Murmuration of Starling (part 1)

Yesterday I told you I was go into show you something that I have always wanted to see.  Well on 7 November this year I was not only able to achieve that but videoed it and today I will show you.  On a cold windy but clear skied evening at dusk, I waited for the

 

Murmuration of Starlings

to arrive over the Albert Bridge in Belfast.  So really the post is mainly the video at the end of the first birds gathering and watching the rest join in the group until there were tens of thousands doing their aerobatic manoeuvres in the night sky.

 

 

Starling

 

Would you pull over your car just to watch some starlings? A gathering of only a few of these speckled, iridescent-black birds isn’t a very alluring sight—particularly in North America, where these birds are invaders. The European Starling was originally introduced here by a group of well-meaning Shakespeare enthusiasts in 1880, but many Americans now consider them to be pests that serve little purpose other than to dirty car windshields and destroy crops. 

 

 

Scientists have been studying this phenomenon for years, watching the dazzling cloud, swirling, pulsating, drawing together to the thinnest of waists, then wildly twisting in pulses of enlargement and diminution.   It’s certainly is worth stopping your car for, and even though my still camera has no big lens, the light conditions were bad, and I shot the whole thing through my view finder when mostly I could not see the birds at all, still I hope you would find the video interesting.

 

 

So how do these masses of birds move so synchronously, swiftly, and gracefully? This isn’t an idle question—it has attracted the attention of physicists interested in how group behaviour can spontaneously arise from many individuals at once.  In 2010, Andrea Cavagna and colleagues at the National Council of Research and the University of Rome used advanced computational modelling and video analysis to study this question. They found that starling flocks model a complex physical phenomenon, seldom observed in physical and biological systems, known as scale-free correlation.

Surprising as it may be, flocks of birds are never led by a single individual.  Even in the case of flocks of geese, which appear to have a leader, the movement of the flock is actually governed collectively by all of the flock members.  But the remarkable thing about starling flocks is their fluidity of motion.  As the researchers put it, “the group respond[s] as one” and “cannot be divided into independent subparts.”

 

When one starling changes direction or speed, each of the other birds in the flock responds to the change, and they do so nearly simultaneously regardless of the size of the flock. In essence, information moves across the flock very quickly and with nearly no degradation. The researchers describe it as a high signal-to-noise ratio.

This scale-free correlation allows starlings to greatly enhance what the researchers call “effective perceptive range,” which is another way of saying that a starling on one side of the flock can respond to what others are sensing all the way across the flock—a huge benefit for a starling trying to avoid a falcon.

 

A new study on starling flocks and led by George Young at Princeton, did their own analysis of murmuration images to see how the birds adjust to their flock mates. They determined that starlings in large flocks consistently coordinate their movements with their seven nearest neighbours. They also found that the shape of the flock, rather than the size, has the largest effect on this number; seven seems optimal for the tightly connected flocks that starlings are known for.

Imagine a game of telephone: one person passes a message along to the next person, who repeats it to another, and so on. For humans, the telephone message loses information very quickly—that’s what makes the game fun.

The first finding, by Cavagna’s team, suggests that very little information is lost in a starling flock. The second finding, by Young’s team, suggests that starlings “play telephone” with their seven nearest neighbours. Somehow they are able to process messages from those seven neighbours all at once, and this is a part of their method for achieving scale-free correlation.

Still, neither finding explains how starlings are capable of such extraordinary collective responses.

As the researchers admit, “How starlings achieve such a strong correlation remains a mystery to us.”

The video can be accessed at

http://youtu.be/J_H05UBqIwg

Now it is certainly a time for a cuppa and to sit back and enjoy this wonderful spectcale of nature.

Roger on a comment on google + suggested I take the background sound out and add music which I have now done so thanks Roger for that sugggestion as the video is much better.  Click off the Ad at the beginning.

If there is a black space below, click it and the video will appear.

I know the video was a bit long however I wanted you to see it from a couple of hundred birds arriving until the ball of Starling was complete.  It really took about 40 mintues for them all to arrive and join the group. 

When I reallised they had all arrived and were ready to descend to roost under the bridge for the night, I decided to let my video run continuously and it took 4 minutes 50 seconds for them all do that. 

Tomorrow I will show you that video.   I personally found this fascinating and amazing.  I hope I have been able to convey some of the excitement I expereienced on that evening.

Many thanks for visiting and also for leaving comments.  A special thanks for those bloggers who suggested what the sheep were saying.  I did indeed get a great laugh from that. I nearly choked laughing when I read Roy's reply but oh so true!