By: Pete Thomas,

Do you know what a murmuration is, and have you ever witnessed such a dazzling display of avian behavior? The accompanying video shows an enormous flock of European starlings — a murmuration — swirling through the sky in a magnificent ballet that almost seems choreographed. The short-lived seasonal phenomenon, signaling the onset of winter, was captured by Sophie Windsor Clive and Liberty Smith on a canoe trip atop Ireland’s River Shannon. The two-minute clip was posted to Vimeo last week and titled, “A chance encounter and shared moment with one of nature’s greatest and most fleeting phenomena.” This week it began circulating on the Internet, to popular acclaim (stick with it; the show begins after about 20 seconds and improves as the clip progresses).

As for murmurations, they typically occur in late autumn, as the starlings return to roosts after long-distance foraging expeditions. The dusk flights can involve tens of thousands of birds and what’s mystifying is how they can swirl about so swiftly and in such unison without colliding into one another. (Possessing a reaction time of under 100 milliseconds helps.)

Some experts believe the starlings flock together and fly in this manner as a means of defense against predators, such as peregrine falcons. Whatever the reason, a murmuration is a sight to behold. Check out the video and see for yourself.