When we arrived, there were thousands (possibly tens of thousands) of them hanging from the eucalyptus trees on either side of the river. A few were flying around from tree to tree, and others were waking up and stretching. They got noisier and noisier, and more and more restless, until after sunset the air was full of bats...
I'm definitely not used to being around wild animals other than birds, so it was quite disconcerting at first. Some of the noises they made were especially eerie! Luckily the bats weren't interested in us at all - they stayed well up in their trees and sky.
I took these photos (and video) on my phone, which is why they're a bit dodgy - although I think the blurry motion effects are cool! We'll have to go back again soon with a video camera. Apparently there are also echidnas in the park, and lots of birds, so perhaps a daytime trip too. Now that Willie has a driver's license, we can take advantage. ;)
Apparently these bats used to live in the Botanic Gardens, but had to be relocated "due to the sensitive nature of the vegetation". I wonder how one relocates a colony of bats?