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Stare Ballet buyer vibrations Norwich City

January 31, 2015 at 09:41 GMT Last Updated

A "disturbance of Murmuration" Stare to the event "must" in a city that bird experts.

Up to 2000 birds flying at sunset in the city on the roof of an office building offers a stay "urban heat bubble", Norfolk Wildlife Trust said.

Located in the Coop helps save energy.

The aerial ballet is "one of the best wildlife sanctuaries in the world," said Norfolk farmer and scientist Chris Skinner.