Diel vertical migration (DVM) of young‐of‐the‐year (YOY) herring Clupea harengus and one of their major predators, pikeperch Sander lucioperca , was examined using bottom‐mounted hydroacoustics in Himmerfjärden, a brackish bay of the Baltic Sea, in summer. In contrast to previous studies on DVM of C. harengus aggregated across size and age classes, YOY C. harengus showed a reverse DVM trajectory, deeper at night and, on averag...