you might head over to tractor supply and set some stall mats under your run to head off digging under.
We set up a hardware cloth apron around the outside where there is bare dirt butted up to the fence. We haven't had a problem since we did that. The rest of the run has a floor in it.

We also nailed plywood against the fence where they roost to prevent little cat and raccoon paws from reaching in and grabbing any of the birds while they snooze.
Thanks for the advice!

MrsB