As the sun tucked itself beneath the horizon, all was still on Michigan’s White River. Kandace Griffin, a fisheries and wildlife doctoral student at Michigan State University, sat on her gently bobbing research boat, listening to the evening chorus of frog croaks and red-winged blackbird songs. Every so often, a series of sharp taps emitted from a small speaker broke through the natural sounds, signaling that a sea lamprey—part of an experimental group she’d tagged earlier—was weaving through the depths below.
