There were animals out and about. The Western Meadowlarks were present in large numbers, trying to attract some mates. They have a most beautiful song, which I captured on a brief video that you can listen to at my Geotripper's California Birds site (click here).
The remaining prairies have persisted because no one could think of how to make money from them other than grazing cows or sheep. Now that almonds are a lucrative source of money, there is a target painted on the ranchlands in the Sierra Nevada foothills. I hope the state gets around to writing the groundwater regulations so we can get a handle on the unrestrained development that is taking place right now. It's clearly unsustainable in the long run.