Insight: The UK has three species of snake but only the Adder or Viper (Vipera berus) is venomous.
In spring they are commonly seen sunning themselves on rough pastureland and open woodland having just emerged from hibernation.
Both males and females have a dramatic, dark zigzag pattern extending down the entire length of their bodies. Males are normally lighter in colour and rarely exceed 60cms, while the larger female may reach 75cms and is a less obvious duller brown. However, there is an entirely black form, a Black Adder, that is not uncommon and can be mistaken for other species.
Adders rarely bite people unless provoked and their venom is not life threatening if treated.
Their diet consists mainly of small rodents such as voles and they can go for long periods of time without feeding.