Lighting
UVB
Recent studies suggest that UVB is beneficial for snakes’ long-term physical and mental health. Like many snakes, Dumeril’s boas are a Ferguson Zone 2 reptile, which means that they need a UVI of 2.0-3.0 in the basking area (closest location to the UVB lamp). UVB intensity decreases with distance from the source, so your snake’s basking surface needs to be placed at an appropriate distance. If it’s too close, your snake may get “sunburned.” If it’s too far away, your snake may not be able to actually benefit from having the lamp.
ReptiFiles strongly recommends that reptile owners invest in or at least borrow a Solarmeter 6.5 to measure UVI (UV Index) for proper basking surface placement. However, if you don’t have access to a Solarmeter 6.5, here is an estimate of how far away your snake should be when basking under the UVB lamp, since UVB intensity is affected by distance.
Lamp mounted above mesh (recommended for safety):
- Zoo Med T5 HO Reptisun 5.0 / Arcadia 6% — 10-14″ / 25-35cm
- Zoo Med T5 HO Reptisun 10.0 / Arcadia 12% — 16-20″ / 40-50cm
Without mesh obstruction:
- Zoo Med T5 HO Reptisun 5.0 / Arcadia 6% — 14-18″ / 35-45cm
- Zoo Med T5 HO Reptisun 10.0 / Arcadia 12% — 21-25″ / 52-63cm
The above distance recommendations assume a ~35% mesh block. For more details on estimating basking distance based on mesh obstruction, see the Facebook group Reptile Lighting > Guides > Guide 1: Using T5-HO lamps above a Mesh Screen.
Your UVB bulb should be roughly half the length of your enclosure (ex: 34″ if the enclosure is 6′ long). It will also need to be installed in a Vivarium Electronics T5 HO or Arcadia ProT5 fixture. Optimal use distance is likely to be more variable if you use something different.
Make sure your UVB fixture doesn’t have a piece of glass or plastic to “protect” the bulb. UVB rays are blocked by glass and plastic, rendering that bulb you just spent so much money on completely useless. Naked UVB bulbs are effective UVB bulbs!
Day Length
Place your light on a timer
to help your snake regulate its day/night and seasonal cycles:
- Spring — 12 hour day
- Summer — 13 hour day
- Fall — 12 hour day
- Winter — 11 hour day
Alternatively, you can sync your boa’s lights to your local sunrise/sunset times for similar results. I prefer using the Kasa Smart Power Strip to manage my reptiles’ light schedules from my phone.
Temperatures & Heating
Like all reptiles, Dumeril’s boas need a heat gradient so they can regulate their own temperature. This temperature gradient is more effectively accomplished in large enclosures than in small terrariums or tubs.
- Basking area (ambient): 86-88°F (30-31°C)
- Cool zone: 70-75°F (21-24°C)
Night temperatures can safely drop down to 68-75°F (21-24°C), and is actually better for the snake’s long-term health if provided. This is typically easily accomplished by turning off the heat source at night. If the snake’s enclosure is located in a particularly cool room, then it’s recommended to use a gentle source of nighttime heat such as a ceramic heat emitter or radiant heat panel, discussed later.
Measure the temperatures that your snake is feeling with a digital probe thermometer like the Zoo Med Digital Thermometer and Humidity Gauge, with the probe placed on the basking surface.
Do not use a stick-on thermometer, as these will not give you accurate results.
How to heat your Dumeril’s boa enclosure
In nature, warmth comes from the sun (above), not from the ground (below). In fact, reptiles retreat underground to escape the sun and get cooler, not warmer. Providing warmth from below, as with a heat mat, is therefore unnatural and will promote unnatural behaviors. Heat lamps solve this problem by mimicking the effects of the sun and warming both the air and the ground below.
Of course, there are several different types of heat lamps:
- Halogen and “incandescent” heat bulbs produce primarily IR-A and IR-B.
- Deep heat projectors and other carbon-filament bulbs produce primarily IR-B and IR-C.
- Ceramic heat emitters produce primarily IR-C.
Considering that the goal is to replicate sunlight as the primary source of heat in a Dumeril’s boa’s environment, I recommend using incandescent and halogen heat bulbs as the most effective method of providing heat to your Dumeril’s boa.
