Rat-eating snakes not seen in wild for thousands of years rediscovered in Colwyn Bay

Close up of the Aesculapian snake Credit: Nathan Rusli

Rat-eating snakes that haven’t been seen in the UK wild for thousands of years have been rediscovered breeding in north Wales.

Aesculapian snakes - which can grow to around 1.4m long - have a rich history in Europe and currently the only fossil record from the UK is from the previous interglacial of over 150,000 years or older.

The snakes have been rediscovered in Colwyn Bay, in a population described as localised, which inhabits only a couple of square kilometres around the Welsh Mountain Zoo.

PHD student researcher at Bangor University, Tom Major Credit: Nathan Rusli

It's believed the snakes escaped the zoo and have been breeding ever since.

Discussing the reptiles re-discovery, PHD student researcher at Bangor University, Tom Major told ITV Wales: "In the 1970s, the director of the Welsh Mountain Zoo, Nick Jackson, saw a baby snake crossing the path.

"He checked his field guide and recognised that he was looking at an aesculapian snake. That was the first evidence they were there, and they were already breeding."

An aesculapian snake. Credit: Antonio Gandini

Thanks to the ongoing mark-recapture study, experts now know there are approximately 70 adult aesculapians in Wales.

The researchers search for snakes during standardised snake surveys, and count and mark any individuals found. Using the ratio of marked to unmarked individuals they then use this data to work out how many snakes there are in the population. 

Tom described how large the snakes can become: "Males are larger than females, they get to 1.4 m long. Females reach around 1.2m.

"They feed primarily on small mammals like wood mice and bank voles, occasionally taking nestling birds in the Spring."

The snakes researcher told ITV Wales that his interest in snakes began when he was five years old.

"My grandparents took me to a garden centre where they also had reptiles for sale.

"One of the employees put a corn snake around my neck - I thought it was fascinating, it really blew me away, and I have been hooked ever since."

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You need not worry about your daily walks and runs as the long lost reptiles are completely harmless to humans.

Tom, who hosts a science podcast about snakes called Herpetological Highlights, told ITV Wales: "They are harmless to people and pets. They are non-venomous and kill their small prey by constriction, which interrupts blood supply to the brain."