It's that time of year when you might glance up on your evening commute to see a swirling mass of starlings soaring through the air.

Starling murmurations are a natural phenomenon still only partially understood by zoologists and have intrigued us for centuries.

Even in Roman times, they fascinated Pliny the Elder, who wrote: "It is a thing unique to starlings to fly in troops and to be turned round in a circle just like a ball."