Ben Dessen refers to himself as a ‘ conservationist and wildlife advocate ’ but he is also Reptiles Department Manager at Kellyville Pets and is passionate about educating newcomers to the reptile hobby . Here he focuses on the importance of appropriate lighting ; a topic which is often overlooked or misunderstood .
Let there be Light !
A wild reptile or amphibian ’ s daily existence is driven by their need for exposure to solar heat and light in order to maintain healthy bodily functions . As reptile keepers , it is essential that we strive to replicate an animal ’ s natural environment as closely as possible through the use of artificial heating and lighting devices . In Issue Two , the importance of providing optimal temperature gradients within a reptile ’ s enclosure was outlined , along with some of the most effective methods for providing heat to captive reptiles . Arguably , the second most critical consideration when setting up an artificial reptile environment is the animal ’ s need for suitable lighting , which varies between species .
In order to thermoregulate a reptile must bask in the sun , or absorb heat from a warm surface such as a rock or log . Whilst a reptile basks , it is not only absorbing the sun ’ s solar energy , or heat , but also the ultraviolet ( UV ) light that is a normal component of natural sunlight . Ultraviolet light can be divided into a number of types depending on its particular wavelength . Ultraviolet A light , commonly referred to as UVA , has a wavelength of 320-400nm and is known to have beneficial effects on many reptiles , promoting healthy levels of activities such as feeding , foraging , basking and reproduction . UVB light ( 290-320nm ) play a vital role in the production of vitamin D 3 , which in turn controls calcium absorption from the gut ( calcium is necessary for strong bones and normal neurological function ). UVB also directly affects reptiles ’ skin by strengthening scales as well as promoting pigment formation , which will ultimately determine colouration . UVC light has a shorter wavelength ( 100-280nm ) and is dangerous to living tissue . Fortunately , it is wholly absorbed by the atmosphere .
The intensity of UV in natural sunlight varies according to cloud cover and the time of day , but is greatest around midday when the sun reaches its highest point in the sky . Different species of reptiles will absorb different doses of UV light depending on their natural patterns of activity , basking behaviours and habitat . A reptile ’ s natural UV exposure can be categorised into one of four ‘ zones ’ based upon its thermoregulatory behaviour and preferences for taking shelter during the day : crepuscular / shade dweller ; partial-sun / occasional basker ; open / partialsun basker ; and midday full-sun basker . It is a crucial aspect of reptile care to understand your animal ’ s natural behaviours in order to replicate its specific lighting requirements . Remember also that visible light intensity may assist a reptile by providing cues for thermoregulation , since heat and light are naturally associated with each other .
Artificial UV lighting .
Many captive reptiles have an unquestionable requirement for some form of artificial UV lighting in order to maintain normal development and function . However , whether it is essential for some species , like nocturnal geckos and pythons , remains contentious . Some keepers maintain that these animals thrive on dietary calcium and vitamin D 3 alone . It is important to recognise that just because an animal can survive without exposure to UV light , this does not necessarily mean that it won ’ t benefit from it . For example , UVA is visible to most reptiles , and may be important in the recognition of other animals , plants and food items . Furthermore , geckos – like many reptiles – are known to behave differently when exposed to UV light . Research is ongoing , however , for the majority of reptile species , the provision of UV light is strongly recommended –
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