Spring is the perfect time to spot one of our most misunderstood and threatened creatures . . .
As the days lengthen and the sun warms the soil, adders are emerging from their winter lairs to bask on rocks across the country.
This is when our only venomous snake is now at its most conspicuous, for this is the mating season. Females grow up to two feet, males are a little smaller. Colours vary from black and white to browny-green. Most have a diamond pattern.
The snakes wil have spent the last five or six months underground, often communally, ‘brumating’’ (instead of full hibernation, their body temperature drops, but they stay awake, moving slowly to keep warm). In late March they emerge, however, and the smaller males vie to attract females, performing strange ‘dances’ when two rivals test each other’s strength by rearing up and leaning on the other.
Within a few weeks they will have mated and dispersed when they will be far more difficult to spot as they hunt voles on their own in tussocky pasture and along woodland rides. The young are born live five months later in August. The youngsters are armed with venom from birth, but at first feed mainly on insects, switching to voles as they grow.
Sadly adders are in decline across Britain. A build-up of pesticides in the lower food chain is one threat, but habitat destruction is the biggest problem. Adders need rough grass to hunt for voles while hiding from predators. Over-grazing by sheep coupled with a soaring buzzard population thus presents them with a ‘double whammy’ of less food coupled with less cover.
Human persecution is another problem. Despite strict protection, hundreds are killed illegally each year by humans “in self-defence” (the National Poisons Unit says almost all the referrals they get each year are young men who have been bitten on the hands).
Contrary to popular belief, adder venom is fairly harmless to humans and rarely much worse than a wasp sting. The last British fatality was a five year-old in 1977, but the cause of death was really anaphylactic shock rather than genuine envenomation.
Far more people die annually from insect stings and allergies than are killed by adders in a century. In practice they only strike when pushed:
While it remains our commonest snake, found from Dorset heaths to the Highlands, its distribution is very fragmented and localised. As a result, when a small colony disappears, reclaiming the lost ground can be almost impossible. This leaves it confined to ‘islands’ of suitable habitat. Notable ‘hot spots’ include the New and Wyre Forests, but in Wales the best places to find the creatures is in Pembrokeshire or on Tregaron Bog or Nant-yr-Arian near Aberystwyth.
