ALAN GANE MBE looks at the flora and fauna of the Lake District. This issue: the adder

We are very fortunate in this country to have only one species of poisonous snake, that snake bites are rare, and that they are seldom fatal to humans. The one venomous snake we do have is the adder, or viper (Vivipera berus), the name ‘adder’ being from the old English ‘naedre’ or snake. However, it is worth bearing in mind that reports of adder sightings have been more frequent of late in this area. They have few predators, but are taken by buzzards and hedgehogs and the considerable decline in the hedgehog population may thus be a contributory factor in the increase of snake numbers.

The adder is a relatively stout snake, the adult measuring 50-80cms in length

Colour is very variable. Females are usually brown, sometimes a quite golden brown, while males are generally greyer. In addition, there are some which are black, or melanistic. Both sexes have a black zigzag marking along the back and a black ‘V’ on top of the head, but obviously this can be indistinct in melanistic individuals. The patterning can result in a very high degree of camouflage, especially among dead bracken.

Snakes are most likely to be seen basking in the sun on warm days

For safety’s sake, it is best to assume that any snake encountered may be an adder, and adopt the appropriate warning: do not touch! Adders are widely distributed throughout the UK and beyond, but distribution is relatively thin and sightings are not all that common. They occur in a range of habitats, such as heaths, woods and sand-dunes, in fact almost anywhere that is sunny and undisturbed. Only last April there was a case of snake bite in west London, when a father had seen an adder near his son and had brushed it away with his hand, only to be hospitalised for 24 hours as a result.

The adder has a pair of fangs which are normally folded, point backwards, one on each side of the upper jaw

The mouth can be opened very wide, so wide in fact that it can bite a vertical surface; as it is opened, the fangs swing down and as they do so venom is released and passes down a central channel of the fang towards the tip and, on biting, it is thus injected into the deepest part of the wound. There are often 80-90 snake bite cases a year in this country, but fatalities are rare; the most susceptible being the very young, the very old or those who are debilitated. Nevertheless, such a bite is a painful shock, reaction may be quite severe and hospital treatment is called for as soon as possible.

In the event of a bite, do NOT apply a tourniquet and do NOT attempt to suck the poison out

Such a bite may well be fatal to a dog. Adders are not aggressive, and will normally only strike if disturbed or threatened, being far more likely to move quite swiftly into cover if approached. They are very sensitive to vibration and heavy footfalls are enough to alert them. When approach is necessary, for observation or photography, if you are gentle and slow it is often possible to get quite close.

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