There have been a number of adders sightings across the UK in recent months resulting in the deaths of numerous dogs.

There are only three types of snakes native to the UK - an adder, grass snake and a smooth snake.

Adders are the most dangerous as they are the only venomous one out of the three.

Vets have urged dog owners to be on the lookout for adders.

Although, it's important to note that they are most active during the warmer months since this is when they become "increasingly mobile". 

Glasgow Times: The adder is the only venomous snake native to the UK.The adder is the only venomous snake native to the UK. (Image: Getty Images)

If you suspect your dog has been bitten by an adder it is important to get your four-legged friend to your local vet immediately.

So how do you tell the difference between an adder and a grass or smooth snake?

The difference between an adder, grass snake and smooth snake 

Adder

According to the RSPCA, an adder has a "distinctive zig-zag pattern down his/her back, with red eyes and a vertical pupil". 

They can grow up to around 70cm.

The RSPCA adds: "They're the only venomous species of snake in the UK!"

Grass snake

Glasgow Times: There are three types of snakes native to the UK - the adder, grass snake (pictured) and smooth snake.There are three types of snakes native to the UK - the adder, grass snake (pictured) and smooth snake. (Image: Getty Images)

In comparison, grass snakes are usually an "olive green colour, with large eyes and round pupils". 

Grass snakes can grow to be over a meter long.

The RSPCA added: "They have a distinct collar behind their heads and are also the only native snake species to lay eggs.

"If you're lucky, this species might visit your garden (look out for soft leathery eggs in your compost heap!)."

Smooth snake

The smooth snake is the least widespread according to the RSPCA and is localised to the south of England, mainly found in heath habitats.

It is the smallest species, growing to only around 55cm in length.

The RSPCA added: "They're typically a greyish brown in colour, have a dark stripe down the side of their face, a heart-shaped pattern on their head and a pattern of spots and bars along their back!"

Is it a slow worm?

Sometimes other reptiles can be seen sneaking around the garden and are mistaken for snakes.

The most common reptile mistaken for a snake is the slow-worm.

The RSPCA says: "Slow-worms (Anguis fragilis) are actually legless lizards and not snakes!

"They can reach around 45cm and unlike snakes, they have eyelids.

"They are typically shades of grey or brown, and some males have blue spots."

What to do if you find a snake in your garden

If you stumble across a native British snake in your garden or in the wild, the RSPCA says to "please leave them undisturbed".

The animal charity said not to contact them unless the snake appears to be injured or wounded.

However, the RSPCA added: "If you find a non-native species of snake, please keep your distance and call our advice line on 0300 1234 999."