Scotland has just one native snake: the adder (Vipera berus), also called the Common European Viper. It is Scotland’s only venomous snake. The UK’s other two native snakes, the grass snake and the smooth snake, are found in England and Wales but do not live wild in Scotland; occasional Scottish sightings of grass snakes are usually escaped pets rather than established populations.
The Adder
The adder (Vipera berus) is the only native snake species found in Scotland. It is a venomous viper that is relatively scarce, and can be found in a range of habitats including moorlands, heaths, and woodlands. The adder is known for the distinctive dark zigzag pattern along its back and its ability to change colour to blend with its surroundings. The IUCN Red List assessed the species as Least Concern in 2021, although UK populations are in long-term decline due to habitat loss.
The Grass Snake
The grass snake found across England and Wales is the barred grass snake (Natrix helvetica), which was split from the Eastern grass snake (Natrix natrix) as a separate species in 2017. It is non-venomous, can grow up to 1.5 metres in length, and is typically olive-green or brown with black markings. Grass snakes are strong swimmers and are often found near rivers, ponds, and other wetlands, where they feed mainly on amphibians and fish. They are not established in Scotland; any sightings north of the border are almost always escaped or released pets.
The Smooth Snake
The smooth snake (Coronella austriaca) is a non-venomous snake found across much of northern and central Europe. It grows to an average length of 60 to 75 cm and feels smooth to the touch thanks to its flat dorsal scales. Its colour pattern is usually a brown, grey, or reddish ground colour with rows of small dark spots and faint dark blotches along each flank. In the UK, the smooth snake is the rarest native reptile and is restricted to the lowland heaths of Dorset, Hampshire, and Surrey; it is not found in Scotland.
Conclusion
Scotland is home to a single snake species: the adder. The UK’s other two native snakes, the grass snake and the smooth snake, live in parts of England and Wales but not in Scotland. So if you see a snake on a Scottish walk, it is almost certainly an adder, and unless you handle it the bite risk is very low. Slow worms are also widespread in Scotland but are legless lizards, not snakes.
