The Leader | Evening Standard daily

Mudlarking is the historic pursuit of combing the Thames foreshore for, hopefully, some rare or valuable artefacts to give us a glimpse back into history of how Londoners used to live.

Among the coins, bottles, occasional weapons and oddities like tiny Roman spoons for scooping out ear wax found nestling in the silt, mudlark Jason Sandy made a chilling discovery - what was apparently a giant boa constrictor skin that had been shed by its occupant.

So, does this clue reveal a big snake on the loose near to Chiswick? Hopefully not, but it could join legions of exotic animals now wandering, slithering and swinging around the capital, which include terrapins, parakeets and even sightings of what’s claimed to be a puma roaming south-east London.

Many of the exotic non-native species found around London are believed to have been thrown out after their owners could not cope with responsibility, such as the terrapins flushed away after the 90s Teenage Mutant Ninja Turtles craze. 

Last year, a project began in Black Park lake in Wexham in Buckinghamshire to relocate non-native terrapins over their threat to wildlife.

So, what happens when these animals disappear into the London ecosystem?

To discover what’s lurking in the capital’s waterways and undergrowth, we’re joined by Dr Mark Jones.

We discuss how shocking numbers of exotic pets in the UK now include monkeys and the legislation needed to crack down on the illegal wildlife trade.