Gloucestershire is home to a range of wildlife and threatened species from large blue butterflies and water voles, to pine martens and curlews. One endangered species that calls this county (and the Cotswolds) home is the UK’s only venomous snake, the adder.

Adders spend the coldest part of the year hibernating in sheltered places, from about October to the start of March. After emerging in early March, adders need to bask in warm spots to build up their energy, particularly male adders as this is essential for them to mate.

In spring, male adders fend off competition and perform a ‘dance’, females will then mate with the best and strongest ‘dancers’ who are ahead of the competition. Other reptiles lay eggs which will be incubated and hatch outside of the body, but female adders incubate eggs internally, before ‘giving birth’ to between three and twenty live young towards the end of summer.

These secretive snakes can live for up to fifteen years, and are relatively small and stocky, with a length of 60-80cm and a weight of 50-100g. They are greyish in colour and have a dark and distinct zig-zag pattern down their backs. Like our fingerprints, they have markings on their heads, which can be used to tell individuals apart.

Too many disturbances to adders, especially when they are building up their strength in the sun, can be a threat to this endangered species. Needing to move and hide too often uses energy that could be used to catch food that day. Unfortunately, disturbance and a lack of proper protection have led to the decline of adders across the UK.

Now, adders are protected in the UK, but still face threats from habitat loss, disturbance, fragmentation, and predation. Gloucestershire is one of few remaining strongholds for adders in the UK.

Gloucestershire Wildlife Trust’s Head of Nature Recovery Zones, Ian Stevenson said;

Great British Life: Adders tend to be very elusive. Photo: Chris LawrenceAdders tend to be very elusive. Photo: Chris Lawrence

“If you see an adder, you’re lucky. Adders are an endangered species and our neighbouring counties have already lost these elusive and important creatures. It’s really important that we try to protect our remaining adders for future generations to see, and to keep adders as a piece in the puzzle of ecosystems.”

Adders rarely bite humans and domestic animals, despite being venomous, Ian explained;

“They’re shy snakes and would rather hide than attack, instead they use their venom to hunt and catch their prey, consisting of small animals, nestlings, and even lizards.”

READ MORE: How to spot the difference between an adder and a grass snake

Adder venom is generally of little danger to humans, but it can be painful and cause inflammation, and can be dangerous to the very young, ill or old.

Most bites happen when adders are trodden on or picked up. To help protect this endangered species, and prevent an accident, please avoid disturbing them and keep your dog on a lead. If you or your dog are bitten by a snake, please seek medical attention immediately.

If you spot an adder - or any other species - you can report your sighting to the Gloucestershire Centre for Environmental Records (GCER). This will add to the growing database of information about wild plants, animals and habitats in Gloucestershire, underpinning the evidence which Gloucestershire Wildlife Trust needs in order to prioritise and carry out its important conservation work.

Next time you’re out for a stroll amongst the beautiful Cotswold grasslands or are wandering through a shady glade, keep your eyes peeled for this elusive but wonderful species.