@glyn: you've created a fairly popular thread here, and I assume that is testament to the fact that everyone loves bears of all shapes and sizes. People in Australia wish there were more bears in their zoos, and yet the sun bear program has a ton of potential for the future. A baby bear with a yellow crescent on its chest would be a gold mine in terms of both awareness and attendance.
When I visited Taronga Zoo one of the sun bears was pacing back and forth relentlessly, and it was pitiful to watch. The enclosure is full of logs and foliage, but it is definitely hidden away and more than likely many visitors bypass it completely. Isn't it true that the Perth Zoo has a decent, fairly new sun bear exhibit? That might be the one to copy for Taronga, but I'm sure that once the last brown bear dies off then the sun bears will simply be shifted to the empty enclosure.
I agree with some of the remarks concerning the welfare of specific bear species. In all honesty polar, brown and american black bears should not be kept in Australian zoos, and for Cairns to have some browns is nothing short of ridiculous. In all of the United States there are only about 250 grizzlies in Yellowstone National Park, and 98% of all brown bears in North America are found in either Canada or Alaska. It's freezing cold for most of the year, with constant rain and many snowy days. What does Cairns have to offer besides 40 degree summers?