As part of the Transperth network is a ferry that takes you to South Perth, which is where the Perth Zoo lies. Those ferries run typically every half hour, or every quarter hour in high times. Besides Transperth ferries, there are ferries that can take you down to Fremantle and further on to Rottnest Island. In addition, it is possible to take a ferry as part of a wine or river cruise option along the Swan River.
The ferry terminal in Perth is located at the Barrack Street Jetty, down near the Swan Bells Tower.
Taxi cabs are plentiful in the Perth area, and they are all run on metered rates. You can take a taxi from the airport to the city center in around 20 minutes for a cost of $20 to $30.
If you wish to catch a taxi, you can flag down the available cars that have an illuminated sign, or find a taxi rank, such as at the airport. The Swan Taxis and the Black and White Taxis are popular in the area.
There is a zone in the Perth city area where riding buses and trains is free. When it comes to riding the bus, you do not need to have a Smartrider card to go for free. While riding the trains, however, non-Smartrider card holders will have to purchase a 2-section ticket fare (so, not free). You can see the map of the bus and train FTZ zone here, and you can get more information on the FTZ here.
Photo credit: 1, 2, 3.