Dennis Harris, who guides an electrofishing boat for a research contractor, is part of the science crew that briefed me last year at the world's largest known humpback chub hangout, just below the confluence of the Little Colorado River with the Colorado in Arizona. He spun a yarn about what fish say upon their return to home waters—how they survived an alien abduction. "They scooped me up in a net and took me to the Mother Ship and stuck me with a piece of glass and probed my genitals and brought me back here,'" Harris said, throwing his head back and splaying his arms to imitate fish stunned by the electric current. "And all their friends go, 'Yeah, right.'"