I have the damned things digging in my garden. Short of shooting them
what can I do?

I have thought of covering the flower beds with netting but don't know
what type to use. Road bed mattress would allow the plants to grow
through. And so would barbed wire.

Any suggestions?

It's not even my garden I am guerrilla-ing it. I have something like a
tenth of a mile to look after so it could get expensive.

Road mattress (or whatever it is called -a fence lattice of something
like 4 inch squares used to reinforce roads) would just lay on or in
the soil and last a few years -long enough to establish thorny bushes.
Barbed wire would have to be supported off the ground.

Removing either for working on them could be a problem.