Outdoor UVB

[jharrris]

I've been putting my tortoise outside in a zoomed tortoise house (like the picture) for a couple of hours 2 or 3 days a week. I provide water in a terra cotta saucer, a log and the enclosure has that shaded area. I do it when the UVB is at its highest point of the day. But she usually goes into the shaded part or burrows and I worry if she's getting the proper UVB she needs. I also feed her outside on warm days and try to do it during that same time where the UVB is high, an in sunspots. Is she getting the proper UVB? I know that there is UVB in shade but that area is completely covered up

 

[Alex and the Redfoot]

If it's not a complete darkness there, then there is an UV. Sun rays are probably magnitudes more intensive than indoor lights. So 15 minutes in a sunlight are worth of several hours of UVB lamp. With overall of 2-3 hours a week in the sun, UVB exposure should be enough.

But a change of the environment and really bright light can stress your tortoise so she naturally seek a safe place. You might try to place the box in the shade and open both lids. Something like a potted plant to hide under could provide both a safe place and enough sunlight. Also, if you do this routine less than a month, tortoise probably still haven't accustomed to it.

And I would still have indoors UVB lamp at hand for cold and rainy days.

 

[jharrris]

If it's not a complete darkness there, then there is an UV. Sun rays are probably magnitudes more intensive than indoor lights. So 15 minutes in a sunlight are worth of several hours of UVB lamp. With overall of 2-3 hours a week in the sun, UVB exposure should be enough.

But a change of the environment and really bright light can stress your tortoise so she naturally seek a safe place. You might try to place the box in the shade and open both lids. Something like a potted plant to hide under could provide both a safe place and enough sunlight. Also, if you do this routine less than a month, tortoise probably still haven't accustomed to it.

And I would still have indoors UVB lamp at hand for cold and rainy days.

Thank you! I've considered opening the top parts but I worry about safety. There are coyotes where we live and my neighbors have dogs that sometimes aren't leashed unfortunately

 

[wellington]

You could try covering just a portion of the screen area and see if he would stay out of the heavier shaded area. Also if it's too cold for him, that might be why he is going in the hide area. You could add a incandescent flood heat bulb for added heat.

 

[jharrris]

You could try covering just a portion of the screen area and see if he would stay out of the heavier shaded area. Also if it's too cold for him, that might be why he is going in the hide area. You could add a incandescent flood heat bulb for added heat.

I do it when the weather is warm but I do use that kind of bulb indoors and maybe I could use it outside too. Thank you!

 

[SuzanneZ]

Thank you! I've considered opening the top parts but I worry about safety. There are coyotes where we live and my neighbors have dogs that sometimes aren't leashed unfortunately

An old saying is "Err on the side of caution." In the case of coyotes and loose dogs extreme caution isn't overthinking.

 

[Alex and the Redfoot]

Unfortunately, half closed box won't help with dogs and coyotes. If this is really an issue - then it's better to keep the lid closed. And wellington's suggestion about the incadescent bulb will work better. I think there might be waterproof fixtures and extension cords for them in a car parts or hardware store.

 

[SuzanneZ]

You could make a cover out of a sturdy wire; hardware cloth or rabbit wire.

 

[jaizei]

Sun rays are probably magnitudes more intensive than indoor lights. So 15 minutes in a sunlight are worth of several hours of UVB lamp. With overall of 2-3 hours a week in the sun, UVB exposure should be enough.

that uvb lights are inherently weaker than sunlight is a dangerous way to think. some lights can produce much more intense uvb than what would be experienced naturally in sunlight.

 

[Alex and the Redfoot]

that uvb lights are inherently weaker than sunlight is a dangerous way to think. some lights can produce much more intense uvb than what would be experienced naturally in sunlight.

Yes, that's true, thanks for pointing that.

Please, correct me if I'm wrong - I'm not trying to argue, just want to check if I understand things right.

