It's funny mate, i've watched one of my jills cross a field like a beagle on the scent of a rabbbit that was missed and ran off, funny little creatures.
Also seen one try to climb a tree for the rabbits hung in it.
Aye mate, around here you could not ferret without a dog, it would do your head in, plenty of holes, but many of them well used but empty, with the rabbits lying up above ground. You need the dog to push them under and find them to ground. Wouldnt go out without one now to be honest.
When i was a kid (and not allowed to borrow the old mans dogs) i used to use a ferret to