well apart from foxes we dont have any of those scary animals u listed in australia! lol! Ive seen lots of harmless animals while trail riding like kangaroos, wallabys, lizzards, goannas, rabbits, rats and mice. Ive come across a few snakes but most of the time they just run away and i just keep my distance from them. I dont think foxes would do much, i think they would just run away. I have come across a pretty scary looking dog but i saw it before i got close so i just turned around. Once i heard a really scary growling kinda noise in the bush right next to me and i just turned around and bolted! lol! that was scary!!! to answer your question, i would just turn and run! Im not sure if its the right thing to do but i would just do that without even thinking!