Like many other chelonians, Hermann’s tortoises (Testudo hermanni) can make excellent pets. But in order to keep your tortoise healthy, you need to provide him with the proper environmental conditions – especially as it relates to the temperature and humidity level inside the habitat.
In this article, I’ll be outlining the proper temperatures and humidity levels for Hermann’s tortoises and share some tips for achieving the ideal conditions. But first, it’s important to learn a little about the natural habitat of these tortoises.
Natural Habitat & Climate Conditions
Hermann’s tortoises – like most other pet reptiles – will thrive best when provided with environmental conditions that reflect those they experience in the wild. Fortunately, Hermann’s tortoises experience a broadly similar climate across their range, which makes this easier than for some other species.
Hermann’s tortoises are native to a large portion of southern Europe, stretching from Turkey and Greece in the east, up through the Balkans, around the coast of Italy, and west as far as the southern coast of France and Spain. This entire region experiences a Mediterranean or “dry summer” climate.
Areas with a Mediterranean climate typically experience warm to hot summers during which relatively little rain falls, and cool to mild winters, when the bulk of the annual precipitation occurs. The exact climatic conditions vary across this range, so for context, here below is an overview of three European cities within the range of the Hermann’s tortoise.
Climate of Athens, Greece
Athens’ climate is pretty typical for a place that experiences a Mediterranean climate. December is the wettest month, while August is the warmest.
- July temperatures typically fall between 76- and 93-degrees Fahrenheit
- January temperatures typically fall between 44- and 57-degrees Fahrenheit
- July precipitation averages 0.26 inches
- January precipitation averages 2.04 inches
- Humidity levels in July average 41%
- Humidity levels in January average 68%
Climate of Rome, Italy
Rome also has a fairly normal Mediterranean climate, though the rains peak in November. August is the hottest month, while January is the coldest.
- July temperatures typically fall between 67- and 89-degrees Fahrenheit
- January temperatures typically fall between 37- and 55-degrees Fahrenheit
- July precipitation averages 1.01 inches
- January precipitation averages 1.9 inches
- Humidity levels in July average 55%
- Humidity levels in January average 74%
Climate of Bucharest, Romania
This portion of the Hermann’s tortoise range actually differs a bit from some of the other portions of the area. The winters here are colder than they are in other parts of the range, and the wettest month is actually June. Additionally, the humidity in Bucharest is higher than either Athens or Rome.
- July temperatures typically fall between 60- and 87-degrees Fahrenheit
- January temperatures typically fall between 23- and 37-degrees Fahrenheit
- July precipitation averages 2. 42 inches
- January precipitation averages 2.16 inches
- Humidity levels in July average 64%
- Humidity levels in January average 88%
Temperature Ranges
Given that I have now given examples of typical temperatures in the natural range of the Hermann’s tortoise, I will now shift to providing details of proper enclosure temperatures for those kept as pets.
Just understand that – as with almost every reptile maintained as a pet – you’ll want to establish a thermal gradient for your tortoise. This essentially means providing a range of temperatures inside the enclosure.
You can do this by clustering the heating devices (whether you use heat lamps, radiant heat panels, or some other heating device) at one end of the enclosure. This will create a “basking spot” directly under the heating devices, while the temperatures will gradually fall with increasing distance.
When setting the enclosure up this way, you’ll want the temperatures at the basking spot to be approximately 95 degrees Fahrenheit, while the temperatures at the opposite end of the enclosure should be in the mid-70s. It gets relatively cool in most portions of the Hermann’s tortoise’s range at night, so you can generally turn off the heating devices each night, unless the temperatures in your home drop below the mid-60s.
Note that the temperatures provided above are for adult Hermann’s tortoises; hatchlings and juveniles require slightly different conditions. Their basking spot should be slightly cooler (approximately 90 degrees Fahrenheit), while the cool end of their enclosure should be slightly warmer (the high 70s).
Additionally, young Hermann’s tortoise enclosures shouldn’t be allowed to cool off as much at night. Ideally, they should only cool to the low-70s each night.
Humidity Levels
While places that experience Mediterranean climates are often considered arid, they typically have relatively moderate humidity levels during the summer. Meanwhile, the winters have relatively high humidity levels. Accordingly, it’s important to avoid keeping your Hermann’s tortoise enclosure too dry.
Generally speaking, most keepers shoot for a relatively humidity level between about 40% and 60% for adult Hermann’s tortoises.
However, it’s always wise to provide your pet with options, much like you would with temperatures. You can’t easily set up a humidity gradient the way you can set up a thermal gradient, but you can set up different micro-habitats with varying humidity levels.
For example, it will generally be driest directly under the heating devices and in the surrounding area of the enclosure. On the other hand, the cool side of the enclosure will usually have a slightly higher humidity level. But you can also provide one or two damp hiding places to give your tortoise additional humidity options.
The best way to do this is by simply dampening the substrate under the hiding spot every few days. Alternatively, if your tortoise’s hiding spots have a “floor,” you can just add some damp mulch or soil to the hiding place.
Note that juvenile Hermann’s tortoises require much higher humidity levels than the adults, as they spend most of their time in burrows and areas with dense vegetation, where the relative humidity is higher. Accordingly, many keepers prefer to provide young individuals with humidity levels in the 70% to 80% range.
Tips, Tricks, & Considerations
Achieving the ideal temperature and humidity level for your Hermann’s tortoise is fundamental to their care, but isn’t always easy. So, I’ve listed a few helpful tips and tricks – as well as some things to keep in mind – below.
- If you’re having trouble getting the enclosure (or simply the basking spot) warm enough, you can try adding more thermal mass. Essentially, this means placing a dense object, such as a rock, brick, or cinder block, in the vicinity of the basking spot.
- There are several ways to increase the enclosure humidity, but the most common approaches include misting the substrate and enclosure walls with room temperature water, adding water directly to the substrate, and reducing the enclosure ventilation slightly.
- Bear in mind that live plants will increase the enclosure humidity. This may be advantageous in some cases, but it can be counterproductive in others.
- The greater the surface area of your pet’s water dish, the higher the humidity level will generally be.
- There is a difference between “humid” enclosure conditions and “wet” enclosure conditions. While it is sometimes important to provide humid conditions (such as when caring for young Hermann’s tortoises), you never want to keep your tortoise in wet conditions. Doing so can lead to bacterial and fungal buildup.
- It is especially important that your tortoise’s enclosure is not actually wet overnight, when the enclosure temperatures will fall. This can lead to respiratory infections and other health problems.
- Generally, the easiest way to reduce the enclosure humidity when necessary is by increasing the ventilation in the enclosure. Adding additional ventilation holes along the bottom of the enclosure walls is often helpful in these cases.
- While you must keep all pet reptile enclosures clean, this becomes increasingly important with higher humidity levels.
Citations
- Encyclopedia of Life Sciences – Mediterranean Ecosystems
- Time and Date – Athens, Climate
- Time and Date – Rome, Climate
- Time and Date – Bucharest, Climate
