PW: This most recent book, Fly-Fishing the 41st, as a travel memoir, is a departure from your previous ones. What inspired this title?

James Prosek: It was fishing trout at the headwaters of the Tigris River. I first got the thought of fishing there during my freshman year in college. I was reading Paradise Lost and thought that it would be cool to catch trout where Eden was.

PW: This is your fifth book with as many publishers. What has made you change?

JP: It seems that the publishing business is different than it used to be, in that an editor and author no longer stay together for a long time. The first book I wrote was when I was in college, Trout: An Illustrated History, and the editor was Gary Fisketjon at Knopf. Then I got an agent, Elaine Markson, and she sent Rob Weisbach at William Morrow a book called Joe & Me. My third book, Early Love and Brook Trout, was with Lyons, and, finally, Complete Angler, was at HarperCollins. (Now, three of them are all under one roof.)

PW: Did you feel you found any new species or subspecies of trout while you were in Turkey, where part of Fly-Fishing the 41st takes place?

JP: Well, this is a big question. There are species like the brown trout, which are very diverse, but it's difficult to categorize things that are in a constant state of evolution. You can't always fit things into neat little boxes. I did find some unusual trout, especially in Turkey, which I could possibly write an academic paper on. My solution, though, is to choose 100 trout, as I did in Trout, that look very different and to paint them. In my opinion, painting fish is a very pure form of scientific work.

PW: Your sister, Jennifer Prosek, is your publicist. How is it working with family?

JP: Initially, she helped a lot with publicity—and still does. I was reluctant to publicize my first book, but she taught me that you have to push what you've created to help get it off the launching pad. I'd spent four or five years researching and writing Fly-Fishing the 41st; after that much time, you simply want to get it into the hands of people.

PW: How have you felt about competing trout books?

JP: I think Behnke's is a beautiful book (Trout and Salmon of North America). I admire the book a lot. It's very pretty, and it has information that's not in my book. If I were to say that mine is the definitive book—that would be very selfish. My only hope for my books is to expose people to the world of trout.

PW: Who is the audience for fly-fishing books?

JP: For this book, I'm hoping the audience goes beyond just fly fishermen. For me, fishing is a vehicle for learning about places and people. I, myself, don't know how much further I can push the fly-fishing idea in books. I think this journey is sufficient for now. So I like to think of this book as a departure. It's more of a travel book—a book about strange people and a strange passion.

PW: What was your favorite fishing spot in the book?

JP: I enjoyed fishing in downtown Paris, because it was a way to become comfortable with the city. I also enjoyed Japan's beautiful streams, but not all of these places have nice fishing. Slovenia has both nice streams and good fishing.

PW: Which spot was the most familiar to home and why?

JP: There were two places: a stream in western Turkey that flowed off of Mt. Olympus looked so much like my house in Easton [Conn.]—the foliage was very familiar. I felt very at home there. But the stream I would go back to is in Spain, which is at the headwaters of the Tajo River, the longest river on the Iberian peninsula. And it was totally full of trout.