I think it was Hugh fearnley wittingstall who suggested hen tree houses. About 8 ft off the ground - you need a ladder to collect the eggs. You lay the ladder on the ground the rest of the time. You train the chickens to fly in and out. I think you start with the coops lower to the ground and accessed by a ramp, then raise them and add a ladder, then take the ladder away and they fly in. . . . . . .

I saw a programme where badgers can climb vertical fences and pergolas.

A badger who rips off doors and get through mazes. . . . . . I always heard that if you hang a short length of dangly chain over the entrance of the chicken coop the fox (not a badger) thinks it's a trap and doesn't enter. . . . . . seemed to work on the hen house we used to have - but I wouldn't like to rely on it.