appearance aquatic bird Australian bird birds circles circular common fauna fowl light movements moving native-fauna omnivore omnivorous peaceful placid pond reflections ripples rippling swamp-hen swimming textures water waterbirds waterfowl wild-life duck ducks big big bird cultural culture curious curly double-feathers dromaius novaehollandiae Emu fast flightless icon iconic large long-legged long-legged flightless bird male native nomadic omnivore plumage ratite runner sharp-eyed soft-feathered symbol symbolic three-toed widespread wildlife