I left the PRK (Cal) 5 years ago, however I was an avid hunter of birds in the riverside county area. Unless the law has changed in the last five years, Private Property had to be one of the following to be "off Limits" to hunting; posted,fenced or cultivated. I used to legally trespass with a gun all the time.
HOWEVER, herpin is fishing in the regs. Get a lic. and your good to go to carry a sidearm too (county areas) due to a law that allows open carry while engaged in lawfull hunting or fishing.
When I left you didn't need a lic. to take crotalus either. So If the fishcops bug you, tell them your looking for buzztails.