Time of day is also HUGE. The days tend to be hot, and the nights cool, so during the hot part of the day the herps tend to go deeper under ground to maintain a not too hot temperature. So after things warm up you aren't likely to find anything on the surface, or under anything you could flip. BUT, since the nights are cool, it is very likely that snakes will come up long enough to get warm again, so you want to be out flipping boards and rocks in the morning. Most animals won't need to lay in direct sunlight the temp under a rock or board will be plenty, and that way they won't need to expose themselves to predators. Plan to be get out early (7:00 am?) and flip boards and rocks, carpet, trash, until it gets hot (> 80) After that you are can still find lizards, but most snakes will be deep. So either use that time to scout for good spots to try the next morning, look for lizards, or pack it in.