No one knows why they do it. Yet each fall, thousands of starlings dance in the twilight above England and Scotland. The birds gather in shape-shifting flocks called murmurations, having migrated in the millions from Russia and Scandinavia to escape winter’s frigid bite. Scientists aren’t sure how they do it, either. The starlings' murmurations are manifestations of swarm intelligence, which in different contexts is practiced by schools of fish, swarms of bees and colonies of ants. As far as I am aware, even complex algorithmic models haven’t yet explained the starlings’ aerobatics, which rely on the tiny birds' quicksilver reaction time of under 100 milliseconds to avoid aerial collisions—and predators—in the giant flock.
Despite their tour de force in the dusky sky, starlings have declined significantly in the UK in recent years, perhaps because of a decline in suitable nesting sites. The birds still roost in several of Britain’s rural pastures, however, settling down to sleep (and chatter) after their evening ballet.
Two young ladies were out for a late afternoon canoe ride and fortunately one of them remembered to bring her video camera. What they saw was a wonderful murmuration display, caught in the short video - URL is below. Watch the variation of color and intensity of the patterns that the birds make in proximity to one other. And take a look at the girl in the bow of the canoe watching the aerial display.