are there any scientists who observed or studied this phenomenon?
Yes, Johannes Leche.
Bird migration
Early studies on the timing of migration began in 1749 in Finland, with Johannes Leche of Turku collecting the dates of arrivals of spring migrants.
where do birds go when they fly south The southern oceans. what is this phenomenon called? It is the regular seasonal movement, often north and south along a flyway, between breeding and wintering grounds. do changes in climate affect this migration? Yes, large scale climatic changes are expected to have an effect on the timing of migration.
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Bird migration [SEP] Study techniques
Early studies on the timing of migration began in 1749 in Finland, with Johannes Leche of Turku collecting the dates of arrivals of spring migrants. Bird migration routes have been studied by a variety of techniques including the oldest, marking. Swans have been marked with a nick on the beak since about 1560 in England. Scientific ringing was pioneered by Hans Christian Cornelius Mortensen in 1899. Other techniques include radar and satellite tracking. The rate of bird migration over the Alps (up to a height of 150 m) was found to be highly comparable between fixed-beam radar measurements and visual bird counts, highlighting the potential use of this technique as an objective way of quantifying bird migration.