There are many different terms for a flock of birds, but when it comes to starlings, the word we most often use is “murmuration”.
A murmuration specifically refers to the breathtaking sight of thousands, sometimes even hundreds of thousands, of starlings flying together in synchronised, ever-shifting patterns. The term comes from the soft murmuring sound their wings produce as they swoop and twirl across the sky.
For decades, scientists have studied murmurations to understand why starlings behave this way. In the 1930s, British ornithologist and author Edmund Selous even suggested that starlings might possess psychic or telepathic abilities to coordinate their movements.
Today, thanks to advances in technology, researchers use high-speed cameras and digital image processing to track individual starlings within a flock, allowing them to gain deeper insights into the mechanisms behind these mesmerising displays.
In 1987, computer scientist Craig Reynolds developed a simulation of flocking behaviour called Boids. In this model, virtual birds followed just three simple rules:
Separation – nearby birds moved further apart to avoid crowding.
Cohesion – distant birds moved closer together to maintain group unity.
Alignment – birds adjusted their direction and speed to match their neighbours.
Despite the simplicity of these rules, Reynolds found that they could produce remarkably complex flocking behaviour. His model was later used to create computer-generated swarms of bats and armies of penguins in Tim Burton’s Batman Returns.
In 2008, researchers from the Centre for Statistical Mechanics and Complexity in Rome made significant breakthroughs in understanding murmurations. They filmed flocks of up to 4,000 starlings flying over the National Museum from multiple angles and created 3D reconstructions.
Their findings challenged previous theories, which assumed that birds coordinated based on metric distance, interacting with others within a fixed range. Instead, they discovered that murmurations operate on topological distance: each bird interacts with a fixed number of neighbours – typically six or seven – regardless of how far apart they are. This means that whether the flock is dense or sparse, each bird still communicates with the same number of neighbours.
The team also observed that starlings maintain closer distances to birds beside them than to those in front or behind, likely to prevent collisions during intricate manoeuvres.
In 2013 a further study led by George Young from Princeton, an Ivy League research university in New Jersey, found that starlings in large murmurations consistently coordinate their movements with their seven closest neighbours. The researchers also found that starlings can simultaneously process information from those seven neighbours which is how they achieve something called scale-free correlation.
Unlike geese flying in a V-formation, where a leader guides the flock, murmurations exhibit no central control. Instead, this scale-free correlation allows thousands of starlings to change direction simultaneously, without any single bird leading the movement.
Although the precise mechanism behind this remains unclear, researchers suggest it may be similar to phase transitions phenomena explained by physics rather than biology. These include the transition of water into steam, the formation of crystals, or avalanches, and other transitions between solids, liquids, and gases, and sometimes plasma
A murmuration behaves as a critical system, finely balanced to respond instantly to environmental changes. When a predator, such as a bird of prey, disturbs part of the flock, the reactions of the closest birds ripple through the group like a wave, resulting in changes of direction and producing the stunning aerial patterns we see. Remarkably, little information is lost in this process, a phenomenon particle physicists refer to as a low-noise system. However, how starlings achieve such precise synchronisation at high speeds remains a mystery.
Another discovery, aided by computer simulations, is that birds in a murmuration actually fly at a steady speed. Although it appears as if they slow down and speed up, compressing into denser formations before drifting apart, this is an optical illusion caused by our 2D perspective of a 3D phenomenon.
Scientists have proposed several theories to explain why starlings form murmurations. One widely accepted explanation is protection from predators. A swirling mass of thousands of birds makes it incredibly difficult for a predator to single out and catch an individual bird.
Another possible reason is temperature regulation. On cold nights, the collective body heat of a murmuration can raise the surrounding air temperature by a few degrees, helping the birds stay warm as they prepare to roost. Murmurations may also serve as a way for starlings to exchange information, such as the best feeding or roosting locations.
Aerodynamic efficiency is another factor that may contribute to this behaviour. Similar to how geese benefit from flying in a V-formation, starlings in the centre of a murmuration likely experience reduced wind resistance, allowing them to conserve energy during flight.
Murmurations could also play a role in social bonding and communication. As highly social birds, starlings may use these coordinated displays to reinforce group cohesion and maintain connections within large populations. For younger or less experienced birds, murmurations may serve as practice for flight coordination, helping them develop agility and improve their response times in complex aerial manoeuvres.
Beyond simple predator avoidance, murmurations may act as an advanced evasion strategy. The constant shifting of the flock’s shape and density can actively disorient predators such as peregrine falcons, making it much harder for them to track and strike a target.
Some researchers also suggest that murmurations are influenced by environmental cues, including changes in air currents, light levels, or even electromagnetic fields. These external factors might prompt the flock to move in synchrony as part of a broader survival strategy.
While no single explanation fully accounts for this mesmerising phenomenon, it is likely that murmurations serve multiple functions. They combine predator avoidance, social interaction, energy efficiency, and environmental responsiveness into one of nature’s most spectacular displays of collective behaviour.
The best time to witness murmurations in the UK is between October and March, with the most spectacular displays occurring during the winter months. This is when thousands of starlings migrate from continental Europe to escape harsher weather, swelling the UK’s resident starling population and creating the vast, mesmerising flocks that fill the evening sky.
Murmurations typically take place at dusk, just before the birds settle into their communal roosts for the night. As daylight fades, small groups of starlings begin to arrive, gradually merging into an ever-growing, swirling mass. The movement appears almost choreographed, as the flock shifts and pulses in perfect synchrony.
On dull, overcast days, murmurations may start slightly earlier, as the birds react to lower light levels. Prime locations to observe this breathtaking spectacle include reed beds, woodlands, cliffs, and even urban areas, where starlings often gather in large numbers before descending into their roosts.
One Response
Fascinating. I saw one of these beautiful murmurations over Brighton pier when I was a boy. Something I have never forgotten & would love to see again one day.