Adders are the only poisonous snakes that are found in the wild in Britain, making them something people need to be aware of if walking around the countryside.
They are especially common and widespread in the open areas of the New Forest and around rural Dorset areas.
Sadly, there are sometimes cases of dogs being bitten by adders in these areas, so it is important to be aware of key information.
If you want to know how to spot adders and what to do if you or your dog is bitten by one, then here's what you need to know.
The UK’s only venomous snake 🐍
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Vipera Berus (Common European Adder)
Have you ever seen a native UK snake? Visit the Wildwood Trust Adders this summer.#wildwoodtrust #wildwoodtrustkent #snake #adder #viper #ukwildlife #conservation #hythe #whiststable #canterbury #thanet pic.twitter.com/JzSFJdQ77d
Everything you need to know about adders in the UK
Where can adders be found?
According to the Wildlife Trust website, adders are usually found in woodland, heathland and moorland habitats.
How to spot an adder
The adder is a greyish snake with a dark and very distinct zig-zag pattern down its back, a red eye and a V-shaped marking on its head.
Males tend to be more silvery-grey in colour, while females are lighter or reddish-brown.
They can camouflage very effectively into their surroundings so it is unlikely that you will spot one, especially as in most cases they will move away if they detect an approach.

Adder bites are usually caused by them being trodden on accidentally or through them being picked up, so for extra care, keep an eye out when you are walking.
The European Adder is the only native venomous snake in the UK.
Are adders poisonous to humans or dogs?
On the New Forest National Park website, it states that adder bites or not usually poisonous to humans but can be to dogs.
It says: "Adders will only bite if they feel threatened or are provoked. Bites to humans are rarely life-threatening but medical attention should be sought. If your dog is bitten by an adder, take it to a vet immediately."
Adders hibernate between October and March, so it is during the in-between summer period when this slight risk may arise.
Additionally, adders are protected in the UK under the Wildlife and Countryside Act, 1981, so it is illegal to intentionally kill or injure them.
Priory Veterinary Group vet Marcus Willcock said an adder's venom is at its most potent during late spring and early summer as temperatures rise and adders become increasingly mobile.
In terms of treatment for dogs, timing is the most important factor.
Adder bites can be dangerous for dogs (Image: Colin Moyes/Dorset Camera Club)
Mr Willcock said: "If you suspect that your dog has been bitten by an adder, if any sudden and significant swelling, pain or bruising becomes apparent on your pet during a walk, then it is vital to contact your vets immediately.
He said the use of anti-venom will be carefully considered based on a number of factors, including the location of the bite, the severity of the symptoms and any financial constraints.
The vet added: "It is important to note that the use of venom may be avoided if there is any uncertainty that an adder has caused the injury, so it may help if you take a picture of the culprit to help with identification.
Recommended reading:
- Full list of every snake found in UK gardens and if they are dangerous
- How to tell the difference between adders, grass snakes and smooth snakes?
- Have adders ever killed anyone in the UK? 100 reported bites each year
"Its use will generally ensure a more rapid recovery time and reduce the severity of any symptoms incurred, but many animals can improve without its use.
"Although very rare, more serious cases can result in convulsions, collapse and kidney or liver injury.
"Therefore, it is important to monitor these parameters within the first 24 hours, and once this has passed the swelling can take up to 7 days to return to normal. If the appropriate treatment is instigated within an adequate time frame, the majority of adder bites are not fatal."
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