I went back and read what the excerpt that you posted. That's not what it says. It says "predatory animals or livestock-killing dogs" and does not say that the predatory animals have to prey on livestock. It says dogs have to be preying on livestock to be covered under the exception to be poisoned. All other predatory animals are fair game as long as the sign-posting requirement is met. Did they post any signs?
No they did NOT post signs. This is NOT a ranch it is a house in the suburbs ... no livestock is allowed here. The houses back up to the San Jouquin river where there is a lot of wildlife ... ALL of it protected. Once again domestic cats are NOT recognized as predatory animals in the sense that the law refers too anymore than my neighbors teacup poodle is.
and also you are missing the point. These people did NOT set out poison because they had a predator problem or even had a cat pooping in their yard problem. There are no backyards here. The decks overhang a PUBLIC river. Wildlife like ducks and geese live in the rushes and reeds under the decks and it is ILLEGAL to molest them. That includes the neighborhood pets. They poisoned the cats to get back at the neighbors as part of the years long feud we all have been having.