Beware of pickpockets as they tend to operate in tourist areas, keep your belongings secure at all times and be careful if strangers try to make conversation or distract you as it could be an attempt to steal your valuables.
Credit card fraud, cloning cards can be an issue be careful where you use your cards. Also if you are withdrawing money from cash machines make sure you cover your pin and be discreet about the amount of cash you withdraw.
House burglaries and break-ins are common crimes in Townsville, although as a tourist this is unlikely to affect you too much. Keep an eye on your personal belongings wherever you, and be wary on public transport.