Reptile & Amphibian Forums

So, for dragons, most people seem to give them a basking spot in the 100-110 degree range. When this temp is measured, is it the temperature of the surface of the basking platform that is being measured, or should this be the air temperature above the basking spot? I would assume that the basking area material would then get hotter than 100-110 degrees. I wonder the same thing about UTH's. DOes the ambient ait temp of 85-90 mean that the actual surface needs to get hot enough to raise the air temps, or does just the surface need to be at 85-90 and the air above can stay at 77-82?

ambient temperatures is just that, air temperature. Surface temperatures is the temperature on the surface of an object, not the air above it.

For dragons basking temperature is the surface temp of the basking spot. Warm end of the cage ambient temps should be 80-90F with cool end ambient temps dropping to 70-80F with nighttime temps being 65-70F.

Only two accurate ways to measure surface temp and that is with a temp gun (best) or thermometer with probe, with probe directly on top of the surface. Air temps can be with quality stick on dial type thermometers or the probe suspected midair.

For undertank heaters (which I don't recommend as a heat source for dragons at all) surface temp is the surface right above the heater (basically as close as the dragon could get to the area the UTH is. If underneath a glass tank then it will be the temp on the glass inside the tank. UTH should never be placed inside a cage. UTH should also always be controlled by a proportional thermostat to ensure they don't' get too hot. As most lizards are very poor judges of temperature from their bellies (unlike snakes that are better capable), burning their underside or damaging internal organs is very easy through belly heat.
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PHLdyPayne

Thank you for the reply, and it cleared a lot of things up. I also found some information regarding this topic on the pro-exotics website FAQ's. The UTH will be on a rheostat, and will be closely monitored to assure that it is not hot enough to burn the dragon, it is mostly an extra option to give the dragon some warmth over a slightly greater area. In addition, I live in a pretty cold state and it is just one more thing to fall back on if a light bulb goes out that evening. Of course once the pellet stove is up and running for the season we'll all be nice and toasty anyway.

UTH are a waste. Desert reptiles are designed for heat from above. Nowhere on nature does heat come from below. UTH heat substate, bulbs heat air and provide needed light to encourage activity and proper eating habits. If the bulb burns out your dragon will be fine for a day till you replace it. In the whild there are cold and cloudy days.

Actually, for hours after sunset, heat does come from below, radiated from the soil, the rocks, different thermal masses.

In civilization, reptiles search out belly heat from the asphalt roads after dark, resulting in car squashed reptile pancakes.

Belly heat can be beneficial as a supplemental heat, Under Tank Heaters can also work to bump up slightly low ambient temps. Not good as a primary heat source, but when used correctly, they do have use possibilities.
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robyn@proexotics.com

Pro Exotics Reptiles

Excellent post Robyn

Scott Clark
www.CherryDragons.com

I agree, belly heat is beneficial for beardeds. That's why I prefer to use flat rocks/bricks for my beardeds to bask on...they absorb more heat than wood, and make a nice balanced hot spot for the beardeds. Josh

Many reptiles do use belly heat, sun warmed rocks, asphalt, sand etc. but nearly all of these are nocturnal reptiles or reptiles more active during dusk/dawn than fully diurnal reptiles. Any surface in the sun will be warmed up but basking lights will do that just as fine.

It is when under tank heating is use primarily as a heat source for day active reptiles they can pose a serious risk. This is why hot rocks are notorious in causing severe burns to reptiles. Undertank heaters are fine for day active reptiles to provide some warmth when the ambient temps drop lower than normal (for bearded dragons 65F or less at night.) Keeping the cage too warm with these things at night will just stress the dragon more.
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PHLdyPayne