The adder (Vipera berus) is Britain's only venomous snake. Although bites are rare and seldom fatal, hospital treatment should always be sought. Adders are timid and retiring however, and will only bite if handled, cornered or trodden on.

Identification
The adder can be distinguished from the grass snake by the distinctive zigzag pattern, the vertical pupil and the often smaller and chunkier body.

Male adders are usually less than 60cm in length and have a lighter base colour with a more contrasting pattern. Females are usually less than 75cm and are more brown than the male.

Ecology
Adders feed mainly on lizards, small mammals and nestling birds. Adders are found in habitats including heaths, woodland edges, rough grassland and embankments. They bask in sunny spots close to dense cover such as heather, bracken or log piles. During the warmest months of the year they are often found in damp areas such as mires, bogs or wet heathland.

Adders in Buckinghamshire
Adders are very scarce in Bucks compared to other counties. The species has also been in decline across Britain. Adders prefer free draining chalky or sandy soils. Much of the county (the Ouse Valley and the Vale of Aylesbury) is made up of clay soils, which means the adder is limited in its distribution. The best places to find adders are on the Greensand Ridge (northeastern Bucks), the Chilterns (southeastern Bucks) and the glacial sands in the south of the county.

Increasing the number of adder records in the county is a priority of BucksARG.

Protection
It is illegal to kill, injure or trade adders under the Wildlife and Countryside Act 1981. Possession of adders is also controlled under the Dangerous Wild Animals Act 1976.