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Bird Migration_Video
Examples
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This page takes a brief look at bird migration, and couples this with the use of basic video. The first two videos use Flash MX, the botton two videos use QuickTime. Of the Flash MX movies, the first one uses buttons to control video playback, a play and a stop button are used in this example, plus a couple of lines of actionscript. The second example uses a video file controller and utilises the Macromedia Library. This gives a controller with stop, start, move to different clips etc. |
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| Many birds populations migrate long distances
along a flyway. The most common pattern involves flying north to breed in
the temperate or Arctic summer and returning to wintering grounds in warmer
regions to the south.
The primary advantage of migration is energetic. The longer days of the northern summer provide greater opportunities for breeding birds to feed their young. The extended daylight hours allow diurnal birds to produce larger clutches than related non-migratory species that remain in the tropics year-round. As the days shorten in autumn, the birds return to warmer regions where the available food supply varies little with the season. These advantages offset the high stress, energetic costs, and other risks of the migration. Predation can be heightened during migration; the Eleonora's Falcon which breeds on Mediterranean islands has a very late breeding season, coordinated with the autumn passage of southbound passerine migrants which it feeds to its young. A similar strategy is adopted by the Greater Noctule bat, which preys on nocturnal passerine migrants.[2][3][4] The higher concentrations of migrating birds at stopover sites also make them prone to parasites and pathogens requiring a heightened immune response.[5] Contact regarding any aspect of embedding video ------pennine@bigstring.com |
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