Just to warn you - the 'gorilla lounge' room with the large window, that is adjacent to the outdoor living area is closed since the unnamed baby boy was born, so your views will be restricted to the (slightly more distant) outdoor area.
This is noted at the zoo's harbour entrance.
kaukau is right - get there for the feeding time (around 3PM).
It is after this time you will see everyone out and about, including Frala and her child.
We were 3-4 people deep, though, as everyone jostled for a camera position.
At other times you will be able to see the juveniles do their thing. They can be very playful not only with each other, but occasionally see some 'realatives' from the human side who they interact with. ^
(There are keeper talks and feedings especially 1.30-3.30PM, for reptiles, chimps, gorillas plus a morning and afternoon bird show).
To possibly maximise your ticket, wait for the seal/water show to open in 2008.
(If going on a Saturday, don't buy the SMH newspaper in the morning- get your free one at the zoo's info office. If you're in the city, buy your combined ferry/zoo ticket 'zoopass' on your credit card (AUD$88 for two adults)

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