Dog walkers, tourists and other members of the public have been warned after a six foot boa constrictor was spotted at a popular beauty spot in North Yorkshire.
Ed Ryder spotted the snake while out walking with his girlfriend at Swinsty Reservoir, near Harrogate.
And, just to prove his point, Mr Ryder even managed to get a picture of the reptile's tail as it slithered away (above).
He saw the snake at about 6pm on Saturday, and it is believed to be an abandoned or lost pet.
North Yorkshire Water, which owns the site, has now issued a warning for walkers to be on their guard.
Geoff Lomas, site manager for Yorkshire Water, told the Daily Mail: "Over the years, we've discovered a number of escaped or unwanted exotic pets at our recreational sites across the region, such as terrapins and koi carp, but never an exotic snake more commonly found in the jungles of South America.
"Clearly there is some concern in that we have a snake, of which we know very little, including when it last ate, on the loose in a vast woodland area which is very popular with visitors from across the region.
"Whilst a boa constrictor is unlikely to pose a risk to humans, a lot of people walk their dogs around the site and clearly small dogs could be at a small risk from such a predator.
"With this in mind, we're saying to people, please do come to the site, but please be sensible and exercise caution when out and about, ensuring all dogs are kept on a lead.
"If you do spot the snake, please let us, the police or the RSPCA know as quickly as possible, and every attempt will be made to safely capture the snake and hopefully return it to its owner."
Boa constrictors generally grow up to 12ft, but the largest ever found was 18ft. They are not venomous and swallow their prey whole after squeezing it to death.
As they thrive in high temperatures, experts have said it may be too cold for a boa to survive in Swinsty.
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