how long to leave lights on

[sdiamond808]

How long do you leave the lights on? I have read 12 on 12 off, and in the summer change that to 13 on and 11 off, but somebody told me that since snakes are nocturnal to shorten the day light to 8 hours on and the rest off. I tried googling but couldn't find anything. Anybody have a good answer?

Thanks,

[craigafrechette]

I don't run a light cycle. I started out in this hobby almost 2 years ago and never have. Most species spend most of their time in hides or burrowed or hidden anyway. The natural sunlight through the windows is plenty of light for them

[ClockwerkBonnet]

Craig's advice is agreeable. Just don't let TOO much sunlight reach the cage, or the temps will rise to dangerous levels.

[sdiamond808]

I moved my cage because the sun was hitting it too much. Now it is completely shaded. So no natural sunlight. I still get in direct light in the room so its not pitch black or anything. So no day light leds or anything needed? and shortening to an 8 hour day is ok?

[craigafrechette]

Originally Posted by sdiamond808

I moved my cage because the sun was hitting it too much. Now it is completely shaded. So no natural sunlight. I still get in direct light in the room so its not pitch black or anything. So no day light leds or anything needed? and shortening to an 8 hour day is ok?

As long as your temps are right the lighting doesn't matter. My enclosures that have bulbs are on 24/7. I use the dark purple ones. The light is dim to the point that sometimes I can't even tell if they're on.
The natural sunlight that does get into the room is plenty

[Roman]

I disagree with Craig in this instance, we had this discussion before, so I don’t think it is necessary to start it all over again. I will just point out why I use light in all my enclosures and you can decide what makes more sense for you.

I use full spectrum lights, in smaller enclosures for juvenile snakes I use 35 W Halogen lights to create a local hotspot for basking and depending on the size of the enclosure a small LED light for ambient light. For the larger enclosures I use either a mixture between Metal Halide Lights for light, UVB and heat and LED lights or only Metal Halide Lights. The lights are on for 12 to 14 hours, depending on the season I will reduce this to 6 hours and during hibernation to no light.

The reason for this is that in my experience even nocturnal snakes (or other reptiles) will bask on occasion. They might not do this daily, but often enough to justify the light and the bright basking spot. Another reason is that reptiles can see part of the UVB spectrum, so if you don’t provide this light you deprive them of some colors they would usually see. I use only my lights for heating, so during daytime the temperature under some of my lights rise up to 35° or 40° C (95° to 104° F) as a hot spot, creating a thermal gradient to the opposite side of the enclosure with room temperature. The snakes use this hot spot to bask and warm up and will then move back into their hides or to cooler places, but they can use it whenever they wish. During nighttime I don’t use any heating, the temperature in smaller enclosures drops to room temperature, larger enclosures might hold some of the day temperature and stay a little warmer.

So in my opinion it is beneficial for snakes to provide them a “natural” day/night cycle and to provide full spectrum lights. As Craig and others already pointed out this is not strictly necessary for your snake to survive and many snakes will do good enough without lights and day/night cycle or just the (in)direct sunlight they get. I try to provide as much enrichment for my snakes as I can and light is one of the most integral parts for this.

[craigafrechette]

Yeah, Roman and I have disagreed on this in the past. Using lights certainly isn't wrong. I just don't see a need. In all my years keeping snakes I've never used a light cycle and have seen no ill effects. I've also never read anything that definitively says they need it. I just don't see a need to shine lights on nocturnal animals who thrive when secluded and hidden.

So, basically, if it ain't broke, why fix it?

But like I said, Roman isn't wrong either. But, until I see definitive research state that they need a light cycle I won't be switching anything up.
The vast majority of breeders I am aware of don't use light cycles either.

[Andy_G]

I use light cycles instead of brumation to cycle the colubrids I keep. I would say use the light if you want to, and perhaps do a bit of Google research to see the typical light cycle of where your boa comes from naturally, or replicate what is going on outside where you live. The beauty/confusion of this hobby is there are not always definitive answers.

