Adders are shy and secretive snakes. They don’t like to be too much in the open so they tend to hide in holes and crevices or in burrows made by other animals. Adders can often be found on heaths and moors. They can also be seen at the edge of woodlands, rocky hillsides, bushy slopes and hedgerows. Sometimes Adders live in marshes and bogs if dry ground is nearby.

Even though Adders can live in wet or dry environments, they need to be on dry ground when they want to hibernate. Hibernation is a long deep sleep during which the Adder’s heart beat and breathing slows down considerably. Before an Adder goes into hibernation, it has to store fat in its body. It lives off this body fat while it sleeps during the cold winter months.

Adders hibernate between November and February. Some Adders hibernate alone, while some Adders hibernate collectively with other Adders. They hibernate in burrows, under logs or in crevices in walls. The place the Adder chooses to hibernate in is called a ‘hibernaculum’.

Adders start to emerge out of hibernation around the end of February. They are very hungry after their long sleep so it is very important for them to find food at this stage as they need to build up body fat and energy again.

It is also very important for the Adder to bask in the sun. It has to absorb heat into the body because the body temperature needs to be high enough for the Adder to be able to digest food and function properly. The sun also regenerates vitamins into the Adder’s body which help it to become more active.