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I just finished a 4'Wx2'Dx4'H cage for my juvenile iguana, Rex. He seems to have taken to it well.

Lighting, however, has been a bit tricky. The cage (pictured in part below) is open; we keep our house at about 76F. Thus I constructed a basking shelf, with lighting, high on one end of the cage.

The cage has a 24-inch 5% UVB light and a 100W heat bulb, both about 10 inches above the basking shelf.

In the photo, the heat bulb is off, both to make photography possible and because Rex reacts strangely when it is on.

When I turn on the heat lamp, Rex climbs up and hangs *directly* beneath the lamp -- less than an inch away from the hot bulb! We could see the light shining THROUGH HIS EARS (which glowed red!)

I was a tad surprised, and have kept the lamp off. Once the light is out, Rex settles back onto the shelf, and looks quite comfy. He's eating and pooping well, so I'm trying to figure out what to do about his moth-like obsession with bright lights.

Perhaps I need to use a ceramic heat source?

The last thing I want is iguana jerky...

I appreciate any opinions.

.

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Scott Robert Ladd
1.0.0 Iguana (Rex)
1.0.0 African Giant Plated Lizard (Clyde)
1.0.0 Uro mali (Wizard)
0.1.0 Corn Snake (Amber)
1.1.0 Red-Eared Sliders (Jade and Emerald)
0.4.0 Homo sapiens (Maria, Elora, Becky, Tessa)
blog: http://chaoticcoyote.blogspot.com/

Is this just a typical household bulb? Not a mercury vapor bulb or anything like that?

I have seen diurnal lizards act differently when exposed to mercury vapor bulbs, no doubt. But in this case I gather it's just a reaction to the heat.

How long have you left the bulb on? 76* is pretty cold for an Iguana so your specimen may just be trying to warm up to it's desired temperature. Perhaps you're not leaving the bulb on long enough for this to happen? What is the longest period of time he's exposed himself to the bulb? Has he even left the heated area?

Regardless, from my experience with Iguanas I've always noticed that they will expose their heads to some surprisingly hot temperatures. I'm not overly suprised by what you describe.

A ceramic heat emitter might be a good idea. It will still provide a very hot area but will probably do a better job of distributing heat around the cage.
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Current snakes:

1.1 Gonyosoma oxycephala - (Silver/Yellow)

3.4 Gonyosoma oxycephala - (Green)

2.1 Gonyosoma janseni - (Black)

>> Is this just a typical household bulb? Not a mercury vapor
>> bulb or anything like that?

I broke the heat bulb for this fixture when building the cage, so we put a 100W "natural" household bulb in its place. I've switched to a 150W full-spectrum reptile bulb.

This is my first open cage, so I'm not certain of the temps. According to a thermometer, the basking spot is now at 97F, so he should be good to go.

>>How long have you left the bulb on? 76* is pretty cold for
>>an Iguana so your specimen may just be trying to warm up
>>to it's desired temperature.

That was my theory, but the light shining *through* his head was a bit disconcerting.

>>Regardless, from my experience with Iguanas I've always
>>noticed that they will expose their heads to some
>>surprisingly hot temperatures. I'm not overly suprised
>>by what you describe.

Sounds good. I just don;t want him to burn his eyes out or fry his brain.

Thanks.
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Scott Robert Ladd
1.0.0 Iguana (Rex)
1.0.0 African Giant Plated Lizard (Clyde)
1.0.0 Uro mali (Wizard)
0.1.0 Corn Snake (Amber)
1.1.0 Red-Eared Sliders (Jade and Emerald)
0.4.0 Homo sapiens (Maria, Elora, Becky, Tessa)
blog: http://chaoticcoyote.blogspot.com/

>>This is my first open cage, so I'm not certain of the temps. According to a thermometer, the basking spot is now at 97F, so he should be good to go.

He probably is. But ventilated cages in cool rooms can have very dramatic temperature shifts. It might be 97* where he basks, but how warm is it just 6" away? It could be surprisingly cool.

Iguanas will move to cool areas of a cage, no doubt, but they do seem to do better when there is a part of the cage that is "warm" rather than hot or cool.

I'd take a bunch of temps in different parts of the cage to be sure.
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Current snakes:

1.1 Gonyosoma oxycephala - (Silver/Yellow)

3.4 Gonyosoma oxycephala - (Green)

2.1 Gonyosoma janseni - (Black)

Rex is now quite happy with the 150W "full spectrum" bulb; no more weird hanging.

His baskiong spote is in the mid to upper 90s, the other end of his perch is in the mid 80s. At the bottom, more than three-feet below, the temp is running high 70s.
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Scott Robert Ladd
1.0.0 Iguana (Rex)
1.0.0 African Giant Plated Lizard (Clyde)
1.0.0 Uro mali (Wizard)
0.1.0 Corn Snake (Amber)
1.1.0 Red-Eared Sliders (Jade and Emerald)
0.4.0 Homo sapiens (Maria, Elora, Becky, Tessa)
blog: http://chaoticcoyote.blogspot.com/

I’ve seen a few lizards do this. It’s usually because they are trying to increase belly heat for digestion. Try putting a large flat stone under the light, it will absorb the heat and he will lie on top of it for belly warmth. Because you cage is mesh a fair amount of a 100w bulbs heat will dissipate, try a gauge under the basking spot to see what the actual temperature he is experiencing. Iguanas have a clear sense of thermoregulation and won’t expose themselves to excessive heat by choice. If he is that attracted to the heat lamp I’m guessing he is just a little cold.
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