UVB lamps have UVI up to 8.0 (distance less 30 cm), while sunlight in some regions during summer season might peak at UVI 12-14. And if we compare UV output of a 15% UVB lamp with UV provided by a winter sun in UK, then yes, lamp's UV levels would be far more intense. Yet, when comparing the same lamp with a sunlight in July in Egypt or UAE, lamp's UV output would be much lower.

For tortoises most popular lamp is 12%, mounted at 18-20" which translates to UVI 4. This is half of summer daytime UV and double to winter daytime UV (in UK) and it's not extremely intensive.

 

[Tom]

Yes, that's true, thanks for pointing that.

Please, correct me if I'm wrong - I'm not trying to argue, just want to check if I understand things right.

UVB lamps have UVI up to 8.0 (distance less 30 cm), while sunlight in some regions during summer season might peak at UVI 12-14. And if we compare UV output of a 15% UVB lamp with UV provided by a winter sun in UK, then yes, lamp's UV levels would be far more intense. Yet, when comparing the same lamp with a sunlight in July in Egypt or UAE, lamp's UV output would be much lower.

For tortoises most popular lamp is 12%, mounted at 18-20" which translates to UVI 4. This is half of summer daytime UV and double to winter daytime UV (in UK) and it's not extremely intensive.

That is all correct IF someone is using them correctly.

Remember that some people mount them too low, don't use a meter to check the levels, and also run them all day, which is far longer than the UVB peak that happens outside.

Also, while UVI level of 12-14 may occur at some point somewhere in the world, the highest I ever get here in SoCal would be around 8 at mid day when UV is at its peak. There is no where in the world that has UVI over 8 all day long. That would be peak at its highest level.

 

[Tom]

I've been putting my tortoise outside in a zoomed tortoise house (like the picture) for a couple of hours 2 or 3 days a week. I provide water in a terra cotta saucer, a log and the enclosure has that shaded area. I do it when the UVB is at its highest point of the day. But she usually goes into the shaded part or burrows and I worry if she's getting the proper UVB she needs. I also feed her outside on warm days and try to do it during that same time where the UVB is high, an in sunspots. Is she getting the proper UVB? I know that there is UVB in shade but that area is completely covered up

Those houses are not good for this purpose, or any other purpose for that matter. The walls are too tall for the amount of surface area at the bottom. You need something wider with shorter walls. Also, almost all tortoises avoid the mid day sun when UV is at its highest levels. They may bask at noon in cooler weather, but most will stay hidden mid day in hotter weather.

Still, your tortoise is likely getting all the UV it needs.

Examples:

 

[jaizei]

Yes, that's true, thanks for pointing that.

Please, correct me if I'm wrong - I'm not trying to argue, just want to check if I understand things right.

UVB lamps have UVI up to 8.0 (distance less 30 cm), while sunlight in some regions during summer season might peak at UVI 12-14. And if we compare UV output of a 15% UVB lamp with UV provided by a winter sun in UK, then yes, lamp's UV levels would be far more intense. Yet, when comparing the same lamp with a sunlight in July in Egypt or UAE, lamp's UV output would be much lower.

For tortoises most popular lamp is 12%, mounted at 18-20" which translates to UVI 4. This is half of summer daytime UV and double to winter daytime UV (in UK) and it's not extremely intensive.

though they have fallen out of favor, a new MVB can have UVI of 30+ @ 30cm.

Arcadia T5 14% is 10+ @ 30cm

cheap bulbs from unknown manufacturers (eg many of those found on Amazon) can have UVB (and UVC) from the portion of the spectrum that never reaches the ground. This is the reason why a 6.5 alone can not ensure that UVB bulbs are 'safe'

 

[jharrris]

Thank you guys!

 

[SuzanneZ]

Those houses are not good for this purpose, or any other purpose for that matter. The walls are too tall for the amount of surface area at the bottom. You need something wider with shorter walls. Also, almost all tortoises avoid the mid day sun when UV is at its highest levels. They may bask at noon in cooler weather, but most will stay hidden mid day in hotter weather.

Still, your tortoise is likely getting all the UV it needs.

Examples:
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Cool ideas. Thank you.