I started reading this book in August, within two weeks of the date when Robert Michael Pyle set out on his journey to follow the monarchs on their migration. The brilliance of his writing is in the way he captures the colors, textures, sounds, and smells--the FEEL--of the landscapes he's traveling through. I was already reading in the right season, with the approach of autumn, and this book really transports you to the overgrown fields, river banks, starlit nights he experienced on his road trip. It also takes you to totally unfamiliar environments, like the Bonneville salt flats. I've never seen them in real life or pictures, but I now have a crystal clear mental image of what they're like.
The book is full of many fascinating things about monarchs: my favorite, that their Latin name may be taken from the girl Danae in Greek mythology who is so beautiful that Zeus comes to her in a shower of gold. Plus a lot of aspects to the insect that are more scientific but no less poetic in his recounting of them. Pyle is *passionate* about butterflies, and his childlike sense of wonder is contagious. You get the distinct perception that the world he's traveling in is much richer than other people's, because he's seeing so much more. Every fleck of color that flits by on the wing is identified by him and its life history briefly told. He's a true naturalist with encyclopedic knowledge.
His trip was an ingeniously simple idea: There's a lot that's still not known about the monarch's migration in the West, and he set out to learn more and either prove or disprove one of his theories about it by physically following the butterflies as they migrate to see what paths they followed. He would net a butterfly, tag it, then watch to see what direction it was flying when it disappeared from his view. Then he drove that way.
The one caveat of this adventure is that he actually saw and followed much fewer butterflies than he seemed to expect (or that the reader could hope, to make the whole tale more exciting). His timing seemed to be a little off--a few locals even tell him that they saw many butterflies pass through just a week or two before, when he himself finds none. So the book is filled (especially towards the end) with all the anticipation, yet frustration of several consecutive near-misses.
Still, his rich, detailed nature writing and all his other discoveries along the way make this book absolutely worth reading. I wonder if anyone has ever followed the rivers of the West via land the way he did.