Birds play a significant role in the series. In chronological order:

• a bird hits the window in the flashforward of Al Gough and Fiona Banks ("No More Good Days")
• "Hawk", Janis Hawk's last name ("No More Good Days")
• Pigeon ("White to Play")
• Crows ("137 Sekunden")
• Rudolf Geyer ("Geier" is German for "vulture") ("137 Sekunden")
• Black swan ("Black Swan")
• Bird's Plus ("Playing Cards with Coyote")
• Cockatiel ("Playing Cards with Coyote")
• Marshall Vogel ("Vogel" is German for "bird") ("A561984")
• Raven River experiments ("The Garden of Forking Paths")