The main physiological cue for migration is the improvements while in the working day duration. These variations are associated with hormonal improvements in the birds. During the period of time prior to migration, many birds Display screen increased activity or Zugunruhe (German: migratory restlessness), to start with described by Johann https://cat-health-tips-dubai65329.blog2learn.com/85238832/5-simple-statements-about-pet-bird-explained