[Tehanu]

basically some amphibians skin is quite thin and while it allows the absorption water and a few other benefits higher levels of UVB lighting can be harmful, this is especially prevalent in certain nocturnal and certain terrestrial species, horned frogs hide on the bottom of rain forest floors digging into the earth this means they have very little exposure to UVB rays since they are convered by the canopy and has evoloved with little protection to UVB, there eye's are easily damaged as well. while 1 or 2 % probably wont do any harm its very unlikey (and there is no scientific proof that i know off) that UVB rays do them any good and anything over 4 or 5% can be quite harmful over mid to longer periods of exposure, so why bother having something that doesnt do them any harm and can possibly cause some harm

also albino's (as with all albinos) have a lower amount of the pigment that blacks UVB rays thus making the chances of damage more likely

to sum up they are in general a species that hasnt evolved to high level UVB exposure and being an albino just makes it worse

I'm going to have to get back to you on this one when I have more time!

Which species of Ceratophrys are we discussing?

Argentine Horned Frog (Ceratophrys ornata) - Draft report assessing the impact of importing live into Australian Zoos The habitat section may be of interest and is much more my perception of the adaptations of Ceratophrys sps.

Lotte***

 

[Tehanu]

man i just re read that, you can tell how knackered i was last night when i wrote it :blush:


probably ceratophrys cranwelli and/or ceratophrys ornata, i think most the stuff ive read about UVB damage to horned frogs relates mainly to C Ornata and albinos (which always are more easily damaged by UVB rays in any species)

:lol2:It may have been a little jumbled

So first things first, we need to clear up the environment and type of lifestyle for the commonly kept Ceratophrys. (For the benefit of all, so apologies for any over simplification!)

These frogs live a sedentry (sitting still the majority of the time!) lifestyle in open savannah areas (no rainforest canopy in sight!). For the drier parts of the year they may be burrowed into the soil fairly deep. When the wet season comes these frogs will spend weeks if not months sat in shallow pools or small puddles right there, in the open savannah, exposed to the sun and all it's glorious UV rays!!!

Amphibian skin may seem thin in comparison to our tough hides or if we compare them to scaley reptiles for instance, but they do have a keratinised skin which is delicate by comparison but not perhaps as "weak" as we might imagine.

Very high levels of UVB can be damaging to any living organism, the kind of levels we normally achieve in our vivaria with the average 5-10% UV tube are suitable for continuous use with amphibians, with due care taken to use a level suited to the species natural environment.
Clearly albino animals with UV requirements are a whole different kettle of fish!

As far as I'm aware there is no scientific evidence to suggest that normal (non-albino) Ceratophrys sps. have evolved with very little protection from UV rays, nor that their eyes are readily damaged, nor that a 5% UV tube can be "quite harmful" over time
Much as I loves you SpendDay, that is all purely conjecture :blush:

So, back to albinos.
Albinism in all animals has associated eye and skin problems. In short pigments in the skin and eyes offer some protection from light damage.

Cheers!
Lotte***