The inventive subject matter is directed to pest detection systems that implement infrared emitters with detectors that look for variations in incident light indicative of wingbeats from various pests. Emitters and detectors are placed on one or more printed circuit boards such that infrared light projected from an emitter can be received by one or more detectors. Based on signal generated by a detector, systems of the inventive subject matter can determine whether a pest has flown between an emitter and detector. To save on power, emitter, detectors, or both can be driven by pulse width modulation. Methods of the inventive subject matter are directed to determining pest presence via signal filtering and interpretation.