'Like the emus, I guess they follow the food.'
And the permanent water.
[Mustang poop just twenty feet from the car port this morning. The mustangs were in my 'backyard' last night.]
So, we don't observe the brumbies as such; but your point is a valid one:
remember that we pretended to be emus on the old Oudman place? and we thought about what areas we know, and what areas we didn't, and where we might go?
Well, surely the brumbies use the same equation. They surely have memories of food sources and permanent water. And they surely make decisions about moving across their territory on that basis.
SE