[WolfMum13]

If there is no natural sunlight use a light. Snakes need UVB, also it is definitely beneficial to run a light cycle, whether diurnal, nocturnal. But that is only if you do not have any sunlight where the snake is kept.

[WolfMum13]

Sorry to answer your question fully. For your case yes use a light cycle, and replicate to a natural cycle. 12/12.

[ClockwerkBonnet]

Actually, snakes DON'T need UVB. It won't hurt them if you use it though.

[Andy_G]

Originally Posted by WolfMum13

Snakes need UVB

This is absolutely incorrect. The majority of species kept commonly in the pet trade do not, but it does benefit them if it can be offered.

[sdiamond808]

Thanks guys

[WolfMum13]

Actually that is a common and widespread fact that is incorrect. Current research shows that it aides in immune system, Vitamin D3 which aides in calcium,and as well as colorization for they’re vision. So yes do they NEED it like water, no, but it benefits the snakes. A lot of this stems from the idea that most species are nocturnal to they don’t see sun etc. Which also is in accurate because yes as stated above nocturnal animals do come out and bask during the day occasionally. Better to do research and look at your specific species rather than state a blanket idea over all species.

[Roman]

Originally Posted by ClockwerkBonnet

Actually, snakes DON'T need UVB. It won't hurt them if you use it though.

Originally Posted by Andy_G

This is absolutely incorrect. The majority of species kept commonly in the pet trade do not, but it does benefit them if it can be offered.

If you define “snakes don’t need UVB” as “they can survive without it for an extended period of time” you are right, but actually there are several studies telling a different story.

I participated at the “Bridging The Gap” joint event of the British Herpetological Society, the International Herpetological Society and the Advancing Herpetological Husbandry FB group a month ago. I was talking to Dr. Frances Bains and Roman Muryn (both did a long lecture about lights and their effect on our reptiles during this event) about lighting for enclosures and they told me they had found that D3-levels in blood samples of snakes kept without access to UVB where extremely low compared to snakes with access to UVB. They hinted that snakes who would only get Vitamin D3 through their (rodent) diet had just enough to live on, but the level was dangerously low compared to snakes with UVB light.

There are several papers to this subject

(1) Acierno, Mark J., et al. "Effects of ultraviolet radiation on plasma 25-hydroxyvitamin D3 concentrations in corn snakes (Elaphe guttata)." American journal of veterinary research 69.2 (2008): 294-297.

(2) Baines, Frances, et al. "How much UV-B does my reptile need? The UV-Tool, a guide to the selection of UV lighting for reptiles and amphibians in captivity." Journal of Zoo and Aquarium Research 4.1 (2016): 42.

(3) Jan H. Bos, et al. “Artificial Ultraviolet B Radiation Raises Plasma 25-HYDROXYVITAMIN D3 Concentrations In Burmese Pythons (Python bivittatus)”, Journal of Zoo and Wildlife Medicine 49(3): 810–812, 2018.

to quote just three of them.

Here is a quote from (3) about the process we are talking about:

“Vitamin D3 can be obtained from the diet or photosynthesized in the skin of most vertebrates[ ]. Photosynthesis of vitamin D3 occurs when the steroid 7-dehydrocholesterol present in the skin is converted to pre–vitamin D3 via exposure to UVb radiation (280–315 nm). The most effective wavelength for this conversion is approximately 297 nm. After this initial step, the precursor is thermally isomerized over several days to cholecalciferol, the actual vitamin D3. This vitamin binds to vitamin D binding protein, enters the bloodstream, and is hydrolyzed 25-hydroxycholecalciferol (25-OH-D3), which is considered the storage form of vitamin D and is therefore used as an indicator of vitamin D status. A second hydroxylation step takes place in the kidneys and yields the bioactive calcitriol 1,25-dihydroxycholecalciferol (1,25-OH-D3), which in turn regulates Ca and P absorption. This process is regulated by parathyroid hormone.

