Bird Migration: Physiology and Ecophysiology
Eberhard Gwinner
des. 2012 · Springer Science & Business Media
Rafbók
435
Síður
reportEinkunnir og umsagnir eru ekki staðfestar Nánar
Um þessa rafbók
E. GWINNER! The phenomenon of bird migration with its large scale dimensions has attracted the attention of naturalists for centuries. Worldwide billions of birds leave their breeding grounds every autumn to migrate to areas with seasonally more favor able conditions. Many of these migrants travel only over a few hundred kilo meters but others cover distances equivalent to the circumference of the earth. Among these long-distance migrants are several billion birds that invade Africa every autumn from their West and Central Palaearctic breeding areas. In the Americas and in Asia the scope of bird migration is of a similar magnitude. Just as impressive as the numbers of birds are their achievements. They have to cope with the enormous energetic costs of long-distance flying. particularly while crossing oceans and deserts that do not allow replenishment of depleted fat reserves. They have to appropriately time the onset and end of migrations. both on a daily and annual basis. And finally. they have to orient their migratory movements in space to reach their species- or population-specific wintering and breeding grounds, irrespective of the variable climatic conditions along their migratory routes.
Gefa þessari rafbók einkunn.
Segðu okkur hvað þér finnst.
Upplýsingar um lestur
Snjallsímar og spjaldtölvur
Settu upp forritið Google Play Books fyrir Android og iPad/iPhone. Það samstillist sjálfkrafa við reikninginn þinn og gerir þér kleift að lesa með eða án nettengingar hvar sem þú ert.
Fartölvur og tölvur
Hægt er að hlusta á hljóðbækur sem keyptar eru í Google Play í vafranum í tölvunni.
Lesbretti og önnur tæki
Til að lesa af lesbrettum eins og Kobo-lesbrettum þarftu að hlaða niður skrá og flytja hana yfir í tækið þitt. Fylgdu nákvæmum leiðbeiningum hjálparmiðstöðvar til að flytja skrár yfir í studd lesbretti.
