep Do Tortoises Burrow?
Tortoises use a scratch-digging motion to create a slight incline, leading to stable burrows. According to Historical Biology, tortoises are used as a reference to deduce how ancient dinosaurs dug burrows.
On occasion, tortoises burrow up to 50 feet into the ground.
The tunnel may be shallow if tortoises want a burrow to keep them cool during the summer. This is usually 2-3 feet into the ground or just enough to cover the tortoise’s shell.
Getting well below the frost line is necessary if the tortoise needs to brumate. This tunnel may be 5-6 feet deep.
Nesting holes go no more than a few inches into the ground.
Tortoise tunnels are different from mammalian burrows. While mammals dig down steeply, tortoises will burrow at a gentle slope (around 45 degrees), enabling these accomplished climbers to go in and out with minimal difficulty.
How Do Tortoises Breathe Underground?
If a tortoise has gone underground for an extended period, it won’t suffocate. Tortoises are skilled at building tunnel walls with loose dirt and a semi-clear path back to the surface.
This allows oxygen to pass through the walls and arrive through the entrance. So, tortoises can remain underground for as long as is required while breathing easily.
Why Do Tortoises Bury Themselves?
All tortoises have the instinct to burrow as there are physical and emotional benefits.
Your tortoise might dig underground for the following reasons:
1/ Predators And Feeling Threatened
If a tortoise fears a predator or threat is nearby, it’ll enter self-preservation mode, retreating deep into its burrow. Digging underground provides a means of protection, enabling tortoises to avoid detection by predators.
Burrowing is common during the first few days of owning a tortoise. Until it grows comfortable in its enclosure and feels safe around you, a tortoise will hide underground to feel safe.
2/ Fun And Enrichment
Tortoises find burrowing fun and entertaining.
So, you may find tortoises digging holes that they don’t live in or ever explore. They may even burrow underground for a few minutes or hours, emerging in good spirits.
3/ Extreme Temperatures
Tortoises rely on their living environment to regulate their temperature. Tortoises will enter their burrows to reduce or raise their temperature when the weather is particularly hot or cold.
Brumation During Cold Weather
Once the temperature dips below 45-50 degrees Fahrenheit, conditions will be too cold for tortoises.
Brumation is instinctual for tortoises when the weather is cold. It involves burrowing underground, staying out of sight, and conserving energy.
Instead of a deep sleep, tortoises will awaken at times, becoming active if the need arises. Examples include repositioning themselves and drinking water.
Brumation enables tortoises to remain warm, as reptiles are ectothermic. Tortoises don’t produce body heat, relying on direct sunlight and other heat sources, such as heat lamps.
Brumating tortoises will go into their burrows and emerge 2-3 months later when the weather is warmer. While most tortoises brumate, such as the leopard tortoise, there are exceptions.
Hot Weather
Once the temperature exceeds 95-100 degrees Fahrenheit, conditions will be too hot for tortoises.
Excessive heat can lead to sickness in tortoises, such as heatstroke and dehydration. Finding a shaded area or burrowing into the ground creates a cool, sheltered place to avoid overly hot temperatures.
For example, the desert tortoise is known to dig deep into the ground to escape the sweltering desert temperatures, emerging in the late afternoon or evening when temperatures drop.
4/ Nesting
If you’ve wondered, “do tortoises bury their eggs?” they do.
Tortoises bury their eggs so that they can hatch away from the prying eyes of predators. Before laying her eggs, expect female tortoises to start excavating.
Nesting holes aren’t the same as burrows, which are holes that serve multiple purposes, such as offering shelter and temperature control. Meanwhile, nesting holes are places to lay eggs so they can hatch more safely.
Females don’t lay their eggs in burrows but may lay them next to the burrow entrance if no alternative is available. Additionally, while burrows can be deep, nesting holes are shallower.
Once eggs are laid, tortoises cover the nesting hole and walk over, trample, and camouflage them. Using the underside of the shell, they’ll seek to remove any signs of anything buried there.
This protects the eggs against curious predators that might dig up the nest and feed on the eggs. Once the eggs hatch, tortoises don’t look after their young.
Why Does My Tortoise Dig In The Corner?
It’s normal to find a tortoise burrowing, so you may see a tortoise digging in unusual places. You can determine a tortoise’s intentions or concerns based on its position.
Digging Into Corners
If a tortoise is digging in the corners of its enclosure, the bedding isn’t deep or firm enough to dig a tunnel. So, your tortoise may be trying to use the enclosure wall as part of the tunnel.
Alternatively, the enclosure isn’t large enough, and the tortoise feels restless. This is usually accompanied by scratching at the enclosure walls and incessant digging.
If so, ensure that you have the right bedding, as this leads to sturdier tunnel walls that aren’t in danger of caving in and leaving them feeling vulnerable and afraid.
Digging Everywhere
Tortoises enjoy digging, so it’s common for them to dig many different burrows. Some tortoises will dig up to 35 different burrows.
When it’s time for tortoises to brumate, they dig up several patches of ground. These will face different directions and be in several locations around the territory.
This ensures that the tortoise has several hideouts, each with a slightly different temperature.
Digging Under Corners And Walls
Tortoises dig under walls and corners when expanding their territory, feeling unsafe in their enclosures, or attempting to escape. Beyond that, some tortoises are more curious than others and enjoy exploring.
Tortoises dig burrows for various reasons, ranging from enrichment to hiding from predators and threats. Digging is an activity that most tortoises, except leopard tortoises, are good at and enjoy.