Taking documentary photography to new HEIGHTS (Pun intended) Nature on PBS In the mountains of Mexico, a spy hummingbird ventures into the heart of a breathtaking monarch butterfly swarm. Spy in the Wild 2 - Episode Two: The North“ premieres Wednesday, May 6, at 8|7c on PBS. For full NATURE episodes, check out http://www.pbs.org/wnet/nature/episodes/
