What do the man and the woman talk about?

W: Bird watching! Now what is it people love about this so much?
M: I think it’s the challenge, it keeps your brain going, you feel like a little kid on a treasure hunt. You’re poking around the trees, and looking for little hidden birds.
W: The three central characters in your book, the top finishers in the 1998 Big Year competition, were clearly looking for a challenge. Tell us how the Big Year works.
M: Well, the Big Year is a contest with no referees and few rules. The idea is, who can see the most species of birds in North America in one year. So you can see them however you want. You can fly to see them, ride a bike to see them. In one case, they even took a helicopter to see them in the Ruby Mountains of Nevada.
W: And they chase the birds through the canyon, as I recall.
M: They did, up and over peaks, and one guy had a horrible seasickness problem.
W: It is said he just hoped he could hold his breakfast together.
M: And he did, and he got the bird. What a great bonus.