Years ago my husband and I were driving in the Northern Territory between Tennant Creek and Alice Springs, it’s a very long and often tedious drive. We’d been driving for hours and were looking forward to an overnight stop. It was approaching dusk when I saw a sleek, fawnish coloured animal with a very long tail move quickly across the road ahead of us and disappear into the bushes. I thought it was a Puma but that was crazy so I said absolutely nothing.
Some time later my husband suddenly said, “Did you see that?” I realized that he’d seen the same thing as me and for the same reason had said nothing. When we reached our stop for the night we still felt too stupid to ask anyone if they’d ever seen a Puma in the area. When we were back home though I looked on the internet and found there were several unconfirmed sightings in the eastern states of similar big cats but I didn’t find any reports of a light coloured one.
It’s a mystery!
There is some information here on sightings and possible explanations:
Musings of a Retiring Person 