Q: I heard that birds which eat poisoned rats could be killed by the toxin. Is this true?

A: Like a lot of situations, it depends on the chemical the rat consumed. Many poisons, but not all, are anti-coagulants. Some require a single dose to kill a rat and others need multiple feedings. To further complicate things, some chemicals are more toxic to birds than they are to mammals, like dogs and cats, that might find a weakened rat. Fortunately, the National Pesticide Information Center sorts it all out in the factsheet at bit.ly/ratpoison.