For those curious about Scotland’s wildlife, a common question concerns venomous snakes. The answer is yes, Scotland has one native venomous snake species, the adder (Vipera berus). This reptile is the only venomous snake found across the entire United Kingdom.
Scotland’s Native Venomous Snake
The adder, or Vipera berus, is a relatively small and stocky snake, typically reaching lengths between 50 to 80 centimeters, with females often being larger than males. Its most recognizable feature is a distinct dark zigzag pattern running down the length of its back. Coloration varies; males are usually grey or silver with black markings, while females tend to be light brown, copper, or reddish-brown with dark brown markings. Some adders can also be entirely black, though the zigzag pattern might still be faintly visible in sunlight.
Adders possess a unique “V” or “X” shaped marking on their heads, and their eyes have vertical, slit pupils. Despite being venomous, adders are generally shy and non-aggressive. Bites usually occur only if the snake feels threatened, is accidentally stepped on, or is deliberately handled.
Where Adders Are Found
Adders are found throughout the Scottish mainland, favoring quiet, open areas such as:
- Heathland
- Moorland
- Woodland edges
- Peatlands
- Sand dunes
- Rough grassland
These snakes are widespread but can be locally rare in certain regions. They are absent from the Central Valley, Outer Hebrides, and Northern Isles.
Adders hibernate during the colder months, typically from October to March, in sheltered, dry locations like disused burrows or hollow logs. They emerge in early spring, usually March, and are most active during warmer months, from April to September. During this time, adders can often be seen basking in sunny spots to warm themselves, such as on rocks or logs. Their activity peaks in July and August, coinciding with increased outdoor human activity.
Safety and First Aid
Encounters with adders are uncommon as they are secretive. To minimize the risk of a bite, it is advisable to wear sturdy footwear and stick to marked paths when walking in adder habitats. Avoid disturbing adders if you see one, and keep dogs on a lead, especially near long grass or undergrowth where adders might be resting. Adders will often hiss as a warning if you are too close, indicating it is time to move away.
If an adder bite occurs, it is important to remain calm. Move away from the snake and seek immediate medical attention. Keep the bitten limb as still as possible and, if practical, keep it below the level of the heart to help slow venom dispersal. Remove any jewelry or tight clothing near the bite area in case of swelling.
Do not attempt to cut or suck the venom from the wound, apply a tourniquet, or use ice packs, as these actions can cause more harm than good. Wash the bite site gently with clean water. While adder bites are rarely fatal, they can cause pain, swelling, and inflammation, and professional medical assessment is always necessary, especially for children or the elderly, who may be more susceptible to severe reactions.