The rumour parakeets arrived in the UK when rock star Jimi Hendrix released a pair in London's Carnaby Street in the swinging 60s has finally been scotched.
They also did not escape across the country during the wrap party for the movie The African Queen, in 1951.
In fact, reported sightings from the 1860s have been uncovered, Goldsmiths, UCL and Queen Mary universities say.
Intentional releases may have also been encouraged in 1929-1931 and 1952 when fatal "parrot fever" hit the headlines.
The bright green non-native ring-necked parakeets now thrive across the UK.
Originally from Africa, it has become a successful invasive species in 34 countries on five continents, the study's lead author, the late Steven Le Comber, says.
As well as the rumour from the Bogart and Hepburn classic, in 1951, another suggests that a flock kept at Syon Park escaped when a plane crashed through the aviary roof, in the 1970s.
However, the researchers found their spread across the UK is more mundanely down to repeated intentional releases and not to do with publicity stunts.
Numerous sensational accounts of human deaths due to psittacosis infections from birds were published in 1929.
And in 1932, the Middlesex County Times reported parakeets had been spotted in Epping Forest, with the paper blaming the "parrot disease scare" of 1931 for the observations in the wild.
"Scary" health stories often prompt a strong public reaction, said Sarah Elizabeth Cox, postgraduate history student at Goldsmiths.
"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," she said.
This latest study used geographic profiling, a statistical technique originally developed in criminology to prioritise large lists of suspects in cases of serial crime, to analyse spatial patterns of parakeet sightings.
When applied to biological data, the model can identify the origin sites of diseases or introduction sites of invasive, non-native species.
None of the "suspect sites" connected to origin myths showed up prominently in the geoprofile of more than 5,000 unique records dating from 1968 - 2018.
By 1961, birds were more popular pets than cats and dogs in the UK, with 11 million birds in captivity, of various species, and it seems obvious there would be an increase in escapes, researchers said.