Butterfly Predators
The Adder
Vipera berus LINNAEUS, 1758
subfamily - VIPERINAE
Fully grown Adders are only interested in large prey such as mice, voles, shrews, lizards, frogs and slow worms. When young however they commonly eat the grass-feeding caterpillars of butterflies in the subfamilies Satyrinae and Hesperiinae. They also eat beetles, worms and spiders.
Adders are sadly becoming a rarity in Britain - partly as a result of habitat loss, which reduces the populations of it's prey, but also because of persecution by ill-informed individuals who believe it is dangerous and try to eradicate it.
In fact it is a very timid creature, and cases of attack on humans are extremely rare. The animal's instinctive reaction to human presence is to instantly slither away to a place of refuge, and it will only bite if you try to pick it up, or step on it bare-footed.

Adder, Vipera berus - Britain's only venomous snake  Adrian Hoskins

Adders inhabit dry sheltered and sunny sites which include woodland clearings, riverbanks, heaths, sand dunes and grasslands throughout Britain and Europe.

These beautiful snakes can be recognised by the distinctive dark zig-zag band along the back, and the V shaped mark behind the head. Males are silvery or pale brown with contrasting markings and grow to about 50-60cms in length. The females which are duller and less conspicuously marked can sometimes reach 80cms or more.

In spring, after awakening from hibernation adders can be found basking on logs, or in depressions in the ground, typically close to bushes.

Adders become sexually mature at the age of 3 or 4 years, and can live for up to 15 years. Mating takes place in April and May after a complex pre-nuptial ritual involving a great deal of side by side flowing movement, tail vibrations and body quivering. In early September the young are born live. Between 3-20 are born in each litter, and the young snakes are independent from birth. Often tiny adders, no more than 10cms long, can be found in early spring basking in sheltered depressions on the ground beside woodland paths or along railway cuttings.

Adders hunt chiefly by day. When hunting they continually flicker their forked tongues, with which they detect the scent of their prey. The quarry is bitten, and venom flows from the snake's hollow fangs and enters the victim's bloodstream. The venom contains a heart depressant which rapidly kills the prey which is then swallowed whole. The meal is slowly digested, and usually provides enough nourishment to enable the snake to live for about 7-10 days before it needs to feed again.

The bite of an adder is painful, but rarely causes death or hospitalisation of humans. Adders only attack humans if severely provoked - most victims of bites are over-adventurous teenagers trying to be "clever" by picking them up. Pet dogs are also occasionally bitten, but the effect is rarely fatal provided that they receive immediate veterinary treatment. If concerned, keep your pet on a lead, and don't let it roam in habitats known to contain Adders !



Contact  /  About me

Butterfly-watching holidays

Trip reports

UK latest sightings

Frequently asked questions

Strange but true !

Taxonomy & Evolution



Enemies of butterflies

Survival strategies

Migration & dispersal

Habitats - UK / Palaearctic

Habitats - Tropical rainforests

Butterfly world census

Butterflies of the World :

British Isles


Amazon & Andes

North America

temperate Asia


Indian subcontinent

Malaysia & Borneo

Papua New Guinea

Australia & N.Z.

Insects of Britain & Europe

Insects of Amazonia

Moths of the Andes

Saturniidae - Silkmoths

Caterpillars of the World

Butterfly Photography

Recommended Books



Code of practice

Copyright - text & images

Copyright - text & images






All photographs, artwork, text & website design are the property of Adrian Hoskins ( unless otherwise stated ) and are protected by Copyright. Photographs or text on this website must not be reproduced in part or in whole or published elsewhere without prior written consent of Adrian Hoskins / learnaboutbutterflies.com

Site hosted by Just Host