Murmurations: the dance of the starlings
PUBLISHED: 12:00 17 November 2016 | UPDATED: 10:14 21 November 2016
As the nights grow longer and days colder there's a sense of mystery in the air. Around sunset on a clear evening a great cloud of birds forms, swirling and swooping in a flying dance. Charlotte Hussey of Herts and Middlesex Wildlife Trust looks at the magic and the science of starling murmurations
Starlings are widespread in the UK - a common garden visitor as well as familiar to farmland, parks and towns. They eat fruit and insects and make untidy nests in holes in trees or buildings, in which the female lays five to seven eggs. Both parents raise the chicks. They spend a lot of their time in large flocks, both roosting and, from around this time of year, performing dramatic sweeping, aerial displays. These so-called murmurations before roosting have always captivated those lucky enough to see the phenomenon - flocks of hundreds or even thousands of birds swirling in unison.
The reason behind murmurations and mass roosting has been widely discussed for a number of years. The common consensus is that there are a number of benefits to these groupings: safety in numbers, warmth and information exchange. Often predators will appear at a murmuration – including sparrowhawks and peregrine falcons – in the hope of a good feed, however the sheer number of starlings (much like a school of fish) makes it difficult for predators to target a single bird. Roosting in large numbers offers warmth and the potential of discovering good feeding areas. Roosts grow as the weeks go on in autumn, with some holding around 100,000 birds at one time.
Imagination & myth
Pareidolia – the imagined perception of a pattern or meaning where it does not exist – is high where murmurations are concerned. People see faces, symbols and animals in the ever-moving crowd of starlings swooping above their heads. In Welsh folklore, a princess who was mistreated by her Irish husband, trained a starling to take a message home to her brother and a great war between Wales and Ireland followed. All but seven of the husband’s followers killed. The starling is associated with warriors due to its aggressive manner with other birds. Other mythology has the starling as a messenger from the spirit world and a sign that change is coming.
Science of murmurations
Starling murmurations have caught the attention of more than just birdwatchers; physicists have taken a real interest in the science of a flock’s display. Often, movement is sparked by a predator and a flock moves in waves in an evasive manner that seems instantaneous. In 2010 Professor Giorgio Parisi of the University of Rome found that the change in the behaviour of one bird affected all other birds in the group, no matter how large the grouping. Parisi found that a single bird’s movement only affected its seven closest neighbours but this knock on effect continued through the flock and explains why murmurations look like an ever-morphing cloud. Parisi said, ‘interacting with six or seven neighbours optimises the balance between group cohesiveness and individual effort.’
Where to see one
Now is the perfect time to spot murmurations. Starlings start to congregate at roost sites from mid-October to November, remaining throughout the winter until spring. They roost in places sheltered from both predators and the weather, such as woodlands, reedbeds and buildings. They are often spotted by coastal piers too.
Unlike much birdwatching, there are no special instructions needed to spot them, if they are present, you will see them swirling, swopping and dipping above you!
Sadly, starlings are now on the critical list of UK birds most at risk. In recent years their numbers have fallen by more than 80 per cent; a decline thought to relate to food and nesting shortages, loss of pasture and increased use of farm chemicals. Herts and Middlesex Wildlife Trust is working with farmers and land owners to try and address this sharp drop.
Springwell Reed Bed in the Colne Valley, adjacent to the Herts and Middlesex Wildlife Trust Stocker’s Lake Nature Reserve at Rickmansworth Aquadrome, is a good place to spot starling murmurations. Find more about the reserve at hertswildlifetrust.org.uk.