Vipera berus - Common viper:

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Summary Information
Living Organisms / Animalia / Craniata / Reptilia / Squamata / Viperidae / Vipera / Species
Alternative Names
  • Vipera berus berus
  • Adder
  • Northern viper
  • Vipere (French)
  • Kreuzotter (German)
Description Length:
  • Total usually up to 65cm, exceptionally may be nearly 90cm; females generally larger than males (B159).
  • Newborn: about 16.0cm (B160)
  • By first hibernation: about 17.0cm (B160)
  • One year: 26.0cm(B160)
  • Two years 35.0cm (B160)


  • Heavy-bodied snake with short tail, well-defined triangular head, constricted neck
  • Small eye with vertical pupil, no eyelids,
  • Dorsal body scales strongly keeled. 
  • Snout flat (not upturned), almost always several large scales on top of head, single row of small scales (subocular scales) below eye.
  • Mid-body usually has 21 dorsal rows of scales. 
  • (B159, B160)

General description:


  • Usually clearly marked zig-zag vertebral stripe. Rarely has distinct central paler band, is straight-edged, broken, faint or absent.
  • Often also smaller round/oval spots along sides.
  • Head may be black; often dark chevron or "X" shape. 
  • Dark streak from eye to commisure of jaw and sometimes backwards onto neck.
  • Lips whitish or yellow.
  • Throat white/yellow, with brown/black markings, often more in male.
  • Iris copper-coloured, pupil vertical.
  • Males usually pale grey/whitish/cream/light olive with markings of intense black.
  • Females usually brownish/reddish/golden with dark brown markings.
  • Abdomen: grey-blue/grey/grey-brown/black; sometimes with pale/white spots or stippling
  • Tail tip ventrally may be yellow orange or red.
  • (B159, B160)


  • All-black.
  • Abdomen blue.
  • Balkans: more variable. Back may be marked with cross bars. May have two rows of scales below eye.
  • North-western Iberia: vertebral stripe may be straight, wavy or zig-zaged, with paler centre sometimes wide enough to reduce dark areas to series of spots on either side of pale line.

Similar species and distinguishing features:

  • Distinguished from Vipera aspis by lack of clear upturn on snout, single row (usually) of scales below eye, central head scales not fragmented. (B159)
  • In Britain: distinguished by relatively thick, heavy body, short tail, vertical pupil, large head; also by patterning (B160)
Range and Habitat Range:
  • Most of Europe, north to beyond Arctic Circle, southwards to north-western Spain, northern Italy, much of northern Balkans. Central Europe and southern areas rather sporadic. Eastwards across former USSR to Pacific coast and Sakhalin. (B159, B160)
  • Britain: England, Wales and Scotland; Isle of Wight and Anglesey, but not Isle of Man (B160)
  • Not found in Ireland (B160).


  • Various habitats, including moorlands, heaths, dunes, bogs, open woodland, field edges, hedgerows, marshy meadows, saltmarsh.
  • In south: mainly in mountain areas, up to about 3000m in Alps; also in moist areas of lowlands e.g. in northern Italy.

(B159, B160)

Further Information Activity: 
  • Mainly diurnal. 
  • Relatively slow moving. 
  • Swim well.
  • Bask mainly in early morning
  • (B159, B160)

NB. venomous. most likely to strike if alarmed e.g. by sudden movement (B160)


  • In holes/cavities in the ground
  • Start hibernation in October in Britain 
  • May be alone or in groups
  • Emerge as early as February


  • Live young (B159)
  • Mating April/early May
  • Males may engage in "dance" of rivalry.
  • Mating: may last several hours (B160).
  • Birth August to September
  • Oestrous period several days B160
  • Number of eggs/young: 6-20; usually 10-14 (B160)
  • Rupture membrane by convulsive body movements and final forward thrust of head (B160)
  • Males sexually mature when reach about 40.0cm (B160)
  • Females start to develop eggs in fourth year, first young born when five years old, about 47.0cm (B160)
  • Newborn young may shelter under the female (B160)


  • Mainly small mammals, also lizards (B159)
  • Lizards, also mammals such as mice, voles, shrews, bird eggs, nestling birds, frogs, newts, slugs, worms, insects (B160)
  • Juveniles probably eat mainly insects, spiders, worms (B160)


  • Often hunt from cover.
  • Strike rapidly, injecting venom and releasing, then tracking prey
  • May eat amphibians without killing them first.
  • (B159, B160)

Skin shedding: 

  • Whole skin usually shed at one time, in one or several pieces. eye becomes opaque prior to skin casting (B160)


  • Predatory birds
  • Hedgehogs
  • Foxes
  • Pike, eels
  • (B160)

Organisations (UK Contacts):

Electronic Library (further reading):

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General Legislation:

Individual techniques:

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