Control Of the Environment

No monitor lizard lives in an environment that never changes and most experience significant fluctuations in humidity, temperature and daylength over the year that have a profound effect on their behaviour. It is desirable to reproduce some of these seasonal changes in captivity in order to allow the lizards to approximate their natural cycles, but extremes must be avoided. Lizards that are forced to spend seven months of the year underground in their natural habitat do not necessarily benefit from having to do the same in captivity. Allowing some monitors to undergo periods of reduced or suspended activity appears to be essential for their well-being and reproducing seasonal changes in light and/or rainfall patterns can always be seen to have a beneficial effect. Working from the premise that in order to keep monitor lizards successfully every attempt must be made to reproduce their natural envirorunent it is obvious that careful attention needs to be given to simulating the natural cycles of the year as they occur in the animals' home countries. To this end data on temperature and rainfall in different areas of the world in inhabited by monitor lizards are given in Appendix III. They can be used in conjunction with data on daylength (e.g. Jones 1978) to reproduce seasonal changes but they are given as a guide only and must be used with great caution. The charts show the average temperatures recorded at meteorological stations in areas inhabited by monitor lizards. They do not show the temperatures experienced by the lizards, who carefully select cooler or warmer microclimates according to their inclination. The literal use of this data to determine the heat of the terrarium would often result in the death of its inhabitants.

Attribution / Courtesy: Daniel Bennett. 1995. A Little Book of Monitor Lizards. Viper Press U.K.