I don’t know about you but before I owned a tortoise I didn’t think of them as the sort of animals that dug holes. To me they seemed too heavy and lumbering to do that, burrowing to me seemed strictly reserved for mother nature’s more nimble offspring.
My ignorance aside however, there is no denying that tortoises most certainly do like to burrow and dig. When you think about it their legs need to be pretty strong to carry those heavy shells around, so it stands to reason that they’d be adept at digging holes as well.
The reasons tortoises like to dig vary, but as you might have guessed they don’t do it purely for the fun of digging. Burrowing serves many purposes, from being a way to evade predators, to a forming the basis of a nest. In the wild tortoises can build large networks of tunnels, with some reaching depths/lengths of 10 metres/30’ or more.
As tortoise owners it’s of course our business to know why tortoises burrow so that we can be accomodating of it, given that it’s a natural and instinctive behaviour.
On the other hand if you live in a part of the world where you have wild tortoises living in or around your backyard, it might well be that you want to know how to prevent or discourage tortoises from digging holes all over your lawn!
Either way, read on!
Why do Tortoises Bury Themselves?
Shelter and Temperature Regulation
Just as one of our most basic needs is to have a roof over our heads, the same is obviously true for tortoises.
Whilst tortoises have a fairly reliable home in the form of their shell, being cold blooded means they need a little more help in order to regulate their temperature, particularly to help them stay warm.
One reason for building an entire network of tunnels is that it provides the tortoise with a greater temperature gradient so that he or she can select the right ambient temperature to suit their needs at any given time. So a colder tunnel is better for sleeping, while a warmer tunnel is the best place to head to after waking up for example.
The same principle of course rings true in your tortoise table at home- the reason for having the heat lamp at one end is to provide a clear temperature gradient from warm to cool.
Besides being an effective means of temperature regulation, and underground tunnel network also provides an effective retreat from rain, frost, snow, and even crippling heat from the sun.
An effective burrow is particularly important for wild tortoises during hibernation (brumation) because it keeps them out of the worst of the winter weather, whilst at the same time being cool enough to allow the tortoise to enter their hibernative state.
Protection Against Predators
Being the slow lumbering chaps they are means that tortoises are somewhat vulnerable to predators such as birds of prey, foxes, and other adversaries. A well constructed, sufficiently deep enough burrow provides an effective deterrent against the worst of these predators.
Just as a burrow protects the tortoise itself against predators, it also provides a safe and secure environment for a female tortoise to lay her eggs.
How do Tortoises Burrow?
If you look at the front legs of most tortoise species you’ll notice they’re disproportionately large in the ‘forearm’ a bit like Popeye! This gives them the strength they need to carve out the impressive burrows they’re known for.
You’ll also notice that their legs are covered in large plate like scales, which have developed to protect against the impact from abrasive soil and stones.
Strong fork like claws tear into the soil to complete the physiological ensemble, making tortoises perfectly adapted to their burrowing habits.
Does a Tortoise in Captivity Need to Burrow?
Given that we know tortoises burrow in order to regulate their temperature and protect themselves against predators you would think the obvious answer to this question would be a resounding ‘no’.
Well whilst it’s probably true that as an owner you’ll be providing all the necessary infrastructure needed for your tortoise, making the need to burrow redundant, keep in mind that they don’t have the intelligence to comprehend this fact.
Therefore it would be cruel to deny your tortoise the opportunity to burrow, so you should provide provision for it.
With an indoor enclosure provide a decent depth of substrate in your tortoise table or vivarium, ideally with a nice loose substrate that’s easy for the tortoise to move out of the way.
Outdoors can be a bit more tricky as you don’t necessarily want to encourage your tortoise to burrow their way out of their enclosure! To prevent this I suggest having an area of additional soil (preferably sterilised) that is deliberately deep and loose to encourage any digging to take place there where it can be done safely.
How Can I Stop My Tortoise From Digging?
If for any reason you want to prevent your tortoise from digging in a certain area, the simple solution is to make it difficult or impossible for them to do so!
As mentioned above if you can provide a safe area right in the middle of your outdoor enclosure that’s safe and easy to burrow, this should deter the tortoise from burrowing elsewhere, such as towards the edge of the enclosure.
Burrowing near to the edge of the enclosure there is (in theory) a chance that the tortoise could escape, or more dangerously perhaps, that the tortoise makes the job of a fox trying to burrow its way into the enclosure slightly easier having done some of the heavy lifting already.
If you want to make burrowing near the edge of the enclosure more difficult, you could always install a wooden internal perimeter floorboard of say 200mm (8”) around the internal edge of the enclosure, such that the tortoise is unable to start burrowing right at the edge of the enclosure. This will give you plenty of time to see what he or she is up to, and take action to fill in any holes if necessary.
Gopher Tortoise Burrowing Under House
If you live in the southeast United States, in particular Florida, you might well be privy to a very particular kind of natural phenomena.
The Gopher Tortoise (also known as a Desert Tortoise) is a protected species that makes its home in the sandy, herbaceous habitats of this region, and is considered a vital component in the local ecosystem.
The reason for this is that Gopher tortoises are rather handy at digging tunnels, more so than other breeds, and many other creatures from frogs to small mammals and birds take refuge, or make their homes in these tunnels.
Is it Possible to Get Rid of a Gopher Tortoise?
It’s because their impact on the health of the ecosystem as a whole is so great that Gopher tortoises are protected, and therefore it is illegal to try and banish, or even discourage them from leaving your property if your yard is home to one.
The general advice for Floridians is to leave Gopher tortoises well alone, and that, as long as their burrows pose no immediate threat to structures such as housing foundations then there probably isn’t anything to be concerned about.
For anyone that is concerned about what impact Gopher tortoises are having on their property, it is possible to apply for a ‘Relocation Permit’ from the Florida Fish and Wildlife Conservation Commission, if they are able to prove the presence of the tortoise or tortoises is of genuine concern.
Even then however, ‘relocation’ in this context only means that the tortoise can be relocated to another spot on the same property, so it’s debatable how effective having one of these permits can actually be.