There were 32 different Directors of Photography during the shoot. The idea was to have a different D.P. for every new place that Bubby went to not only give the film more of an experimental feel, but also to eliminate the worry of having to always have the same crew on set every day.
The feral cat killed in the movie was killed humanely by a vet, and not suffocated as depicted in the movie. The same cat was used both when it was alive and after it had been put to sleep. The kitten depicted to be killed later in the movie was not feral, and was not really killed, it was only sedated.
During shooting director Rolf de Heer heard a rumor that the Australian government might legalize the death penalty. Outraged at this, he wrote an alternate ending which featured Bubby being arrested and hanged for his crimes. de Heer eventually changed his mind and the ending was never shot.
The original idea was for the first half of the movie (the scenes in Bubby's house) to be shot with the left and right sides matted, to make the viewer feel more claustrophobic, and then when Bubby finally goes outside the picture was going to expand into full widescreen. Rolf de Heer decided not to do this because he felt it made the first half of the movie unwatchable.