Radiolab

Ecologist Nick Haddad was sitting in his new office at North Carolina State University when the phone rang. On the other end of the line was... The U.S. Army. The Army folks told him, “Look, there’s this endangered butterfly on our base at Fort Bragg, and it’s the only place in the world that it exists. But it’s about to go extinct. And we need your help to save it.” Nick had never even heard of the butterfly. In fact, he barely knew much about butterflies in general. Nonetheless, he said yes to Uncle Sam. “How hard could it be?” he wondered. Turns out, pretty hard. He'd have to trick beavers, dodge bombs, and rethink the fundamental nature of life and death in order to rescue this butterfly before it disappeared forever. **CORRECTION: An earlier version of this story incorrectly stated that the Army moved a beaver; in truth, they killed it.  We also overstated the current tally of St Francis Satyrs off range; they are around 200, not 800. The audio has been adjusted to reflect these changes.**This episode wa