The absolute BEST heat lamp on the market is the Reptile Systems Gold Infrared Lamp Unit. The particular construction of this unique incandescent lamp produces extremely high levels of IR-A, making it extra effective for heating poikilotherms (i.e. reptiles). It also has a very long lifespan, which helps justify the investment.
If the Gold Infrared lamp is more expensive than what you have budget for, the next best choice is a standard heat lamp. Both reptile-branded and generic incandescent bulbs can work well for the purpose, but not all incandescent bulbs are appropriate for heating reptiles. Here are my preferred bulbs:
Halogen bulbs are generally best when used over mesh, and the spot bulbs are generally best if you have to install your heat lamps inside the enclosure.
How many watts? The exact wattage you will need depends on the height of your enclosure and your room temperature. If it’s a little too hot, use the dimmer switch on the heat lamp to dial it down to the right level.
How many heat lamps? ReptiFiles recommends using a cluster of multiple heat bulbs in order to create a larger basking area, which will heat your snake’s body more evenly and encourage more efficient thermoregulation and healthier circulation.
- PRO TIP: Beware “environmentally-friendly” light bulbs. These bulbs advertise a high wattage, but actually use fewer watts while maintaining the same light output as the advertised wattage. This is great for household lighting, but in a reptile enclosure you need the warmth that extra energy expenditure provides. If you can’t find a good bulb, a reptile day bulb from a pet store works, too, although it will likely have a shorter lifespan.
If you are concerned about “belly heat,” placing a light-colored flagstone or concrete pavers under the heat lamp will absorb warmth that your snake can curl up on. In fact, I recommend doing this anyway.
Ceramic Heat Emitters (CHE) and Radiant Heat Panels (RHP)
I don’t recommend these for daytime heat, but if you need a lightless heat source for nighttime or need help with boosting the general air temps inside your enclosure, a ceramic heat emitter is a good choice. Ceramic heat emitters produce ambient heat, also known as Infrared-C. It’s the weakest form of infrared, but it’s also the form of heat that Dumeril’s boas are most likely to encounter at night. For larger enclosures, it’s best to use a radiant heat panel instead of multiple ceramic heat emitters.
Either way, you will need to hook up each heat source to a thermostat in order to maintain safe nighttime temperatures for your Dumeril’s boa. CHEs can be used with a non-proportional (on/off) thermostat like Inkbird, but RHPs should be used with a proportional (dimming) thermostat like Herpstat.
What about heat mats?
Under-enclosure heating devices like heat mats and heat tape are popular for use with snakes, especially terrestrial species. And they can be used, as long as they’re controlled by a thermostat. They can be particularly effective for creating a warm hiding area. However, they struggle to warm the air inside an enclosure, and produce relatively weak infrared.
In other words, it’s best to stick with heat lamps for your primary heat source.
CAUTION: Do not use heat rocks!
For some inane reason, heat rocks are still being sold by pet stores as a “safe” source of heat for your reptile. Though safety improvements have been made in recent years, there is still a danger of your snake getting burned. Furthermore, they’re not a good choice for heating your enclosure, as the device only warms the rock, not the surrounding air.
CAUTION: Use a lamp guard/bulb cage!
If you plan to install the heat source inside your snake’s enclosure, make sure it is surrounded by a lamp guard/cage to prevent your snake from getting burned by direct contact. (Amazon) (Arcadia)
Humidity
Dumeril’s boas are native to the spiny thickets/forests of southwestern Madagascar, which are part of the xeric shrubland biome. Xeric shrublands are a type of desert that receive less than 250mm of annual rainfall. Because it receives so little rain, this part of Madagascar is considered quite dry. However, it’s not the Sahara desert and the habitat shouldn’t be treated as such.
According to experienced keepers, Dumeril’s boas do best with an average humidity between 40-60%. If you live in a moderate to high humidity area, this shouldn’t be hard to achieve. Occasional misting at night (with a pressure sprayer like this one) can be used to create humidity spikes, especially when the snake is about to shed. If you find that you’re still struggling with humidity levels, mix water into the substrate as needed for a more consistent increase in humidity.
- PRO TIP: Use distilled water for misting (not drinking). Hard water stains are tough to get rid of, but using distilled also extends the life of your mister.
Keep reading about Dumeril’s boa care:
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