Vipera berus - Northern European Adder
"Some by-our-lady fool once said that you could tell an adder because it had a 'V' on its head, which stood for Viper. It would take you five minutes to find the mark on an adder's head anyway, but [the grass snakes] with their bright yellow black-bordered 'V' get bashed to death in consequence"
T.H. White, "The Sword in the Stone"
The poor adder suffers from Man more than Man does from its poison - sadly, in part because of his (mostly ungrounded) fears, the adder's greatest enemy is Man. Sometimes known as the viper, this snake is the only poisonous snake native to Britain. Also to be found in Scandinavia, and the only snake native to Scotland, the adder is unusual in that it is viviparous, the eggs being hatched in the mother's body, and the young snakes being born in August. This method enables the adder to live in colder climes, where oviparous reptiles would have a tougher time hatching their eggs.
Orginally known as "nadder", the adder is a handsome beast, growing to around two feet (55cm) in length, with dark (male) and brown (female) zig-zag or diamond markings. Easily distinguished from the grass snake by its arrow-shaped head and darker colours, its preferred habitat is open heathland, where it can find hiding places in the dense ground cover. Naturally shy, they will quickly move out of the way when they hear anything move toward them, and they are certainly more frightened of us than we are of them, and with good reason. (In the Nordic countries, "about 10% of adders don't have the diamond / zigzag markings, but they are completely dark brown or black.")
Their diet includes almost any vertebrate smaller than them - voles, mice, lizards and shrews being typical. Hunting by scent, they track their prey before striking. If necessary, they follow the dying animal until its demise. In addition to being the predator, however, they themselves are predated upon - usually by birds of prey such as eagles and the larger hawks, although herons are also said to take the younger snakes. Hedgehogs may also take snakes, biting and curling up until the snake is exhausted, then delivering the coup de grace.
They hibernate where they can - underground if possible, but any deep sheltered crevice will suffice. The hibernation season lasts from October to February, and they may also form hibernation communes, with as many as 40 snakes coiled together to avoid being frozen.
The venom is painful to humans, though seldom fatal. With around a dozen reported deaths in the past century, you are more likely to be killed by lightning or a golf ball, than by an adder's bite. Anti-venom is available, and victims of bites should be taken with all speed to medical facilities.
The Real Threat
As mentioned earlier, Man represents the greatest threat to this timid creature. The destruction of its habitat, and reducing numbers of its prey have reduced numbers in England and Scotland, at least - they are now protected under Wildlife and Countryside Act and it is now illegal to kill, injure or sell them.
On a personal note, I recently saw an adder on the moors above Wooller in Northumberland. True to form, directly it detected me, it poured away into the heather to hide, but I caught enough of a glimpse of this delightful creature to appreciate its beauty.
Not to be confused with the full adder which is a logic component. Snakes would not make good computer components.
SharQ helped :)
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