When a hawk, owl or eagle eats the rodent, it gets the poison from the fur. Eagles and other raptors are at the top of the food chain. So are we. The eagles nesting in Wausau swoop down to scoop up fish from the Wisconsin River. It is the same Wisconsin River that anglers ply, the same river that flows through Rhinelander, Merrill, Stevens Point and Wisconsin Rapids.
Humans share nearly all of their DNA with lesser animals.
Toxic effects show up sooner in birds because their generational succession is faster-paced. They're considered safe, and thus are overused. If so, that is your choice. But you need to understand that there are consequences and understand your actions affect the world around us. You are next.