(Okay, the one I saw was tiny compared to that one, but you get the picture.)
The first time I remember seeing a murmuration was in 1994 in Aberdeen, and I was sitting in the Pizza Hut on Union Bridge and it was approaching dusk and I looked out and saw a moving cloud of birds; not a mere "flock" of them, but a visual symphony of black points moving like a sinuous blanket across the sky and dipping down toward the buildings before sharply rising again to the deep red evening sky. As I sat mesmerized, I slowly finished the stuffed crust pizza that I ordered. And I wasn't the only one that stopped to watch the spectacle, either.
But why is it called a "murmuration" anyway? There is no sufficient etymology over at dictionary.com's definition. Off to my favorite English language site: World Wide Words.
And here's the explanation:
People often write in about the conventional terms for groups of animals and people, especially birds, such as parliament of rooks or murder of crows. Many of these, including ...murmuration of starlings..., are poetic inventions that one can trace back to the fifteenth century.And so there we go: it's a nod to a piece of writing from a 15th century book written by a prioress at St. Alban's to describe - in "a muted way" the chirruping that starlings make when the roost in the evening. (I would have called them a "Chittering of Starlings" but while that might - to me - sound more onomatopoetically correct, it is far less poetic than Dame Juliana Barnes.
The first collection in English is The Book of St Albans of 1486... The part on hunting [with all the names of groups of animals] is inscribed with the name of Dame Juliana Barnes, who is traditionally supposed to have been prioress of the nunnery of Sopwell near St Albans...
Though some of Dame Juliana’s terms ... are wonderful to read and have a certain resonance, nobody seems to have used them in real life (and some are now mysterious, such as cete of badgers or dopping of sheldrake, because we no longer have the vocabulary to appreciate them).
Many that refer to natural history have some basis in animal behaviour. A ... murmuration of starlings is a muted way to describe the chattering of a group of those birds as they come into roost each evening...
Go over to World Wide Words to check out some more poetic (if rather obscure) words to describe groups of animals.