The first physiological cue for migration is the improvements within the day size. These alterations are linked to hormonal changes within the birds. Within the time period in advance of migration, quite a few birds Screen higher action or Zugunruhe (German: migratory restlessness), initially explained by Johann Friedrich Naumann in https://cristianltyad.idblogmaker.com/36707704/considerations-to-know-about-budgie-tips-for-beginners-uae