@Cumberbatched What a lovely bird. I keep cats and fish (lots, 4 aquaria LOL!) but have always wanted birds too and dream of being able to let them fly and have them return home.
I'm not sure how realistic this is but its OK to dream as I do not have time while working full-time. I was very busy when I had Guinea Pigs too, I felt like I was running a zoo!
Unfortunately, our government has an eradication programme to prevent this bird establishing in England. I believe farmers are nervous of it feeding on their crops and the nests cause some problems. I'm not sure of the current status of the wild population but £250,000 has been spent on eradication through various methods including shooting in the last decade.
Rose-ringed Parakeet (Psittacula krameri), or as we call it here, Ring-necked Parakeet, do seem permanently established here and are being monitored to establish any harmful effects they have. I believe there are 10,000 birds in the population which is largely confined to the South East of England including London although birds have been reported from all areas.