Box turtles can’t regulate their own body temperature without help.
In nature they rely on the sun for heat and shade or water to cool down.
When you keep one as a pet, you need to make sure she has access to both warm and cool areas so she can still move around her environment to warm up or cool off.
Why Can’t Box Turtles Control Their Own Body Temperature?
Well, technically they can, they just have to use their environment to do it. Humans are endotherms, meaning their bodies can generate heat as needed to keep their body at a constant temperature. Box turtles are ectotherms, which can’t generate heat. Their body temperatures vary depending on the temperature of the air around them.
This means they get very sluggish in cold weather. And they can overheat on a hot, sunny day if they can’t find shade or somewhere to burrow.
How Does the Right Temperature Help Your Turtle?
Turtles need warm temperatures to eat. When temperatures are too cold, their metabolism slows down, as if they are preparing for hibernation. They move around less and eat less. Warm, moist conditions stimulate them to eat. They also like to bask (sit in a warm spot) after eating.
And if they have an infection, they will also look for an area with high heat. This is similar to humans getting a fever from an infection. It raises the body temperature to try to kill the invading germs.
So What Daytime Temperature Does a Box Turtle Need?
In general, you want a temperature gradient that ranges from around 75 °F – 80 °F (24 °C to 27 °C) on the warm side and about 70 °F ( 21 °C) on the cool side.
She will also enjoy a basking area that gets to about 85 °F (29 °C). This is not as critical as the gradient, but if you have room to provide it, try to do so. But most of the pen should be on the cooler side, so if trying to provide a basking area heats up the whole cage too much, then just go with the gradient.
The water source should be on the cool side. If you don’t have bedding in the whole habitat, at least keep moist bedding (deep enough to burrow into) on the cool side, too.
Can Nighttime Temperatures Be Cooler?
Yes, just like in nature, over-night temps can be cooler. Down to about 60 °F (15 °C) is acceptable. If you keep your home at least that warm, then you can simply turn off heat lamps at night.
How Do You Create a Temperature Gradient?
The simplest way is to set up a heat lamp at one end of the habitat. Depending on the size of your set-up, this might be all you need. Regular incandescent bulbs also give off heat. In a smaller cage, these could also provide enough heat.
No matter what bulb you use, when first setting up your heat source, you will need to check the temperatures directly below it and at the other end. They should fall within the above ranges. Remember to measure the temperatures at the same level as the turtles. Measuring closer to the lamp will give you an artificially high temperature.
You might need to adjust the height of the lamp up or down to get the temperature right. Just make sure the lamp doesn’t get too close to any wood or plastic.
Some people recommend under-tank heating pads, but this is not really natural. Turtles are used to overhead heat, and you want to mimic nature as much as possible to keep your pet happiest.
Setting a rock directly under a basking lamp is a good way to create the higher-temperature basking area. Be careful, though. You don’t want it to get too hot and burn your pet. That’s also why the electric heated rocks you can buy are also not a very good idea. You can’t really control the temperature on them.
Creating Hot and Cool Areas Outside
If you keep your box turtles outside year-round (or even just during the warmer months), you’ll generally have an easier time with the temperature control. Just make sure one side of the enclosure gets plenty of sun for most of the day. And keep the other side shaded. You can either cover one end or plant shrubs next to or in the pen (depending on how big it is). Just be sure your turtles can’t use the plants to climb out! Even if you do cover one side, that side should still be in a relatively shady area or the sun can still overheat it.
And that’s it. It can take a little time and effort to get it all set up and the temperatures in the right ranges. But once you’ve done that, you just need to check the temperatures once in a while to make sure they’re still where they need to be.