Adder

Britain's only venomous snake, this stocky reptile favours heathland, woodland edges, moorland, and coastal dunes where it can bask in sunny, sheltered spots. Look for the distinctive dark zigzag dorsal stripe running the length of the body, and watch for the characteristic slow, deliberate movement across open ground or the sudden coiling defensive posture if disturbed. The best time to observe is on calm, sunny mornings in spring, particularly March and April when individuals emerge from hibernation to bask and males engage in dramatic "dance of the adders" combat rituals — approach slowly and quietly from downwind to avoid triggering retreat into nearby vegetation.