The Effect of Different UV and Calcium Provisioning on Health and Fitness Traits of Red-eyed Tree Frogs (Agalychnis callidryas)

Abstract. In response to global amphibian declines and extnctons, the IUCN has recommended the establishment of ex situ conservaton breeding programmes. However, there are a limited number of studies that scientfcally assess amphibian husbandry practces, even at a basic level of nutriton and lightng. One component of captve husbandry that is increasingly discussed is the provision of ultraviolet radiaton (UVR), which is required for the synthesis of vitamin D3 and subsequent assimilaton of calcium and phosphorous from the diet. Here we used two methods of UV provision (“background UV” and “background UV with UV boost”) and two calcium gut-loading diets (5% and 10%) to assess the effects on a range of ftness measures in the red-eyed tree frog (Agalychnis callidryas). We found no effects of
either UV treatment or calcium diet on growth, body conditon or cutaneous bacterial communites of frogs, although subsequent to the UV boost, frogs had a signifcantly greater fungal load in comparison to frogs that were not UV-boosted. There were negligible differences in the breeding success of females according to UV exposure. Provision of the UV boost was not demonstrated to provide any real advantages for A. callidryas in terms of growth or breeding success. In additon, there were no benefts of a 10% calcium diet over a 5% calcium diet (in conjuncton with regular dustng). Further studies that investgate the UV requirements of other amphibian species and ecotypes are required, partcularly in conjuncton with naturalistc cricket gut-loading diets.