According to the NSW Road Rules (46 and 48), before a driver changes direction to the left or right they must give the corresponding 'signal' (by using the indicator) for long enough to give sufficient warning to other drivers and pedestrians. If moving from a stationary position at the side of the road, or in a median parking strip, it must be for at least 5 seconds. This is provided the vehicle is fitted with indicators.
A 'change of direction' (rule 45) is stated to be:
- turning
- changing marked lane
- diverging
- entering a marked lane or line of traffic
- moving from a stationary position
- turning into a marked lane or line of traffic from a median strip parking area
- at a T intersection, where leaving the curving continuing road to enter the other road (even though it proceeds straight ahead)
By those rules, I would say that yes you must indicate when turning.