Have you looked outside your window and been surprised to see a flock of green birds perched on your garden fence?

Well you’re not the only one.

Bemused residents have been reporting sightings of hundreds of green parakeets flying above their homes – many of whom have made themselves at home in gardens across the borough nibbling at bird feeders.

People who have posted comments on the social forum site Streetlife, have described these feathered fowls as “pretty” but “noisy” and some suggest the influx might be due to the birds rapidly multiplying.

David Cook, of Corbets Tey, Upminster, said: “I’m a surveyor and spend much time at other people’s homes so I get to see a variety of garden wildlife.

“I first saw the green parakeets a couple of years ago but I’ve since spotted them in Gidea Park, Harold Wood and other parts of Upminster as well as Woodford Green and North Stifford.

“I think there’s a local flock of about 15 that hang around Parklands open space.”

These mysterious birds are ring-necked parakeets.

In the 1960s a few birds settled down in Havering but hundreds more have made their homes in the borough in the past few weeks.

Howard Vaughan, information officer at RSPB Rainham Marshes, said: “Many of them used to roost in Lewisham and Kent and fly across the marshes but these are clever birds and knew it would be a lot easier for them to just stay here.

“The best advice we can give is to just leave them to it as they’re not harmful creatures.

“And if you like them hanging around, then get yourself a bird feeder and leave out things such as nuts and sliced up apples for them to get their beaks into!”