While there are some exceptions, the majority of reptiles (and amphibians) need both UVA and UVB light in order to stay healthy.
The reptile lighting industry is massive with dozens of options for every herp keeper and every type of reptile.
What about black lights? If you’ve ever seen a snake under a black light then you know just how cool it can be to check out your reptiles under the black light.
But are black lights safe for reptiles?
Black lights that are used for parties or to make posters glow contain only UVA light which makes them a poor choice for reptiles that also need UVB light. Additionally, these black lights can cause eye damage in some reptiles. Specialty pet stores can offer reptile-safe black lights that produce both UVA and UVB light.
I know, that’s a bit confusing and in most cases, it’s easier to just avoid black lights altogether. But if you’d like to learn more, we’re going to take a closer look at everything you need to know about black lights and reptiles.
3 Reasons Why Most Black Lights Are Bad For Reptiles
We know that black lights aren’t a good choice for herps but let’s take a closer look at why.
1. Most Black Lights Don’t Produce UVB Rays…And That’s Bad For Reptiles
Black lights like the ones that you’d find in a party supply store emit only UVA rays and zero UVB rays.
While this can be fun when it comes to making your sneaker glow, it doesn’t work for reptiles that need UVB rays in order to stay healthy. Without a steady source of UVB rays, most reptiles (and especially bearded dragons) will be unable to produce enough vitamin D.
Low vitamin D eventually leads to low calcium and finally results in metabolic bone disease. This condition is completely avoidable with proper diet and appropriate lighting which includes both UVA and UVB rays.
But because your standard party store black light only emits UVA, its exclusive use will eventually lead to this dangerous condition.
2. Prolonged Black Light Exposure Can Damage Eyes
There’s plenty of evidence that prolonged and direct exposure to heavy amounts of UVA rays can damage human eyes and it seems likely that our reptiles are at risk as well.
Of course, herps should have a place to hide regardless of their light source but we don’t want to make things worse by exposing them to powerful UVA rays exclusively.
3. Black Lights Can Interrupt Your Reptile’s Natural Routine
Just like humans, reptiles have a circadian rhythm that depends on the night and day cycle. In their natural environment, UV lights would be produced during the day (by the sun) and little to no UV light would be present at night.
In most cases, black lights are used for evening or low light viewing of your reptiles. That means your reptile’s usual cycle will be completely flipped on its head as they’ll be exposed to UVA light outside of their normal hours.
This can throw off a variety of natural cycles and rhythms for your reptile.
Incandescent Bulbs Are Better Than Black Lights For Evening Reptile Viewing
A desire to view their reptiles in the evening without turning on their full lighting set up is usually what drives people to use black lights in the first place but incandescent light bulbs are a far better choice.
Incandescent bulbs don’t emit any (noticeable) UV light which means you can use them without interrupting your reptile’s normal cycles.
You’ll commonly see these labeled as red or black “heat” bulbs but you’ll always want to check the description and confirm that they’re incandescent heat bulbs.
While I prefer the red-colored options, they do make these in black as well. However, a black incandescent light bulb is very different from the UVA-producing black light that you’d find at a party supply store and these won’t make anything glow as a party light would.
Incandescent bulbs may not make your snake glow but they will let you view your reptile without ruining their night or causing any damage.
There Are Reptile-Friendly Black Lights…Sort Of
If you really dig deep you can find black lights that can emit both UVA and UVB rays which can make them acceptable for reptiles.
Again, you aren’t going to find these at the party supply store!
Black lights from the party store fall into a bigger category of lighting that includes all kinds of ultraviolet bulbs. Distinctions between the bulbs are made based on wavelength which is measured in nanometers (nm).
UVB rays are in the 280 to 315nm range and you can find black lights that emit rays in this range. But they’re not easy to find since they don’t have as many uses outside of reptiles.
These lights break down even further into BL and BLB distinctions with plenty more distinctions between nanometers.
But rather than becoming an expert in ultraviolet light, it’s better to stick with a reptile-specific light setup that keeps your herp happy and healthy. Then turn to incandescent bulbs when you want to view your reptile in lower light.
A Little Black Light Can Be Okay…And Even Helpful For Snake Breeding
So we know that black lights aren’t good for our herps, so what’s with all these YouTube videos of people shining the light on their snakes to bring out these crazy colors?
Well, in most cases, a little black light isn’t a problem. The issue is with long-term use or when it’s used to replace more traditional lighting set up.
Long-term black light usage isn’t good for anyone, including you.
But most herps won’t be harmed with a little black light to bring out their hidden patterns In fact, a black light can actually help keepers identify certain traits that they may want to breed and this video does a great explaining how this can work:
However, it’s up to you to keep black light usage to a minimum or decide whether you want to use it at all.
If you do decide to use a black light for a different view of your reptiles, make sure to use something in the 365nm range. Anything outside of that range won’t have the effect you’re looking for.
Frequently Asked Questions About Reptiles and Black Lights
Black lights can be confusing so let’s dive into some additional questions you may have around herps and black lights.
Do Black Lights Bother Snakes?
Yes, black lights like the ones you’d find at a party store can bother snakes. While it can vary by species, most snakes are sensitive to UV light and traditional black lights produce heavy amounts of UVA rays that snakes are sure to notice.
Can A Black Light Hurt A Bearded Dragon?
Black lights that are used to light up posters or sneakers emit large amounts of UVA rays that are not only harmful to your bearded dragon’s eyes but they can also be harmful to you. Additionally, black lights don’t emit UVB rays which are critical to the health of your bearded dragon.
Are Black Lights Bad For Geckos?
Not only can the powerful UVA rays from most black lights harm a gecko’s sensitive eyes, but the UV rays can also interrupt the gecko’s usual nocturnal cycle. It’s not natural for UV light to be present at night and its presence can greatly disrupt their natural rhythms.
Can Ball Pythons See Black Light?
Studies suggest that as a species that hunts at night, ball pythons are able to see UV light and black lights primarily produce UVA light. While we can’t know for certain what ball pythons see, it certainly appears that they can see black light.
Is Black Light Good Or Bad For Leopard Geckos?
A traditional black light similar to what you’d find at a party store is not good for leopard geckos. These lights emit a large amount of UVA light which can interrupt a leopard gecko’s normal sleep cycle and even harm the eyes. Incandescent black bulbs, however, can be used for evening viewing.
Do Rattlesnakes Glow Under Black Light?
Most snakes, including rattlesnakes, glow under a black light. However, rattlesnakes don’t glow as much as other snakes so it shouldn’t be used as a way to find them in low light. Especially since there will be many other objects that will glue under the black light.
As is often the case in the world of herpetoculture, things aren’t always so straightforward and black lights are one of several things that aren’t good for reptiles.
But what really makes things confusing is how the word “black light” is used interchanging between lights that have massive differences in wavelength and the type of UV emitted.
That’s why it’s usually better to stay on the traditional path when it comes to something as important as reptile lighting and stick with products that are made specifically for herps.
When it comes to night or evening viewing, red or black incandescent bulbs are definitely the way to go!
What do you think? Are you going to start viewing your herp under the red light?