Abstract: A fishline jerking device includes an elongated casing having a first loop at one end and a longitudinally movable rod projecting from the other end of the casing. The rod is terminated with a second loop enabling a fishline to be serially double wrapped about the two loops. A spring about the rod urges the rod to move rearward to a position where a contact carried by the rod engages a contact carried by the casing to complete a circuit with a battery and lamp as a fish bite signal. The rod is normally retained in a forward position by a releasable spring loaded catch. In response to a side thrust exerted on the second loop by the line, the rod passes the catch and snaps rearward to jerk the line. A pointer carried by the rod cooperates with a slot in the casing and graduations along the slot to form a scale.