Why Do Tortoises Burrow Underground: Understanding This Complex Behavior
Tortoises are fascinating animals. With a metabolic function that operates quite differently from our own and that of other warm-blooded species, it can be hard to figure out why tortoises do what they do.
Take burrowing, for example. Many new keepers don’t realize tortoises even have the ability to create their own burrows by digging and moving things around to suit their needs.
Pet tortoises often get temporarily “lost” this way until the owner figures out that their tortoise has dug a burrow and crawled inside!
In this article, we will talk about why tortoises burrow underground and what purpose this interesting behavior serves for different tortoise species.
Why Do Tortoises Burrow Underground
Tortoises burrow underground for a variety of smart reasons. Burrowing can create micro-climates to escape extreme heat or cold. Burrows offers safety and shelter. Burrows can create more secure hiding places for a tortoise to lay eggs.
And burrows can help the tortoise to wait out natural disasters like wildfires and the unwanted attention of predators.
We will discuss even more reasons why tortoises burrow underground in the remainder of this article.
This fantastic YouTube video featuring the legendary Sir David Attenborough gives you a glimpse into the burrowing habits of one particular tortoise species, the Gopher tortoise.
As you can easily see, tortoise burrows serve multiple purposes – and not just for the tortoises!
Is a Tortoise Burrow the Same As a Tortoise Hole or Nest
As Crazy Critters nonprofit rescue explains, not every underground shelter your tortoise uses may be a burrow.
Your tortoise’s age, life stage, gender, and husbandry needs dictate what type of structure your animal may seek out, including burrows, holes, or nests.
A tortoise burrow is the type of shelter we are primarily discussing in this article.
Tortoise burrows, unlike holes or nests, can actually extend for many feet underground.
Tortoises, like the Gopher tortoise you watched in the YouTube video in an earlier section here, have powerful front legs. They use their legs to dig out burrows and often share these burrows with other animals.
Burrows allow tortoises to safely move about from place to place. A single tortoise may create multiple burrows in the area where they live.
Only female tortoises will create nests. The tortoise nest has one purpose: to provide sanctuary to eggs.
Tortoises do not incubate their eggs as birds do. The female will create the nest, lay eggs, cover the eggs back up and move on, never to return.
Tortoise Trust highlights one little-known fact that surprises many first-time keepers. Female tortoises, like chickens and other birds, can lay unfertilized eggs once they reach sexual maturity.
Tortoise nests typically are more shallow and much less complex than tortoise burrows.
A tortoise hole provides the tortoise with some shelter and protection from the elements. Tortoises may dig holes after rain to hydrate and wallow in the mud.
Tortoise holes can also provide some protection and defense against insects.
While a tortoise burrow will completely hide the tortoise from view, a tortoise hole may only cover part of the tortoise.
What Motivates Tortoises to Burrow Underground
As the popular Tortoise Forum owner site explains, some tortoise species are more likely to dig burrows than are other species.
But when a tortoise digs a burrow, the motivations are pretty similar across species.
Hatchling tortoises dig burrows for protection
However, most hatchling tortoise species will instinctively seek out the shelter of a burrow or hole to hide in to avoid predation.
Hatchling tortoises typically need to hide to feel safe and secure and this behavior can persist throughout the first few years of life.
Tortoises dig burrows to escape extreme weather
Tortoise species that naturally live in more extreme climates, such as arid/desert species where temperatures get very hot during the day and quite cold at night, will dig burrows to create microclimates.
As Tortoise Trust explains, a tortoise’s burrow microclimate is like a little underground oasis where the animal can self-regulate body temperature and guard against dehydration.
Tortoises dig burrows to brumate (hibernate)
The Tortoise Group points out that burrows can also serve an important function for brumating tortoise species.
Brumation is similar to hibernation but not exactly the same. Hibernation is a term that is generally reserved for warm-blooded animals that have a greater ability to self-regulate their body temperature and metabolic function.
In cold-blooded species such as tortoises, the correct term for this same process is brumation or torpor. It is a type of metabolic slowdown that helps tortoises stay alive during the winter when sunlight and food are less available.
Tortoises will burrow up to half a foot below the ground surface to brumate when daylight hours shorten and temperatures decrease. They will stay there until the ground begins to warm up for the spring.
Tortoises dig burrows to escape predation
Because tortoises are slow-moving and defend themselves with difficulty against potential predators, many tortoises will use burrows as a primary form of self-defense.
Some predator animals cannot or will not attempt to follow them into a burrow, giving the tortoise a way to escape.
Tortoises dig burrows to escape predation
As Tortoise Tracks explains, tortoises also dig burrows at times to try to collect rainwater.
These shallow depressions or holes offer the tortoise a way to access the water and drink it.
Do Tortoises Store Food in Burrows
This brings up an interesting question about whether tortoises also store food in their burrows to guard against lean times.
Tortoises have not been observed to store or stockpile food in their burrows the way many warm-blooded foraging and scavenging species will do.
However, tortoises do use their own bodies to store water. Tortoises often have multiple water bladders inside their bodies where they can store water against arid weather conditions.
When the tortoise gets dehydrated because water is scarce in the environment, their body can access and reabsorb the stored water in their bladders.
What Should You Do If Your Tortoise Burrows Underground
Burrowing can serve many important functions for a tortoise.
However, the function it serves for your particular tortoise absolutely depends on the tortoise species you are caring for.
The best approach is to learn and study everything you can find about your particular tortoise species.
You will want to learn whether your tortoise needs to hibernate or not (this can also depend on the age and life stage of your animal).
If you are caring for a female tortoise, you may observe some burrowing behavior as she gets ready to lay eggs (fertilized or unfertilized).
Creating microclimates is one of the most essential functions of tortoise burrowing behavior. Each tortoise species has different temperature, heat, and humidity needs.
Your tortoise species may burrow to try to create a more comfortable and suitable microclimate to stay healthy.
It is not uncommon for pet tortoises to burrow without their owners knowing and suddenly disappear!
If this happens with your pet tortoise, you can examine their enclosure to look for telltale signs of digging or the displacement of rocks, grass, or turf.
The more you learn about your particular tortoise species, the more your pet’s burrowing habits and behaviors will start to make sense. This is especially vital if you are caring for a female tortoise or a brumating tortoise species.