We had a major infestation on the acreage the summer we built our house...managed to shoot a few,(got one with a framing hammer) but what really did the damage to their population was trapping. Used these...extremely effective.
Just find the hole at the fresh mound, open it up and set the trap. They don't like the light coming from the hole and will be back soon to "fix" that...usually get them first try.
Also works really well on Richardsons ground squirrel (sage rats I think you call them?) and thirteen lined ground squirrel...which we also get from time to time.
Hasn't got the wifes cat yet though...not 100% sure how I feel about that.