After calling the council I went up the garden to see what the fly situation was.
Bloody fox has gone/moved !
I can't think what would be big enough/strong enough to move it - apart from maybe the badger that hangs around there sometimes.
Having said that, can't see why the badger would be interested in a smelly fox ?
Graeme - as you're one of my mates, you're welcome to come and get the fox for a barbie if you want