Written by Charles Bonnett, Transforming Lives Trainee
As the autumn chill sets in and the warm summer days recede, our native amphibians and reptiles begin the next chapter of their yearly journey: seeking shelter in which to overwinter.
Our reptiles and amphibians are ‘ectothermic’, which refers to their inability to produce their own body heat, instead depending on external sources to regulate their body temperature. This differs from ‘endothermic’ animals – such as mammals – who are able to internally regulate their own body temperature despite changing external conditions.
This ectothermic, cold-blooded characteristic means that, as the autumn sets in, seeking shelter to protect themselves from the cold climate is of primary importance. It is during this period that amphibians and reptiles enter a state of reduced physiological activity, known as ‘brumation.’ This state of dormancy is similar to hibernation, in that both involve extended periods of reduced activity to control energy consumption; however, whilst hibernating animals enter a deep sleep for the duration of the dormancy, brumation includes periods of intermittent activity through warmer periods.
Amphibians mostly overwinter on land, though a minority may choose to do so in water. They can achieve this amazing feat due to the permeability of their skin, through which they can absorb water and oxygen; this permeability, however, means that amphibians require a moist environment. Amphibians may overwinter in abandoned mammal burrows, compost heaps, loose soil, under rocks, or the bottom of ponds. Reptiles prefer dryer environments in which to overwinter; this may include unused mammal burrows, dead tree stumps, or leaf litter.
There are many ways you can help our amphibians and reptiles as the chill arrives:
- Build a hibernaculum to provide shelter for overwintering.
- Prepare your garden to support any reptiles and amphibians which may visit.
- Record any sightings on our free Dragon Finder App; any data is useful to help further understand the complex relationship between temperature and behaviour.