I think so
Foxes can't chew through wire, they tend to break door catches or pull the wire off at a corner if it's only fixed to the wood with staples.
Best thing to do is to check that the wire is well nailed on (if not, you can reinforce it with fencing staples from the DIY store) and also fit some bolts to the door.
I thought ours was well secured and have been putting bricks to weight everything down as well as clips etc but somehow a fox or something managed to break the whole side of the run and got our lovely Rolo...we are so devastated. Cookie look absolutely lost and from now on I'm afraid Cookie is going to be locked in the hutch itself every night. For a year and a half now they have been able to get into the run as I thought we had done everything possible to secure it, so I guess I just want to say be careful as we are devastated....
Debbie
Our poor Rolo..RIP