JIMI Hendrix, George Michael, Humphrey Bogart and Katharine Hepburn all have one thing in common. They can now rest in peace having been cleared of all blame in the mystery of the proliferation of parakeets in the UK.

The squawking, bright green, ring-necked parakeet is a burgeoning presence in our green spaces. Victoria Park in Glasgow is home to around 30 of the creatures. But how the invasive tropical birds got here in the first place has long been a subject of contention.

One urban legend traces their origin to rock icon Hendrix, who released the first pair of parakeets, named Adam and Eve, as a symbol of peace while he was a wee bit high in London’s Carnaby Street back in 1968. Another suggests they arrived in 1951 when Bogart and Hepburn visited London with various exotic animals to film The African Queen, set in the country’s equatorial swamps. There’s also a theory Michael was the culprit, after burglars broke into his Hampstead home in the 1990s and raided his aviary. Apparently he was worried about police getting involved and didn’t report the crime.

The National: The arrival of these birds is shrouded in urban mythThe arrival of these birds is shrouded in urban myth

Now the question has been subjected to a rigorous forensic analysis for the first time, in research that points to an entirely different explanation: pet owners around the country releasing the birds into the wild, prompted by media coverage of fatal “parrot fever” outbreaks.

Research carried out at London’s Queen Mary University based on geographic profiling methods used to track down criminals concluded that the parakeet population has grown from numerous small-scale accidental and intentional pet releases.

The analysis tested other popular theories, including that parakeets kept at Syon Park in west London escaped in the 1970s when a plane crashed through the aviary roof, or that damage to aviaries during the Great Storm of 1987 was responsible. However, none of the suspect sites showed up in the heat map of more than 5000 unique records dating from 1968 to 2018.

The research, published in the Journal Of Zoology, drew on sightings recorded in the National Biodiversity Network Atlas dating back to the 1960s. When this failed to produce an obvious hotspot of activity, the scientists turned to newspaper archives, and a search turned up thousands of pages of news stories about parakeets written between 1804 and 2008.

The team found various sensational accounts of human deaths due to parrot fever, an infection called psittacosis, which can be passed from bird to human and which can be deadly. In 1932 the Middlesex County Times reported that parakeets had been spotted in Epping Forest and credited the “parrot disease scare” of 1931 for an increase in pet birds being released into the wild.

A 1952 headline in London’s Daily Herald reported calls to “stop import of danger parrots”, while a 1974 report in the Reading Evening Post described eight people falling sick after the death of a parrot.

Sarah Elizabeth Cox, a postgraduate history student at Goldsmiths, said: “It is easy to imagine [these] headlines leading to a swift release of pets. If you were told you were at risk being near one, it would be much easier to let it out the window than to destroy it.”

Mystery solved ... just a classic case of bird flew.