Sunday, 16 November 2008


All of the frantic activity in the garden that was a feature of the spring and summer has now subsided and the birds are making less frequent appearances. The main visitors at the moment are the sparrows that gather gregariously in the branches of the trees and wait for the food to be taken to the bird table, which they transform instantly into a hub of busy feeding commotion. Blackbirds pass by early in the morning and the tits and the finches pop by any time of day. I am not spending nearly so much on birdseed and even the fat balls last for days. A few Wood Pigeons stop by to clear up after the sparrows and there are still a good number of starlings but not nearly so many now that the fledglings have assumed their winter plumage and are fending for themselves somewhere else.

Starlings are not everyone’s favourites but I miss them. They are gregarious birds, and while in the summer they live in small loose groups, during the winter months they join thousands of others into communal nighttime roosts, which can number several thousand birds, and then spend the day feeding in smaller flocks. The sudden disappearance of the starlings in the winter is caused by summer roosting sites becoming unavailable which forces them to relocate, resulting in the temporary abandonment of some feeding areas.

In the wintertime, both resident and immigrant birds form large roosts, gathering in buildings, trees or reed beds. The roosts often number several thousand, but those that gather in reed beds, for example in Norfolk, can number over a million birds. As the day draws to a close, the Starlings return to the roost and before settling down for the night the increasingly large flock darkens the skies as it swirls around making patterns in the sky. Although not in these great numbers I have seen several large flocks close to where I live and a starling flock like this is called a murmuration, a word that perfectly describes the rustle of thousands of pairs of wings. Starling murmurations are one of the most dazzling displays in the natural world, as a flock continually changes shape like a monchrome kaleidoscope. It seems that my Starlings have just flocked off!
The movement of the flock is a brilliant piece of choreography and ornithologists have discovered that to be a member of a flock individual birds have to learn three simple rules: Steer to avoid crowding local flockmates (separation), steer towards the average heading of local flockmates (alignment) and steer to move toward the average position of local flockmates (cohesion). This is called the flocking algorithm and was first worked out in 1986 and subsequently became important in the world of computer graphics and is used extensively in both developing games and making movies.These huge winter gatherings are boosted by thousands of birds that come to Britain's milder Atlantic climate to escape the harsh cold of the European continent, especially from Scandinavia and Russia. There are several reasons to get together in the way they do, safety in numbers of course, information exchange (if some come back from a good feeding area others may learn of it) and warmth at night through roosting closely together. The birds feed up to twenty miles away from their winter roost but return each evening for company.

Although the Sparrow and the Starling are on the conservation red list in this country it is interesting that by comparison they are doing rather well in the United States. The European Starling was introduced into North America in the 1890s, and quickly spread across the continent. It is a fierce competitor for nest cavities, and frequently expels native bird species and is therefore widely regarded as a pest and has been blamed for a decline in indigenous bird populations, especially the infinitely more attractive Bluebird. The Sparrow and the Starling together with the Pigeon are the only three unprotected bird species in North America, they are all introduced and there are more of them than all the other birds put together.

The European Starling is resident in the US because in 1890, a wealthy American businessman, Eugene Schieffelin, introduced sixty Starlings into New York Central Park and then another forty the following year. In doing so he radically and irreversibly altered America’s bird population because today European Starlings range from Alaska to Florida and even into Mexico, and their population is estimated at over two hundred million.

Schieffelin was an interesting man who belonged to the Acclimation Society of North America, a group with the seemingly laudable, if misguided, aim of aiding the exchange of plants and animals from one part of the world to another. In the nineteenth century, such societies were fashionable and were supported by the scientific knowledge and beliefs of an era that had no way of understanding the effect that non-native species could have on the local ecosystem.

Actually some recent revisionist thinking has concluded that the introduction of the Starling was perhaps not as devastating has had previously been suggested and one thing is certain and that is that is was not nearly so thoughtless as the introduction of the European rabbit to the continent of Australia in 1859 by a certain Thomas Austin who wanted them for his hunting hobby. The effect of rabbits on the ecology of Australia has been truly devastating and entirely due to the rabbit one eighth of all mammalian species in Australia are now extinct and the loss of plant species is at present uncalculated. They have established themselves as Australia's biggest pest and annually cause millions of dollars of damage to agriculture. The introduction of the rabbit was an ecological mistake on a monumental scale!

When he wasn't tinkering with the environment Eugene Schieffelin liked joining clubs and societies and his obituary in the New York Times in 1906 listed his membership of The New York Genealogical and Biographic Society, The New York Zoological Society, The Society of Colonial Wars, The St. Nicholas Club, the St. Nicholas Society and the Union Club of New York which in the 1870’s was generally regarded as the richest club in the world. Obviously Schieffelin had too much money and too much time on his hands!

An alternative theory behind the introduction of the European Starling is often quoted but is probably not true. It is said that he belonged to a group dedicated to introducing into America all the birds mentioned in Shakespeare's works because they imagined the sound of Shakespeare's birds warbling their old world songs on the tree branches of America. If this were true he must have been unusually familiar with the works of the Elizabethan bard because Shakespeare’s sole reference to the starling appears in King Henry IV, part 1 (Act 1, scene 3): “Nay, I’ll have a starling shall be taught to speak nothing but ‘Mortimer.’”

As well as the Starling Schieffelin was also responsible for introducing the House Sparrow, which was released into Brooklyn in New York, in 1851 and by 1900 had spread as far as the Rocky Mountains and is today common across the entire continent. The sparrow too is regarded as a pest as it is in Australia where it was introduced at roughly the same time, paradoxically as an experiment in pest control. How badly wrong can an experiment go I wonder?

Schieffelin wasn’t always successful however and his attempts to introduce bullfinches, chaffinches, nightingales, and skylarks were not successful.

Interestingly the House Sparrow gets four mentions in Shakespeare’s works, in Hamlet, As You Like It, The Tempest and Troilus and Cressida. The full list of avian references in the works of Shakespeare were researched by the Scottish geologist Sir Archibald Geikie and recorded in his book published in 1916, ‘The Birds of Shakespeare’ and they are the Blackbird, Bunting, Buzzard, Chough, Cock, Cormorant, Crow, Cuckoo, Dive-dapper, Dove and Pigeon, Duck, Eagle, Falcon and Sparrowhawk, Finch, Goose, Hedge Sparrow, House Martin, Jackdaw, Jay, Kite, Lapwing, Lark, Loon, Magpie, Nightingale, Osprey, Ostrich, Owl, Parrot, Partridge, Peacock, Pelican, Pheasant, Quail, Raven, Robin, Snipe, Sparrow, Starling, Swallow, Swan, Thrush, Turkey, Vulture, Wagtail, Woodcock and the Wren.

Some people research some very strange things!

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