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Posts Tagged ‘starlings’

Photo: Daniel Biber, via the Independent
A murmuration of starlings was targeted by a bird of prey and took the form of a giant bird. But contemporary scientists insist “thinking” isn’t involved. 

The natural world never ceases to amaze. Consider the flight of large groups of starlings. You have probably seen some of the YouTube videos. Mark MacNamara wrote about the phenomenon at Nautilus in March.

“Eugene Schieffelin was the eccentric ornithologist who in 1890 shipped 60 starlings from London to New York City and set them free in Central Park. The next year he released 40 more, and today there are maybe 200 million starlings in the United States and Southern Canada. [Starlings] are shrewd flyers, clever mimics, and often unwelcome … displacing woodpeckers and flycatchers, and destroying entire crops of berries and cherries. Not to mention the havoc they cause at many airports.

“Ah, but when they come round in their murmurations on fall afternoons, or in early winter, what magicianry is that, gathering up out of nowhere, arriving in strands or massive clusters, over inlets or forests. You’ll see them fill up neighboring trees and fall into an oily, high-pitched chatter. [The] most subtle spooking will do it, a dog’s bark, the slam of a car door down the street, or nothing at all, and off they go at 50 miles per hour, wheeling around the countryside, sheets and sheets of them, thickening and thinning, blackening and scattering, merging and splitting. …

“The performance is self-organized, cohesive, and perfectly synchronized; and distinguished by elaborate patterns of spirals, spheres, planes, and waves. What causes starlings to perform these displays? …

“Theories have evolved over the last century. In 1931, Edmund Selous, a renowned ornithologist and bird activist [sumised] that birds in a flock must all be ‘thinking’ as one; how else to explain the synchronization except by telepathy. …

“Later theories suggested that murmurations are ways to find food and keep warm. Those theories linger, but in the past 50 years the predominant explanation is predation, particularly the role of raptors, such as hawks and falcons, in triggering escape behaviors that involve particular patterns of grouping. …

“In the mid 1960s, researchers found that murmurating birds, particularly starlings, interact—not always, but often — with six or seven of their closest neighbors, who interact with six or seven of their closest neighbors. In recent years, studies posit that a network with seven neighbors optimizes the trade-off between ‘group cohesion and individual effort.’

One theory among researchers, in the context of predation, is that starlings are ‘managing uncertainty while maintaining consensus.’ …

“In a murmuration, the distance between fellow fliers is based on a set of rules also seen in certain kinds of fish and insects. These rules require birds to draw closer to birds farther away; at the same time, not to get too close to the nearest neighbor; and finally to join in directional flow. Add to these rules the aerodynamic factors in starlings — and the blistering speed at which the birds turn, climb, and dive — and you have a sense of the intricacy of flock synchronization. …

“In 2019, evolutionary biologist Rolf F. Storms at the Groningen Institute for Evolutionary Life Sciences in the Netherlands, led a study on starlings that delved into the rules of murmurations. … The study [found] different patterns of escape by the starlings.

“For example, when a falcon attacked a flock from above — not from the sides or below, and at high speed — the starlings frequently [scatter] in all directions in the sky. … When a falcon attacks starlings at medium speed, allowing it to be detected, warnings spread through the flock, and the birds respond in a ‘wave.’ They turn right and left, zig and zag, creating ‘darkened bands’ that ripple through the flock, confusing the falcon. …

“Grainger Hunt, Senior Scientist Emeritus with the Peregrine Fund’s California Condor and Aplomado Falcon restoration project, underscores the fact that murmurations are emergent. …

” ‘The peregrine does not purpose the shapes and movements of the flock. Nor does any starling. The spectacle of wondrous shapes and movements is an unintended effect. The peregrine is trying to catch a starling, and each starling is trying not to get caught.’ ” More.

Would you agree that humans need to learn from the starlings how to maintain consensus while managing uncertainty? What a concept!

Video: Dylan Winter
A murmuration of starlings.

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Photo: Josh Levinson
The European Starling is thought to adorn its nest with flowers to ward off pests.

One of my favorite shows is Living on Earth, an environmental program recorded in Greater Boston and produced by Public Radio International (PRI). One of the show’s regular features is called BirdNote, and you can learn a lot about individual species just from that.

The Living on Earth website recently posted this:

“STEVE CURWOOD: European Starlings can often be found scrounging through the grass of a backyard or a nearby park for tasty treats. But now and then, they’ll also pluck a marigold or other bright flower to bring back to the nest. These flowers aren’t just for decoration, as Michael Stein explains in this week’s BirdNote. It appears to bring health benefits to their young.

“It’s Living on Earth. I’m Steve Curwood.

“European Starlings famously travel in massive flocks, up to one hundred thousand birds strong at times. They can almost resemble a school of fish moving together in a squeaky symphony. And, BirdNote’s Michael Stein reports that when starlings are paired up and raising chicks they have an unusual way to keep their nest clean and healthy. …

“MICHAEL STEIN: Watch long enough, though, and you may see a starling pause in the hunt to neatly pluck a marigold or other bright flower – and then fly up to deposit the bloom in the nest.

“How romantic. But there’s more to it. Ornithologists have found that starlings regularly adorn their twig nests with fresh vegetation – the more fragrant the better. Marigolds, of course, but also elderberry flowers, yarrow leaves, and even willow bark.

“All of which – as your nose will tell you – are full of aromatic chemicals. The starlings are actually fumigating their nests. Why? The chemicals have been thought to help discourage pests and parasites. Scientists have discovered that the smelly plants may offer an even more direct benefit to nestlings – by stimulating their immune systems.
It turns out that starlings hatched in well-fumigated nests tend to weigh more and live longer than those raised without benefit of fragrant herbs.” More.

For another Living on Earth BirdNote, click here. This one is about a Laysan Albatross called Wisdom who was still producing chicks in 2018, despite the fact her 67 years made her quite old for her species. Who knew the Albatross could live so long?

This might be a good time to remind you how Coleridge used an Albatross in the Rime of the Ancient Mariner to send a message — not just to the stunned and speechless wedding guest but to us all:

Farewell, farewell! but this I tell
To thee, thou Wedding-Guest!
He prayeth well, who loveth well
Both man and bird and beast.

Photo: Kiah Walker, USFWS, CC
Wisdom the Laysan Albatross was still producing chicks at age 67. She doesn’t even look tired.

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Photo: PA/Owen Humphries
Murmuration of starlings over Gretna, Scotland

Starlings swarm in flash mobs over Scotland every November and February, and they don’t even need social media to remind them it’s time.

According to an article at the BBC, “Tens of thousands of the birds are regularly seen around this time of year near the Dumfries and Galloway town. It is one of the most famous locations for the natural spectacle, the reason for which is not definitively known.

“A survey of the birds across the UK is currently under way with members of the public urged to record sightings. The poll, conducted by the University of Gloucestershire and the Society of Biology, is the first of its kind and has already received more than 600 reports from Cornwall to John O’Groats.

“Dr Anne Goodenough, reader in applied ecology at Gloucestershire University, said: ‘One of the theories behind the murmurations is that it means they are safer from predators such as hawks and falcons.

” ‘Another theory could be they are signalling a large roost and it could be a way of attracting other birds to that area to build up a big flock as it would be warmer. It’s much warmer to roost as a big group rather than a smaller one and the murmurations can be as big as 100,000 birds.’ ”

More here. Don’t miss the other amazing photos at the BBC site.

YouTube video: DylanWinter@virgin.net

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