Coyote,
She CAN bark and does occasionally, but for the most part you here not a sound, like strangers can knock on the door and she doesn't bark - I understood that dingos don't bark. I heard that sheep dogs bark and cattle dogs are mostly silent. Nope no surgery on her vocal cords, though sometimes when I say speak she only manages a cough...

A neighboor saw her and said her queensland heeler mix also had the red speckles on a white body with a couple big plain red patches.