Forget tranquilizer darts - that's the stuff of Hollywood. Real police officers use taser, even on a wayward emu:
Authorities in Mississippi said they had to handcuff an emu and shock it with a Taser to remove the ostrich-like flightless bird from a roadway.
Oh, and they used handcuffs, too. I'm assuming they meant emu legcuffs: Link (Sadly, no photo of the cuffed emu)