electric fencing is fantastic, we hav had no fox get in ever since the first day we put up out electric fence around 5 years ago. its main powered and usually if the fox hits it he does not often risk coming back. we have a 60 meter netting fence and then just as an extra precaution we have a single strand of white electric wire 1 foot out and 1 foot high from the electric fence and its brilliant. never need to worry about shutting them in.