Grass snake The grass snake is our longest snake, but don't worry if you find one in the compost heap - it's harmless! Look out for this green and yellow beauty in grasslands and wetlands, too.
Scientific name
Natrix helvetica
When to see
April to October
Species information
Category
Reptiles
Statistics
Length: 90-150cm Weight: 240g Average lifespan: 15-25 years
Conservation status
Protected in the UK under the Wildlife and Countryside Act, 1981. Priority Species under the UK Post-2010 Biodiversity Framework.
Habitats
Grassland
Heathland and moorland
Freshwater
Farmland
Wetlands
Woodland
About
Our largest snake, the grass snake, is particularly fond of wetland habitats, but can also be found in dry grasslands and in gardens, especially those with a pond nearby. During the summer, grass snake can be spotted basking in the sun near their favourite ponds or swimming in the water. They hunt amphibians, fish, small mammals and birds. Females lay 10 to 40 eggs in rotting vegetation, such as compost heaps, incubating them until they hatch in early Autumn. Like all reptiles, grass snake hibernate, usually from October to April. Note The British population of grass snake belongs to the distinct subspecies natrix natrix helvetica, but new research published in August 2017 proposed that it should be elevated to full species status, with the name barred grass snake, natrix helvetica.
How to identify
The grass snake is usually greenish in colour, with a yellow and black collar, pale belly, and dark markings down the sides. Females are bigger than males.
Distribution
Widespread in England and Wales, but absent from Scotland, Northern Ireland, the Isles of Scilly and most of the Channel Islands (they are found on Jersey).
Did you know?
When threatened by one of its many predators, the grass snake often 'plays dead', perhaps making itself less appealing to eat. Predators include badgers, red foxes, domestic cats, hedgehogs and a number of birds; when caught, grass snakes hiss and release a foul-smelling substance from their anal gland. Although they may also strike with the head, they do not bite and are harmless to humans.
Watch
Grass snake (https://vimeo.com/646956073)
Russell Savory
Identify UK snakes
Grass snake or adder? The UK has three species of grass snake, adder and smooth snake. Want to know how to identify British snakes? Read…
Species
Adder
Our only venomous snake, the shy adder can be spotted basking in the sunshine in woodland glades and on heathlands.
Reptiles
The UK's 6 native species of reptile are often overlooked when thinking about British wildlife. Find out the best places to see…
Bob Coyle
Our gardens are vital for wildlife
The UK's gardens provide more space for nature than all the National Nature Reserves put together.
Wildlife-friendly gardening
As a charity we rely on memberships
They help us look after over 2,300 nature reserves and protect the animals that call them home.
Species 
