Most 19th Century BDM's that I have seen have a section "Time in Colony/State" and refers to persons from overseas ie not native born. In answer to "Birthplace of Father or mother", quite often, particularly with Convicts, it is common to have the name of the ship they came to Australia in, rather than a place name. A person 'Native Born" is one who is born in Australia, usually of European parents.
Mickcee