Butterfly Predators
The Adder
Vipera berus
LINNAEUS, 1758
Family - VIPERIDAE
subfamily -
VIPERINAE
The Adder in the photo below seems
to be taking an interest in the caterpillar on the stem. When
young, they commonly eat caterpillars, so can be considered as
low-threat predators of Lepidoptera. The young Adders also eat beetles, worms and spiders, but
fully grown adults such as this one are only interested in larger prey such as mice, voles, shrews,
lizards, frogs and slow worms.
This beautiful creature is 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.
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Adder,
Vipera berus - Britain's only
venomous snake |
Adders inhabit
dry, sheltered and sunny sites which include woodland clearings,
river-banks,
heaths, sand dunes and grasslands
throughout Britain and Europe.
They can be
recognised by the distinctive dark zigzag banding along the back,
and the V shaped mark behind the head. Males are silvery or pale
brown with contrasting markings, whereas females are duller and
less conspicuously marked. Males grow to a maximum of about 60cms
in length, while females can reach 80cms or more.
In spring, after
awakening from hibernation they can be found basking on logs, or
in depressions in the ground, typically close to bushes.
The snakes 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 3 or 4 inches in length, can be found in
early spring by searching woodland banks, railway cuttings and
similar sheltered habitats. Although very small, they already have
full venom sacs, so should not be handled.
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 very painful, but very rarely causes death or
hospitalisation of humans. The snakes do not attack humans unless
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 do not let it roam in habitats known
to contain Adders !
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