The Wikipedia article about San Francisco's Barbary Coast old red light district says, under the heading "Sidney Town":
By the end of 1849, several ships from Australia brought former members of Great Britain’s penal colony – including ex-convicts, ticket-of-leave men, and criminals – to San Francisco, where they would become known as the Sydney Ducks. These Australian immigrants had become so numerous that they dominated the neighborhood. They opened boarding houses and various types of groggeries which had prostitutes affiliated with their businesses.
These individuals had originally been taken to Australia as part of the British penal transportation mechanism that was operated from 1788 to 1868, described in this Wikipedia article.
The question I would like to ask:
Why were these ex-convicts, ticket-of-leave men, and criminals moved from Australia to San Francisco?