The venomous adder snake is to be admired, not feared
PUBLISHED: 10:59 07 June 2011 | UPDATED: 19:31 20 February 2013
Small but perfectly formed, our only venomous snake deserves admiration, not fear<br/>Words and pictures by Ann and Steve Toon
Two red eyes, narrow vertical slits for pupils, stare at us, unblinking. The snake is motionless, save for the occasional flick of a tiny forked tongue, tasting the air for hints of threat or danger.
Its a male, beautifully marked with a dark, almost black, zigzag pattern running down its back, flanked by rows of silver spots on a background of silvery grey. Dark stripes run along its cheeks and a bold, black, forward pointing V marks the crown of its head. V for viper, A for adder, depending on how you look at it.
The snake holds us transfixed, and not just by its graceful lines and exquisite markings. We know the statistics - youre more likely to be killed by a golf ball than an adder - and common sense tells us were quite safe so long as we treat the snake with respect.
But were a long way from a golf course, and theres a primal
fascination born of irrational fear that gives this encounter a frisson
Weve seen this snake dozens of times over the past few months, basking on the south-facing slope of a roadside ditch, just a few minutes stroll up the lane that runs by our Northumberland home. And hes rarely alone. On warm mornings weve counted up to half a dozen individuals along this short stretch of road, soaking up the suns rays to warm their cold-blooded bodies.
The uninformed or unappreciative might term this a nest of vipers. Adders get a bad press, and even today there are some folk in these parts with an old-fashioned country attitude to snakes - its illegal to
kill an adder, but persecution still goes on.
Our adder hotspot isnt really a nest, though, its the site of a hibernaculum, a subterranean hollow where groups of snakes can curl up and hibernate through the coldest months. Once spring arrives, the snakes emerge and initially at least dont venture far, but spend much of the time basking in sunshine.
This year we spotted our first adder on February 11th, a rare sunny day after weeks of bitter cold. It seemed surprisingly early for a cold-blooded creature to be out of hibernation, but adders are remarkably adaptable, as researcher James Stroud explains.
This species is the most widespread terrestrial snake in the world - its found from here all the way over to North Korea. It even stretches across the border into the arctic circle in northern Scandinavia - a true hardy generalist, he says.
James, an ecologist at the University of Hull, recently completed a two year project studying adders in commercial forestry plantations in the North York Moors national park.
In the UK adders are most strongly associated with southern heathlands, but there are good levels in the North East, he says.
Early in the year adders are just emerging from communal hibernacula - Ive seen up to eight basking on top of each other!), with the males emerging first to begin sperm production so that mating can occur as soon as the females wake up.
Adders are sexually dimorphic, so telling them apart is fairly easy, once you have managed to spot them, explains James. Males have black dorsal stripes, females brown. Females are also generally a little larger than males, though still smaller than many people realise, at only about 60cm long.
Late March to May is the breeding season for adders and the time to look out for the characteristic dance, once thought to be a courtship ritual between male and female, but actually a ritualised test of strength between rival males, in which they rear up and intertwine their bodies. When one eventually gives way the winner takes the prize, mating with the waiting female.
Females give birth in late summer or early autumn. The adders alternative name, viper, stems from the Latin vipera, a combination of vivus, meaning alive, and parere, meaning to give birth.
Unlike the much larger grass snake, which lay eggs, adders develop their eggs within their body, and give birth to live young, sometimes as many as twenty. This characteristic is probably what gave rise to an old myth about adders, that females swallow their young to protect them from danger.
Adders disperse away from the hibernacula to a separate feeding zone for the summer which is when it gets more difficult to see them, says James. Late summer/early autumn is your next best bet, as females need to extensively bask while gravid and the ensuing juveniles naively scatter themselves about everywhere.
The best weather is nice, clear sunny days, but be prepared to get out early to look. I have found snakes basking throughout the day, but the lower temperatures of early morning and early evenings mean more adders need to bask.
If youre keen to go adder spotting in the north east, then the best advice is to head for the hills. In County Durham adders are mainly found in mid-altitude moorland and forested sites skirting the Pennines, but not in the upper dales and moors.
Hamsterley Forest is a particular hotspot. In Northumberland they occur throughout the uplands, from Hadrians Wall to the Kyloe Hills north of Belford, and west to the Scottish border, as well as south of the Tyne in Allendale and the Devils Water fells area. Kielder Forest holds a good population.
A recent report from wildlife charity Amphibian and Reptile Conservation (ARC), giving interim results from a six year survey of the UKs reptiles, highlighted worrying concerns that the adder is in decline nationally.
Historically it was thought that deliberate persecution by man was the biggest threat to the species, but the ARC report suggests urban development, agricultural intensification, disturbance by countryside visitors, habitat fragmentation, and even inappropriate conservation management, may all be responsible.
With many adder populations now small and isolated, conservationists fear they may be increasingly vulnerable to disease and genetic defects. Now scientists from Natural England, the Zoological Society of London and Oxford University are to collect DNA samples from wild adders to study their genetic diversity.
Jim Foster, a reptile specialist for Natural England, explains: With around a third of adder populations now restricted to isolated pockets of habitat, and with only a handful of snakes per site, they could be especially vulnerable. Populations that are small and isolated can start to decline purely through genetic effects.
Fortunately, if there are problems we still have time to deploy a number of conservation remedies. Habitat restoration and the creation of wildlife corridors will help get these snakes back on the move. We may even consider moving adders between populations, to artificially promote gene flow - although that carries risks and wed need to look more closely at the genetics results before proceeding.
James Stroud says the adders decline is very worrying and that his own research suggests commercial forests may be a valuable future conservation refuge.
Anyone should feel extremely privileged to see them in the wild, they really are absolutely fascinating animals, he adds.
They are Britains only venomous snake, and having seen many species all over the world there is something truly unique about seeing them here in the wild.
Snakebite: the facts
Theres nothing madder than a trodden on Adder!, according to Spike Milligan, but the number of people actually bitten by adders in the UK each year is tiny, and fatalities are
According to Amphibian and Reptile Conservation there have only been around 12 cases of death from adder bite in the past century, and many more people have died from lighting strikes, wasp stings and stray golf balls.
Nonetheless, a bite can be very painful, and often ends up in hospitalisation, so if you do encounter an adder it pays to treat it with great respect and not approach too closely.
Keep dogs well away too, as an adder bite is a lot more likely to prove fatal to a dog. As James Stroud warns: Please dont touch them, it could seriously ruin your week.