蜜芽传媒

Many of us will have seen murmurations of starlings - huge, pulsating flocks of the birds in the twilight sky.

It's a spectacular sight but it can have messy consequences for people living underneath, as residents of Great Gonerby near Grantham have recently discovered, with lots of people complaining about the birds' droppings covering their homes and cars.

But why do starlings gather in such great numbers, what makes them fly in that manner and how do they co-ordinate it all? Natural history presenter Mike Dilger explains.