So brumation is an entirely natural phenomenon , from which a reptile will emerge with the arrival of spring . But it is also a very stressful process , and may prove fatal under extreme weather conditions , or if the animal concerned is poor in physical condition or weakened by virtue of its age ( either very young or old ). Brumation may also be linked with successful or enhanced reproduction , as cool temperatures are associated with spermatogenesis in the males , and seasonal cycling of the females .
So what do you do in captivity ? Well , first let ’ s deal with juvenile animals that have not previously experienced winter . Many of these do not fully brumate , but merely slow down a bit and consume less food . In captivity , it is therefore a simple matter to maintain warmer temperatures and day length and keep them active and growing through the colder months . In this way , they are given a ‘ kick start ’ and are likely to be significantly larger then wild juveniles come the next spring , without having undergone the rigours of winter .
Why don ’ t we just manage all our captive herps in this manner ? Well , some keepers do provide a ‘ summer regime ’ throughout the year , and depending on the species and individuals concerned , this may work well for them ( although not necessarily indefinitely ). However , periods of natural brumation may increase the longevity of your reptiles . Furthermore , the decision may not be yours to make , as your animals may switch into brumation of their own accord , independent of environmental cues . In southern Australia , captive reptiles have been known to commence brumation as early as February or March , at which time there would have been no detectable drop in photoperiod or temperature . In addition , if you wish to breed from your animals , a period of brumation is probably strongly advisable .
Not dead .... just dormant !
Brumation is used to avoid the extremes of winter , but what about when it gets too hot ? Aestivation is a similar form of dormancy employed by some reptiles and amphibians , together with a variety of invertebrates , to survive hot and dry weather . This is often assisted by holing up underground in cooler , more humid conditions . Western Australia ’ s Western Swamp Turtle ( Pseudemydura umbrina ) is notable for escaping the summer heat in this manner , and the Water-holding Frog ( Cyclorana platycephala ), which is widespread on the Australian mainland , buries itself in a cocoon of mucus , together with reserves of water stored in its skin and bladder . Aboriginals used the frog as a welcome source of drinkable water during extreme heat .
Dormancy can also be used to optimise the timing for new life . Many seeds remain inactive until germination is prompted by rising temperatures , moisture or fire . Similarly , hatching in some species of turtles ( and possibly monitors and crocodiles ) is delayed until flooding . Embryonic diapause ( in which the development of embryos is suspended pending appropriate conditions for hatching ) is also common amongst turtles and chameleons .
However , in captivity animals that are brumating need not experience the climatic extremes possible in the wild – or for quite the same duration . In most instances , the potential
Image by Kuttelvaserova Stuchelova .