Both have their own significant roles: 25-OH-D3 acts as a hormone and regulates the cell division by directly or indirectly regulating cell cycling and proliferation, differentiation, and even apoptosis. 1,25-OH-D3’s main task is acting as a regulatory mechanism controlling the calcium level in blood serum. Captive reptiles often have imbalanced Ca : P ratios that are likely caused by vitamin D deficiencies, renal disease, or dietary imbalance. Whether reptiles require UVb exposure to attain a sufficient vitamin D status is currently unknown. A large variety of reptile species have increased vitamin D levels following UVb exposure, and certain species actively expose themselves to UVb radiation when they have a low dietary vitamin D3 intake.”

This study took blood samples of four Burmese pythons which had no access to UVB light previously and another blood sample after 310 days of being exposed to UVB light for 11 hours per day. The pythons could move away from the UVB light, they could choose to be under the light or avoid it. One sample was insufficient, but the three remaining samples showed a six fold increase of 25-OH-D3 concentration on average (from 39 to 244 nmol/L).

So even if our snakes get enough Vitamin D3 from their food this doesn’t affect their 25-OH-D3 and 1,25-OH-D3 blood level and that’s probably the main reason why those levels are as low as we find it in many cases.

Study (1) was about 12 adult corn snakes. All of them were kept identically, with one exception. 6 snakes were kept without supplemental lighting (group 1), 6 snakes were provided supplemental lighting (group 2). For the duration of the study the snakes were not fed for 4 weeks. As in study (3) they took a blood sample before and at the end of the study from each snake. After 28 days there was no significant increase in 25-hydroxyvitamin D3 concentration in group 1. In group 2 the plasma 25-hydroxyvitamin D3 concentration increased significantly (from 63.0 ± 36.96 nmol/L to 196 ± 16.73 nmol/L). With providing of UVB the concentration of 25-hydroxyvitamin D3 triplicated within 28 days.

Both studies showed that without providing UVB the concentration of 25-hydroxyvitamin D3 is much lower as it is in the same snakes if UVB is provided. Since it is also a hormone its function is limited if the concentration is low.

Both studies state that we don’t know yet whether this poses a significant health risk for our snakes or not. But since the snakes with access to UVB increased this concentration and snakes in the wild have even higher concentrations of 25-hydroxyvitamin D3 in their blood (Dr. Baines, personal message) it stands to reason that a higher concentration is desirable and has a positive effect for the snakes whereas low levels might not have an immediate effect for the health of our snakes, but might have long-term consequences.

There are other benefits as well. UV light is anti-bacterial and anti-fungal, so it helps reducing the bacterial and fungal load of the skin of our reptiles, even helping in better/faster healing of wounds.

Originally Posted by craigafrechette

So, basically, if it ain't broke, why fix it?

Craig – if we would talk about an IT issue (or any other machine) I would totally agree. If providing UVB would pose a risk for our snakes I would probably agree as well. But adding a UVB emitting fluorescent tube or metal halide lamp is neither a technical problem nor a big financial burden. The current generation of lights is safe to use if you install them accordingly (enough safety distance, heat protection etc.) and provides different levels of UVB depending on the reptile you keep. Even crepuscular or “nocturnal” animals will use them to bask during daytime, either basking with their whole body or by exposing only parts of their body.

If I know that my snakes might benefit form UVB and if it only takes (another) UVB emitting light to provide this benefit there is no question about “should I or shouldn’t I do it”. It has probably something to with our “reptile keeping philosophy”. In my experience many North American keepers have a “as-much-as-strictly-necessary” mentality (minimalistic enclosures, rack keeping), whereas many European keepers try to provide as much enrichment as possible (larger enclosures, full spectrum lights, natural look etc.). I certainly don’t want to generalize this, there are beautiful enriched enclosures in the US or Canada and minimalistic keepers here in Europe, but I think my assessment is valid anyway.

Sorry for the long rant (again), but I think this is an important issue and we can easily improve our husbandry without any major changes, just adding a light is sufficient.