A Conversation about … Murmurations

MC Escher Sky and Water

Murmuration and starling by Guy Edwardes and Mark Robinson

By Jean Thomas

As a kid, I used to sit on a hill and watch the dark, swirling shapes made by thousands of birds. They chattered and their wings rustled as they alternately swooped over harvested corn fields and clustered in the adjacent trees. They would suddenly all land on a tree and the sky would be empty. Then a few would lift off again, followed by more and more until they were all involved in the dance, sometimes for as long as forty five minutes. The chatter never stopped and I always wondered about what they were telling each other, and how they choreographed all that creative flying.

It wasn't until many decades later that I learned what all that was about. It happens most often in the spring and fall, and it is mostly composed of starlings. Sometimes I have seen mixed flocks including sparrows and red winged blackbirds, but in small numbers. The ornithologists have a raft of theories about this behavior, called murmuration. Among the theories is that the birds gather in formations to confuse predators, and the birds on the outside somehow sound the alarm and the rest of the flock respond with lightning speed to gather and swoop in sync. Starlings have “lateral eyesight”, which is a feature of prey animals. Their eyes are set on the sides of their heads to “look both ways” for predators. Imagine the benefit of thousands of pairs of eyes watching at once.

It is agreed that the most frequent murmurations are at dusk or in the evening, when the flocks prepare to roost en masse. Observations recorded by the birdwatchers include some amazing facts: signals of danger can flash through a flock at the speed of ninety miles an hour; while each bird is autonomous and can initiate motion at will, each bird flies in a subgroup of seven birds, copying their neighbor's motion; flocks can be as large as hundreds of thousands of individuals.

There are areas in Europe that starlings migrate to in winter. Certain sites in Great Britain are famous for the enormity of the flocks doing their aerial dance. Admirersof the display call different shapes “vacuoles”, “cordons” or “flash expansion” depending on the particular movement.

The starling is an unpopular immigrant in North America. We know exactly when and where they arrived. In 1890 in Central Park, New York City, a bunch of Shakespeare fans had the bright idea of introducing every bird mentioned by the bard in his work. They considered themselves ecologists, and mistakenly figured the new birds would contribute to insect control. While not the only successful implant (house sparrows are also everywhere), the starling is now a common pest, particularly at the bird feeder, shouldering hungry natives aside.

A comparison to fish “schooling” is kind of inevitable. They do in the water what the starlings do in the air. I digress, but I thought you might be interested. The fish experts cite the same reasons as they do for the birds, namely, to confuse predators and enable more successful foraging. For some reason, I believe that the birds act this way for many of the reasons listed above, but I believe they do it for the sheer joy of being alive. To watch some of this behavior, go to You tube and enter the word murmuration. The Dutch artist MC Escher made a famous print called “Sky and Water” comparing the fish and fowl.

If you have comments or suggestions for future columns, contact me at jeanthepipper@duck.com.

Remember to Subscribe!