The light guage stuff surrounds about a quarter of an acre (also serves as
the orchard) and I have gradually moved right round it putting a heavier
guage wire right round it to about waist height - that has worked (so far)
but it took me a year or more to do what with one thing and another.

As you can imagine with a fence of that area, I have been able to keep a
good eye out on the fox activity.  They seem to spend days putting pressure
on one area.  For a few days it will be an indentation and scumbled earth
near a site they are working on, then a single broken wire will appear and
then over a few days a gradual and increasing number of broken wires till it
is obvious that they have made an incursion.  They can get through amazingly
small holes.  It's at that stage that I've repaired the holes.  I like to
let them waste a lot of time.

The other thing the bozos did when they built the fence was that they didn't
either bury about a ft of wire or lay the wire out on the ground for about a
ft on the foxward side.  I've now done that as I went around, so far so
good.