Thousands upon thousands of starlings swirl through the sky on their way home to their roost.

Eastern Daily Press: This amazing photograph of a murmuration of starlings was taken by Andrew Smiley was over Walberswick in December 2013. Now it is one of 36 such Smiley images of massed birds rising on our coast like billowing smoke or falling like shaken blankets companioning a poetic new text by Suffolks Julia Blackburn, musing on the recent death of her sculptor husband. Murmurations of Love, Grief and Starlings is published by Full Circle Editions at £10.This amazing photograph of a murmuration of starlings was taken by Andrew Smiley was over Walberswick in December 2013. Now it is one of 36 such Smiley images of massed birds rising on our coast like billowing smoke or falling like shaken blankets companioning a poetic new text by Suffolks Julia Blackburn, musing on the recent death of her sculptor husband. Murmurations of Love, Grief and Starlings is published by Full Circle Editions at £10. (Image: Archant)

The incredible sight, seen in Norfolk and further afield, is called a murmuration.

Huge flocks begin to form at this time of year, as the birds more to winter roosting sites - often in towns and cities.

Eastern Daily Press: A murmuration of starlings before they set down to roost over the town centre in Great Yarmouth. Picture: James BassA murmuration of starlings before they set down to roost over the town centre in Great Yarmouth. Picture: James Bass

They've been observed in massive numbers in towns from King's Lynn to Great Yarmouth, as well as more rural areas.

According to the RSPB: 'It's basically a mass aerial stunt - thousands of birds all swooping and diving in unison. It's completely breathtaking to witness.

Eastern Daily Press: Starlings in Cromer on Saturday March 21. Picture: Phil BaconStarlings in Cromer on Saturday March 21. Picture: Phil Bacon (Image: Archant)

'We think that starlings do it for many reasons. Grouping together offers safety in numbers – predators such as peregrine falcons find it hard to target one bird in the middle of a hypnotising flock of thousands.

'They also gather to keep warm at night and to exchange information, such as good feeding areas.'

Eastern Daily Press: Murmuration of Starlings over Thurne Mill. Photo challenge: skyline.Murmuration of Starlings over Thurne Mill. Photo challenge: skyline. (Image: (c) copyright newzulu.com)