To outpace the Australian bush fly you need to be travelling at at least 15 kilometres per hour. This is doable on a bicycle but impossible on the Cradle Mountain - Lake St Clair Trek, which is only accessible on foot and, taking about six days to complete, requires a fair-sized, pace-slowing rucksack to boot. Why this particular fly would want to use high-speed air currents to migrate from South Australia to Tasy every summer is a mystery to me. Unless it`s to annoy trekkers of course. The fact that a fly`s life is measured in but a few days is very gratifying. He might make that journey only to be grounded by bad weather for the rest of his futile life in this, much the wettest corner of Australia, but also one of its finest.