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How Do You Know If a Lizard Is Too Cold?

If you are preparing for a new lizard, or just curious about them, you may wonder how you can be sure if it’s the right temperature…

How do you know if a lizard is too cold?

When lizards get cold, they slow down, and this behavior is called diapause. By reducing bodily function, a reptile can reduce their overall energy consumption so that they can use their body fat as fuel to warm themselves.

Functions that are affected include things like digestion and movement, so a cold lizard will become very lethargic and almost unresponsive – in some cases, even if you pick them up.

If you see this, then it’s best to check the temperature range of the cage with a handheld electronic thermometer or if this is not available, you might be able to use pet store sticker thermometers placed on the bottom of the glass and spaced across the cage.

This will allow you to get a good idea of the range of temperatures inside, but the electronic model is much more accurate and well worth the investment for ensuring your pet’s health and comfort.

What could cause a lizard’s enclosure to get too cold?

A white snowman outdoors on the snow.

A white snowman outdoors on the snow.

Some of the most common causes of temperature fluctuation in a lizard’s enclosure are easy to overlook if you are not careful. First, you want to consider the cage placement. If it is close to an A.C. vent, for instance, then it will be colder at certain times, especially at night when the heating lamp is off.

Speaking of nighttime, if your lizard’s cage is typically warmed during the day by a window placement that allows them to get sunlight in their cage, then you want to measure its temperature at night. The window is less insulated than a wall placement and the temperature might well become much colder when it’s dark and the A.C. is still running.

Finally, the mesh top of the enclosure on many cages is going to be susceptible to air circulation and the resultant cooling from this, so you’ll want to be sure to turn off the ceiling fan at night if you haven’t checked the nighttime temperature of the enclosure.

You can turn it back on once you know for sure that it’s warm, but until then it’s always best to err on the side of safety.

What could happen to a lizard if it gets too cold?

When a lizard gets cold, various important functions begin shutting down, and this can be quite dangerous for their health. Movement is the first thing that you will notice. Your lizard will seem less responsive and much more lethargic, likely just sitting still for longer periods than usual.

Sometimes with the cold, they can’t move at all – so it’s important to notice when they are suddenly less lively if they are newly arrived and you are uncertain if their environment is warm enough. Aside from movement, digestion is also affected, and your lizard will lose their appetite and cannot properly digest what they DO eat.

This causes their food to begin rotting inside of their bellies, which is quite dangerous and potentially lethal! Finally, during the time that they are cold, they also will defecate very little or even not at all and may fall into a slumber that they cannot wake up from until they have properly warmed up again.

If you see these signs, it’s best to get your lizard into the vet for a checkup right away. Cold, especially in cases of repeated or prolonged exposure, can be very dangerous to your lizard’s health!

What is too cold for a lizard?

A person holding ice outdoors during the day.

A person holding ice outdoors during the day.

It’s going to depend on the species of lizard that you have, but in general, an enclosure should have an inside temperature range falling between 70 to 85 degrees, with a basking spot that can be between 88 to 100+ degrees, depending on that lizard’s needs.

When it’s colder than this, your lizard will start showing signs of diapause, and at under 45 degrees temperature then they can lose the ability to move at all and the cold is potentially lethal to them.

Do all lizards need a heated enclosure?

A heated enclosure is generally going to be best. Heat and light are very important for reptiles and climate control helps to ensure that you are providing them with an environment that simulates what they are used to.

Without heated areas, for instance, you can get a lot of temperature variance at night, which in turn can slow their metabolism and even initiate diapause during the time that they are too cold.

A heat lamp, by contrast, helps to regulate temperature but can also ensure that they get UV rays, which help them to produce vitamin D3 to properly digest calcium. While there are certain scenarios where a lizard might be alright without a heated enclosure, it is best to get one to ensure their comfort and health.

How do you heat a lizard enclosure?

You have a lot of options when it comes to heating your lizard’s enclosure, with the most common being a simple heating pad. This can help to ensure that one area of the cage is always warm and comfortable for your lizard and they will usually spend most of their time there.

A UV heat lamp is also a good idea, as this will help to ensure that your lizard can bask in the light and let the UV rays encourage the production of Vitamin D3 in their bodies. This will help them to digest the calcium properly and to stay in good health.

Finally, pet stores also offer several heated objects, with heated rocks being a popular option that your lizard is sure to love.

While sunlight can certainly warm the cage during the day, you will want to invest in one or more of these heating options to make sure that your lizard is as comfortable as possible and thus happier and healthier.

Why are lizards known to be cold-blooded?

When you hear the term ‘cold-blooded’, this refers to your lizard’s inability to regulate its heat. Unlike birds and mammals, reptiles don’t adjust their internal temperatures ‘on the fly’ but are reliant instead on their surrounding environment.

Simply put, their blood temperature changes based on where they live and what’s around, so climate control is essential if your lizard is to survive and live a happy, healthy life.

How long can a Bearded Dragon survive without heat?

If the internal temperature of the enclosure (measure the floor for best results) is at least 65 degrees, then your Bearded Dragon may last up to 24 hours before they begin to enter a state of diapause.

That said, you can certainly still turn off the heat lamp at night, as this simulates night and day and unless it gets very cold at night, your Beardy should be just fine. Just be sure to take measurements of the night temperature of the enclosure for best results before you set a schedule for turning off the heat.

While your Bearded Dragon looks tough, they are quite sensitive to temperature changes and can quickly become ill if diapause initiates too frequently or for too long, so temperature regulation is going to be vital to their prolonged health.

What happens if a Leopard Gecko gets too cold?

When Leopard Geckos get too cold, things can go downhill very quickly. Their digestive systems, for instance, will not properly process their food, which instead begins rotting in their bellies and can poison their systems.

They can also become impacted during this time, unable to eliminate waste, which is also very dangerous for your Gecko.

Provided that you have heat pads and other heating methods in the enclosure and they are tested periodically, then this should be easily avoidable, but if you have a power outage or the heating pad has ceased to function and your lizard seems lethargic, then a vet checkup is a good idea to make sure that your Leopard is okay.

What do lizards do when it’s cold outside?

When it’s cold and a lizard is living outside, they will find the warmest place that they can and begin a process called diapause. Diapause is a survival mechanism that works by shutting down several bodily functions so that the lizard requires very little energy and can stay alive by utilizing only its body fat.

During this time, they will move very little or not at all, and likely they will not eat, as movement and digestion are part of the functions impacted by this natural survival strategy. Rather, their metabolisms slow down and the lizard will fall into a torpor, essentially sleeping their time away until it’s warm outside again.


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