A fox does not attack a chicken run the way you would inspect one. It works at night, methodically, over many nights: biting at wire until strands part, digging where the soil is soft, shouldering at doors, climbing where there is anything to climb. Most fox losses are not failures of effort but of specification — a run built to contain hens, which is a far lower standard than a run built to exclude a fox. Predator-proofing means reviewing every surface, edge and habit with one question: what would a patient fox do with this?
Mesh that fox teeth cannot tear
The product sold as chicken wire is the first trap. Its thin, twisted strands keep hens in but part under a fox's bite and pull, sometimes in a single night. Use welded mesh instead — galvanised, with apertures small enough that a fox cannot get its jaws properly into the grid and young hens cannot poke heads through — and fix it taut to a solid timber or metal frame, because mesh stapled loosely to posts can be peeled. Check corners and joins where two sheets meet; a fox exploits the seam you overlapped carelessly. While you are at it, run the same eye over the coop itself: vents, pop-holes and nest-box lids all need the same mesh standard as the run.
Stop the dig: skirts and slabs
Digging is the fox's favourite route in, almost always starting right at the fence line. Two defences work. You can bury mesh vertically below ground around the perimeter, or — usually easier and just as effective — lay a wide skirt of mesh flat on the ground outside the run, pinned firmly and covered with turf or soil, extending well out from the fence. A fox digs at the base of the barrier and meets wire under its paws; few persist in backing up and starting further out. Slabs or a concrete strip around the base achieve the same for permanent runs. Whichever you choose, walk it after heavy rain, when scoured soil reveals the gaps and shallow spots a fox will find before you do.
Latches, doors and the top of the run
Foxes work latches. A simple hook, a loose bolt or a door that lifts slightly in its frame will all be found and used, so fit bolts that need a deliberate hand, and consider a second, different fastening on the main door. Gates should close flush with no climbable gap, and the pop-hole door wants the same treatment as the main door — it is the entrance hens use at the exact hours foxes hunt. Finally, look up. Foxes climb fences, lean-to roofs and adjoining structures, so a run open at the top is a run with a door in the ceiling: cover it with mesh or netting strong enough to take a fox's weight, and cut back branches and move bins or coops that give a launch point onto the run roof.
Dusk lock-up: the habit that saves hens
The strongest run in the county protects nothing at five o'clock if the hens are still scratching outside it. Most fox losses involve birds caught in the open at dusk, shut out by an automatic door that closed early, or left because someone assumed someone else had done it. Make lock-up early enough that the flock is in before dark, count heads rather than glancing, and check the pop-hole and latches by hand. Hens that dawdle outside need training back with a small feed scatter inside the run at the same time each evening, until the routine is automatic for them too.
Never let lock-up depend on memory
Dusk moves with the seasons, and busy households forget — which is why the final layer of fox-proofing is organisational. Making lock-up and the weekly mesh-and-skirt inspection assigned duties in KinsLe's Care Teams, marked complete with a timestamp, means one named person definitely shut the hens in tonight, and the run's defences get re-checked before a fox finds the fault.