There are 6 reptiles native to the UK and the adder is the only venomous one. It’s a cold climate specialist, and can be found within the Arctic Circle. Reports have even been made of these hardy snakes basking on top of snow during sunny spells! During the breeding season males will wrestle with each other for females, trying to pin the other to the ground without using their venomous bite. They are easily identified by a dark zig-zag pattern across the back and distinctive red eyes. They can be quite a chunky snake, reaching around 80cm.
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Where/when to find them
Adders can be found across a range of habitats including meadows, woodland, coastal slopes and scrubland. Heathlands, moorland and dune systems are particularly good habitats for them, providing basking spots, shelter and food sources. Male adders emerge from hibernation slightly earlier than females, and can be found from February onwards if the weather is mild. The snakes return to hibernacula (old mammal burrows, tree roots or rocky piles) to hibernate in late autumn.
The evolution of venom has made these snakes top predators of small creatures. Adders either ambush or search for their prey, injecting venom with a swift bite. They then track the bitten prey, using their super taste senses on their tongue to detect a scent trail.
Carnivores. They will eat any animal they can overpower and swallow, but mainly specialise in small mammals such as mice and voles. They will eat lizards, small birds and the occasional amphibian too.
Adders are in decline across the UK. Whilst they are very shy and bite only in self-defence, they still suffer from fear and persecution from humans. They are protected from killing or harm by law, but with habitat loss and increasing disturbance, some populations are at risk of extinction.