Dog walkers have been asked to be “extra vigilant” after an adder was seen slithering in the fields on the out-skirts of Dover.

The snake, thought to be more than 2ft long, was spotted in Farthingloe at 1pm on Monday by Steve Oxenham, of West Hougham, who was walking his dog on the grassland.

He saw it just in the nick of time and was able to put Boxer dog Layla on a lead before she had the chance to investigate.

Mr Oxenham said: “I spotted it in one of those double take moments and reacted before the dog could move.

“I put her back on her lead and headed off in the opposite direction. I understand that adder bites on dogs are normally fatal.”

'I understand that adder bites on dogs are normally fatal.' - Mr Oxenham

Mr Oxenham said this is the first time he has seen one in the area, and walks his dog there everyday.

The 61-year-old said he got within 4ft of it and it didn’t react and barely moved within an hour.

He said that its distinct markings enabled him to work out that it was an adder and not a mere grass snake.

After posting a picture of it to Facebook, people from the community commented saying this sighting was nothing out of the ordinary.

“It’s highly unlikely that anyone would own one - apparently they’re seen on the hills around Dover quite often,” Mr Oxenham said.

“I only put it on a Dover Facebook page to draw people’s attention to the fact that they should be alert and vigilant with children, dogs and themselves of course.

According to the BBC’s Nature Features, the adder is “widely distributed” across mainland Britain.

It says that adders are of stockier builds.

They can be seen in moorland, meadows and open woodland.

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