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The Adder (Vipera Berus) is Britain’s only poisonous snake and is the only snake found in Scotland. The other common varieties, the grass snake and the smooth snake, are confined to England and Wales. Adders are timid by nature and will use their exceptional camouflage to avoid being spotted or disappear into the bushes and undergrowth at speed if they feel the vibrations of a threat approaching. While the adder is thought to have claimed the lives of around 10 people within the last 100 years or so, modern knowledge about snake bites and good access to medical care have greatly reduced the threat they pose to life. Only those that are susceptible to anaphylactic shock are at major risk.

Adders can be found in a very wide range of habitats but open ground such as moors and grasslands are a favourite as they are often full of their prey; usually small mammals such as mice and voles. They will also eat eggs, birds, frogs and other occasional unlucky animals. This liking for open ground is often where they come into contact with humans out walking or working the land. Early Spring is a good time to see them if the weather is warm as the males will be out looking for a mate and can often be seen basking in the sunshine on a rock.

Adders grow to around 90cm but are generally smaller, especially where the climate is colder. They have a grey/brown body with a very distinctive black zigzag pattern on their back. Occasionally the snakes can be completely black. Females are generally lighter in colour with a dark brown zigzag although it can be difficult to tell the difference.

The female will give birth to between 5 and 20 live young which are around 15cm long at birth. These snakes are immediately left to fend for themselves and go into hibernation quite soon after birth, often not eating until into their second year.

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