There are six species of native British reptiles and three of them are resident in the reserve: we have European adders (Vipera berus), grass snakes (Natrix natrix), and slow worms (Anguis fragilis).
All reptiles are cold blooded creatures and at this time of year, this far south, all three of these species should be looking for safe places to hibernate in our woodland and set-aside. Adders choose sheltered, dry spots: old rat or mouse burrows or holes in fallen trees where the warmth of the rotting wood keeps the temperature above freezing. Grass snakes will also choose animal burrows but share a taste with slow worms for the humidity of compost heaps and deep leaf litter among tree roots or rock piles.
Falling temperature is the most significant of the factors that trigger hibernation in reptiles. But reptile hibernation differs from mammalian hibernation in that snakes will wake from their sleep occasionally to drink and to sunbathe on warm days. As our climate has warmed and the number of warm sunny winter days has increased, these episodes of wakefulness have become more frequent.
This year, for the first time, adders have been confirmed as being active somewhere in the UK, at some time, in every month of the year.
Header image: Adder (Vipera berus) by Benny Trapp (CC-BY-3.0)