Old 24th Nov 2017, 02:58
  #22 (permalink)  
cats_five
 
Join Date: Jan 2008
Location: UK
Posts: 1,348
Originally Posted by etudiant View Post
Surprised that people are unaware that birds migrate mostly at night. They use the day to feed. The nexrad radar in the US gives a ringside seat. One can watch the masses of birds take off at dusk and gradually settle in near dawn. UW-Madison Department of Atmospheric and Oceanic Sciences
Depends what sort of bird & where. Some routes they use thermals to help climb so obviously start during the morning.
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