Covered by Wide World of Sports, National Public Radio, and National Geographic, Texas rattlesnake roundups like those in Sweetwater, Texas, draw both fascinated tourists and irate protesters. Begun as an organized form of predator control in the 1920s, for many years rattlesnake roundups have been promoted as community events and civic fundraisers. The western diamond-backed rattlesnake is the main attraction, with pits full of thousands of writhing rattlesnakes serving as the featured spectacle.

Often taking advantage of the animals' denning behavior to capture large...