hello tweets,

more bird news that you might want to read ....

regards,

Deborah Wisti-Peterson email:nyneve at u.washington.edu
Department of Zoology, University of Washington, Seattle, Wash, USA
Visit me on the web: http://students.washington.edu/~nyneve/
<><><>Graduate School: it's not just a job, it's an indenture!<><><>


---------- Forwarded message ----------
Date: Wed, 29 Mar 2000 15:22:36 -0800
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> 3_29_2000
> By PAUL HOFMANN
> =A9 Earth Times News Service
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> ROME--The swallows have punctually returned to Europe from their
> winter quarters in Africa, millions of them. Yet ornithologists
> estimate that their number is close to forty percent lower that it was
> ten years ago. Likewise, in the western hemisphere San Juan
> Capistrano, California, reports that fewer of its famous swallows seem
> to come back from Latin America than did once. Environmental changes
> are blamed.
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> Everywhere in the North, the elegant, vivacious birds have for
> thousands of years been welcome as harbingers of the warm season. One
> swallow doesn't make a summer, Aristotle wrote; flocks of them do. The
> Greek philosopher was fascinated by the feathered periodic guests and
> their wanderlust. He speculated that they immersed themselves in some
> swamp in winter to come back to Greece in spring. It turns out that
> Europe's swallows in fact love the marshlands of the Niger delta.
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> Today we know much more about the journeys of the swallows and other
> migratory birds. Such information comes essentially from the small
> identification rings that thousands of bird-friendly volunteers in
> many parts of the world put painlessly on the leg of a captured
> animal, which is quickly released afterward. When it is recaptured or
> found dead in some other place later the data are read, computerized
> and evaluated. A few birds have lately been equipped with tiny radio
> transmitters that allow to monitor their movements in real time.
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> The pioneer of bird-ringing was a Dane, Hans Christian C. Mortensen,
> who in 1899 started systematically tagging storks, starlings and other
> species. The centenary of his project was marked by a birders'
> convention in Denmark last year.
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> The flight plans of the birds are no longer a secret; their
> performances are stunning. Swallows have ben proved to fly for nearly
> 10,000 miles from Central Asia to South Africa, or 5,000 miles from
> Norway to Nigeria. Since they don't like to cross large bodies of
> water, their main flight corridors between Europe and Africa are
> across the Dardanelles and the Near East, between Sicily and Tunisia,
> and across the Strait of Gibraltar.
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> Many questions are nevertheless still unanswered. How do flocks plot
> their routes? On coming back from their winter havens, how do they
> home in on their breeding grounds and often on the nest they built a
> year earlier? Why don't they stay in the subtropical or tropical zones
> rather than venture the exhausting flight back to the cool northern
> climes? How do they know it's traveling time again? Do they have an
> unfailing body clock?
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> Country people know that summer is about to end when swarms of
> swallows assemble on trees and telegraph wires days, even weeks,
> before they will depart. Is there a hierarchy in every flock with some
> senior bird giving the order for takeoff?
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> Swallows, while not domestic animals, have long lived in cohabitation
> with humans and with their livestock. Stables for cattle or horses
> buzzing with flies have since prehistoric times been favorite nesting
> places. But swallows, like storks, favor also house roofs and church
> steeples.
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> The growth of urban districts, probably the air pollution, certainly
> the adoption of industrial methods in farming and animal-breeding and
> spraying of pesticides over vast areas has deprived the swallows of
> many of the insects which they devour on the wing. Conversely, the
> diminished number of swallows has worsened the warm weather scourge of
> mosquitoes in various regions. The chirpily flitting birds used to be
> nature's way of insect control. We would sorely miss them.
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> Copyright =A9 2000 The Earth Times All rights reserved.
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> References
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> 1. mailto:comments2-3-29 at earthtimes.org
> 2. http://www.earthtimes.org/lowgraphics.htm
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