![]() It might also reduce the chance an individual bird would be eaten overnight by a predator such as an owl or marten. One theory is that spending the night together keeps the starlings warmer as they share their body heat. Scientists think a murmuration is a visual invitation to attract other starlings to join a group night roost. Unlike the V formations of migrating geese, murmurations provide no aerodynamic advantage. After maybe 45 minutes of this spectacular aerial display, the birds all at once drop down into their roost for the night. Murmurations form about an hour before sunset in fall, winter and early spring, when the birds are near where they’ll sleep. ‘Flight of the Starlings’ by Jan van IJken was shot in the Netherlands the audio lets you hear how a murmuration gets its name. This special kind of flock is named for the sound of a low murmur it makes from thousands of wingbeats and soft flight calls. The European or common starling, like many birds, forms groups called flocks when foraging for food or migrating. A murmuration can move fast – starlings fly up to 50 miles per hour (80 kilometers per hour). They look like swirling blobs, making teardrops, figure eights, columns and other shapes. Murmurations constantly change direction, flying up a few hundred meters, then zooming down to almost crash to the ground. The flock splits apart and fuses together again. As many as 750,000 birds join together in flight. If you have a question you’d like an expert to answer, send it to do flocks of birds swoop and swirl together in the sky? – Artie W., age 9, Astoria, New YorkĪ shape-shifting flock of thousands of starlings, called a murmuration, is amazing to see. In North America, wood warblers travel in mixed flocks more than any other family of North American birds.Curious Kids is a series for children of all ages. While many bird species that do form flocks will do so with their own kind, there are also those birds who will fly with other species, again employing the safety in numbers method. This bird migration forecast mapping tool aims to provide real-time predictions of when, where, and how far birds migrate. That discovery eventually led, after many decades of finessing software and collating data, into BirdCast, a remarkable project set up by The Cornell Lab of Ornithology. Some readouts were showing large masses that couldn’t possibly be aeroplanes, and someone correctly guessed it must be birds. The practice of tracking bird flocks by radar first came about as an accident during World War 2, which in itself was a twist on using weather tracking systems to detect enemy planes. Sandhill cranes are those types of birds that like to hang out in pairs or family groups much of the time, but during migration, these birds famously form large flocks between 400,000 and 600,000. This is called unihemispheric slow-wave sleep and it enables the bird to get some rest, whilst the other half of the brain is alert and the other eye is open, on guard.Ĭourtesy of Steve Garvie, Wikimedia Commons. The birds on the edge will be “half-asleep” that is, the side of their head that is inward facing will have a closed eye, and even that side of the brain will have slowed down functions. Computer mapping finally solved the mechanisms behind murmurations. ![]() ![]() You can observe this quite readily among any group of ducks at the water’s edge, where they appear to have arranged themselves in a tight circular group. One of the main advantages of flocking behaviour is to keep a lookout for predators. ![]() It is a remarkable display of working together for a common goal. Over time, the leader will tire, and the birds shift position, giving them a break. Likewise, the two birds behind them benefit from their wingbeats, and so on. The “leader”, usually the fittest bird in that family or species group, will be the head of the V, and the downdraft that their wings create provides uplift for the two birds behind it, positioned on either side at just the right spacing to take advantage of this turbulent air. ![]()
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