Yellow Water Billabong is well known for its wildlife. Birds, in particular, congregate around the billabong towards the end of the dry season. The boat tour guide knew the names of quite a lot of birds. This was just as well, since there were obviously some rather keen bird-watchers on boards making logs and discussing among themselves what species a bird was and what they resembled.
It turns out this bird is a rainbow bee eater. Thanks for the identification, Bea!