Strictly come April …
The European Adder Vipera berus is the UK’s only native venomous snake and is widely but patchily distributed across the United Kingdom, particularly in England, Scotland, and parts of Wales. It favours downland, heathland, moorland, woodland edges, and coastal dunes, where a mix of cover and open basking areas supports its lifestyle. Despite its reputation, the Adder is shy and elusive, typically avoiding people and relying on camouflage to remain undetected.
Adders are relatively short and stout, usually measuring 60–80 cm in length. They are best recognised by the dark zigzag pattern running along the back, set against a grey, brown, or reddish background. Males are often lighter with more contrasting markings, while females tend to be darker brown. Both sexes have distinctive red or copper-toned eyes with vertical pupils, giving them a striking, almost feline appearance.
In the UK, Adders emerge from hibernation in early spring and are most active from March through October. Usually by mid-April, the males have shed their dull winter skins and enter a heightened state of activity linked to the breeding season. During warm, humid days there can be bursts of frenetic behaviour, with males actively searching for females and occasionally engaging in ritualised combat with rivals. These “dances” involve two males rearing up and intertwining, writhing around each other and sometimes covering the ground at surprising speed as they compete for mating opportunities.
Although venomous, bites are rare in the UK and are seldom serious, typically occurring only when a snake is disturbed or handled. The species is protected due to ongoing habitat loss and fragmentation, making conservation awareness important. Respecting their habitats, by sticking to paths and avoiding disturbance, helps ensure that this distinctive reptile continues to thrive as a part of Britain’s native wildlife.
References:
www.arc-trust.org/adder [Accessed, 11th April 2026].