©Jon Hawkins

Adder

Scientific name: Vipera berus
Our only venomous snake, the shy adder can be spotted basking in the sunshine in woodland glades and on heathlands. An adder bite is a very rare occurrence, and can be painful, but is almost never fatal.

Species information

Statistics

Length: 60-80cm
Weight: 50-100g
Average lifespan: up to 15 years

Conservation status

Protected in the UK under the Wildlife and Countryside Act, 1981. Priority Species under the UK Post-2010 Biodiversity Framework.

When to see

March to October

About

The adder is a relatively small, stocky snake that prefers woodland, heathland and moorland habitats. It hunts lizards and small mammals, as well as ground-nesting birds, such as skylark and meadow pipit. In spring, male adders perform a 'dance' during which they duel to fend off competition to mate. Females incubate the eggs internally, 'giving birth' to three to twenty live young. Adders hibernate from October, emerging in the first warm days of March, which is the easiest time of year to find them basking on a log or under a warm rock.

How to identify

The adder is a greyish snake, with a dark and very distinct zig-zag pattern down its back, and a red eye. Males tend to be more silvery-grey in colour, while females are more light or reddish-brown. Black (melanistic) forms are sometimes spotted.

Distribution

Found across the country, except for the Scottish islands, the Isles of Scilly, the Channel Islands, Northern Ireland and the Isle of Man.

Did you know?

The adder is the UK's only venomous snake, but its poison is generally of little danger to humans: an adder bite can be very painful and cause a nasty inflammation, but is really only dangerous to the very young, ill or old. If bitten, medical attention should be sought immediately, however. Adders are secretive animals and prefer to slither off into the undergrowth than confront and bite humans and domestic animals; most attacks happen when they are trodden on or picked up. Instead, they use their venom to immobilise and kill their prey of small mammals, nestlings and lizards.

How people can help

The Wildlife Trusts manage many nature reserves for the benefit of the wildlife they support. You can help by supporting your local Trust and becoming a member; you'll find out about exciting wildlife news, events on your doorstep and volunteering opportunities, and will be helping local wildlife along the way.