Lightning is a major agent of disturbance in tropical terrestrial ecosystems, but its effects often are overlooked or misidentified in lowland forests.  We used an unmanned aerial vehicle (i.e., drone) to locate 12 probable lightning strike sites in ca. 47 ha of forest in the Peruvian Amazon.  Subsequent ground-based surveys of the 10 accessible sites revealed 7 that were unambiguously caused by lightning.  The seven sites included 121 lightning-damaged trees, 45 of which were dead.  Large trees (>60 cm in diameter) were disproportionately affected by lightning.  The numbers of trees damaged and their size distribution were comparable to results from a comprehensive study of lightning damage in Panama.  By contrast, post hoc surveys of lightning gaps in Brazil and Malaysia documented 3-5 times more dead trees per strike, suggesting that gap-focused surveys are biased towards larger disturbances.  These findings contribute to a growing body of evidence that lightning is an important disturbance pantropically, and that accurately documenting the effects of lightning requires reliable identification of lightning strike locations.