Killing livestock is an issue, but killing humans isn&#x27;t really; it&#x27;s essentially in the &quot;freak accident&quot; category, and less common than even most rare sources of freak accidents. So far, at least, the reintroduction process in the lower-48 U.S. states (which has been going on for about 20 years) hasn&#x27;t led to any attacks on humans at all. If you include Alaska, which has a native wolf population, there&#x27;s been exactly one wolf fatality in the U.S. in the entire period since WW2.<p>As for crocodiles: There&#x27;s quite a bit of effort being expended to protect the declining crocodile population in Florida, so I don&#x27;t think it&#x27;d be categorically out of the question.