In the 2010 film co-produced by M. Night Shyamalan, the flying bison is voiced by which actress? 
Appa (character):  Dee Bradley Baker voices Appa, along with all the other animals, in both the TV series and the film. The Last Airbender: The Last Airbender is a 2010 American action fantasy adventure film written, co-produced, and directed by M. Night Shyamalan.
Dee Bradley Baker