I'm from Australia, and can tell you that for sure they can free range, but as ES Emus says, don't expect to see them again. They are nomadic birds and don't hold territory; being desert birds they must wander in search of food which is only found in small amounts and rapidly depleted in any area they visit. Chickens however do naturally hold territory in the wild. Hence the ability to have free ranging chickens but the necessity to fence emus in.
They go through normal paddock fencing without a problem (until the odd one tangles and gets hurt) but maybe an 'invisible' boundary fence would work? (Just a random idea). If a proper fence is too expensive, what about those ones they use for dogs; not the sort that shocks, but the sort that interacts with a collar on the animal which buzzes or makes a sound or even a mild shock when the animal gets within a set distance of the boundary. This would be an easier way to give them some unfenced acres. But there's a good chance, being birds, and being fast birds, that they'd still speed through the fence despite any shocks, and they may not be smart enough to understand the shocks accompany whatever visual markers you put up... Maybe not a good idea... I don't know.
Anyway, best wishes. I too hope to keep ratites in future. But I'm hoping to do it with deer fencing.
