Originally from Africa and southern Asia and kept as caged birds, some Rose-ringed Parakeets (aka Ring-necked Parakeets) escaped and by the 1970s started breeding in south-eastern England. One unlikely story says that a small number escaped from Isleworth Studios in 1951 during the making of ‘The African Queen’, another that Jimi Hendrix released them to ‘bring some psychedelic colour to London’s skyline – The total UK population is estimated at 30,000 birds. The largest roost is at Esher, Surrey which holds up to 7000 birds. My local roost at Hither Green is estimated at 3000 birds.
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Having read about these in the news over the last couple of years, I’m still keeping a keen eye out for them! Amazing. Hopefully the warmer weather now will be useful to their survival?
If they move into your area you will hear them as well as see them as they are sometimes incredibly noisy. I think it may be that aspect which a lot of people dislike.