For at least a decade, California has tried to restrict the use of rat poison so it stops killing all manner of creatures besides rats. So far, it hasn’t worked.
When a wild animal preys upon a rat that has ingested anticoagulant rodenticide, it can end up dead or sickened by the toxin as well. The poisoning continues up the food chain from predator to predator. Mountain lions, bobcats, foxes, coyotes, hawks as well as endangered species including the northern spotted owl and San Joaquin kit fox are among the wildlife that have been either killed by these rodenticides or made so ill that they can’t navigate their environment, hunt for food or dart across a road efficiently.