I've heard the same from many. Once you learn their...foibles you'll see them as often as any other, only in a shorter time window than those with whom they share habitat (sharptails, boas, garters, gophers, racers, ringnecks, rattlers, etc. Even calkings.)
The only hint I'll offer is that regardless how optimal the conditions might *seem* in other regards, if you don't see western skinks you won't find zonatas. But I only explore the Santa Cruz Mtns so my observations may not hold true throughout the state.
Cheers, SA
PS: REMEMBER TO REPLACE ANYTHING YOU MOVE. ONCE THE "MOISTURE ENVELOPE" IS BROKEN, THINGS WILL DRY OUT AND SHORTEN THAT ROCK OR BOARD'S USEFUL LIFE FOR THE SEASON.
