Which birds are flightless?
There are 7 families of flightless birds in total. They include the Kiwi, Cassowaries, Rheas, Ostriches, Tinamous, Emus and Penguins.
There are also numerous flightless birds within other groups of birds which are mostly made up of species which can fly. Rails, for example, include waterfowl such as moorhens, swamp hens and other small to medium birds which can fly but prefer not to. They cannot fly for any great distance, and within the rail family, there are numerous flightless birds, such as the Takahē and the weka of New Zealand, and the Inaccessible Island rail.
Other bird families have some members which cannot fly, even though most of the family can. The kakapo, which lives in New Zealand, is the world's only flightless parrot. The flightless steamer duck of the Falkland Islands is another bird which is an anomaly with its family. The Giant Coot of South America is unusual, as the adult cannot fly, but the young birds can.
There are many more species of flightless birds. See the related link for a more complete list.
Extinct birds which could not fly include the Moa, dodo, elephant bird and Terror bird.