Interesting article about lighting for invertebrate/scorpion enclosures

Have just been reading through the last issue of Practical Reptile Keeping magazine Novemeber 2010 (its a UK mag) and there is an article on providing the right kind of lighting for invertebrate enclosures. The author claims that using 2% UV Reptile Lighting tubes above scorpion and tarantula enclosures is beneficial. He writes about setting up naturalistic enclosures lit by two flourescent tubes, a Grolux lamp developed for planted aquariums and a lamp developed for reptiles that emits 2% UVA, the former is used to aid the growth of live plants in his enclosures and the latter he says provides a more natural spectrum of light for his invertebrates and plants.
He goes on to talk about how it is 'recognised that the UVA component of Ultraviolet light plays an important role in aiding both the sight and general well being of invertebrates'. He then talks about how he himself has observed his own Chile Rose Tarantulas and Emperor Scorpions 'basking' under the rays emitted by the lights.

His enclosures are heavily planted so the there are covered areas underneath leaves, burrows etc. where the animals will not be exposed to the UVA quote 'the UV passing down through the vegetation is provided in the same gentle, diffused way as in the wild'. The lighting is timed to provide a natural photoperiod so the enclosure is not exposed to a UV source 24/7. His ideas behind using this kind of lighting coupled with the correct photoperiod of the animals country of origin, is that it simulates a more natural light which will hopefully produce more natural behaviour in his animals i.e. aid in scorpion breeding/ differentiating between the sexes etc. We already know that some animals use UV light to find prey i.e. the kestrel following UV reflecting vole urine and differntiating between sexes i.e. sexually different coloured plumage in some birds.

For me this article was of great interest as i enjoy creating naturalistic enclosures and the lighting he uses is perfect for growing plants but I have read alot of articles stating that prelonged exposure to UV light is dangerous for scorpions. The way his enclosures are designed provide the animal with plenty of opportunities to hide (i.e. burrows, rocks) so will therefore not be constantly exposed to the UV and the lighting will be switched off at night so there will be no chance of exposure then.
Surely this is about the closest you can get to provide 'natural' light in your enclosure?
Anyway I'd love to hear what people have got to say on all this. Is it a good idea? Has anyone used similar lighting before? Does this guy even know what he is talking about? Have people got it all wrong about not using any form of UV light in a scorpion enclosure? Would it aid breeding attempts?
Cheers, Callum

"He then talks about how he himself has observed his own Chile Rose Tarantulas and Emperor Scorpions 'basking' under the rays emitted by the lights."

Well, I would have to read the article but invertebrates don't "bask" in rays of anything except heat and to my knowledge there is no study showing otherwise. From what you just said it seems like that guy was saying that they were basking in the UVA and not the heat. I used to have a heat rock for reptiles that my emps used to lay on in the same way they bask in my lamp heat on one side of the enclosure.

"Does this guy even know what he is talking about?"

I don't think he's studied it enough, in my opinion he's just stating a hypothesis that has yet to be tested. UV lighting is known to be harmful to invertebrates so i'm skeptical to his reasoning with being natural, for all he knows it's the UVA that in the wild species is what makes them not live as long as in a UVA free enclosure.

"Would it aid breeding attempts?``

I personally do not think so since most breeding attempts in the wild most likely come at night when there is no UV light (or very little). Scorpions are nocturnal by nature, I do not believe the author fully understood this when he implicated that it might help with breeding or anything else. Though i`m fully aware that scorpions do come out during the day and there are some that do do a good portion of their activity during daytime I`m still very skeptical and would need to see more research and testing to verify this hypothesis before I even consider exposing my collection to any kind of UV lighting.

to me it make sense to make the viv as natural as possible. I personally have all my viv's from my 7' jungle carpet python to my Haitian brown tarantula to my emps all on timered lighting .. now the scorpions are not getting uv light other then what come in thru the windows...but the frogs and snake get natural.. aka full spectrum uv.. same with the turtles.. I keep live plants in my vivs for a more natural look and feel for the animal...