Petri plates (PP) containing volumes of media attached to unmanned aircraft systems (UAS) have been used to trap atmospheric biota for years. If capture efficiency varies based on media volume used, aerial concentrations of biota may be poorly estimated after an UAS flight occurs. We conducted 36 separate sampling flights in which PP were filled either with media to maximum volume or half the maximum volume to determine efficiency of each in the collection of viable spores from the genus Fusarium in the lower atmosphere. Overall, the media at maximum volume collected 56 % more spores than the media at half-volume when analyzing the average collection for all flights. In research that relies on quantification of an aerial biota source, UAS equipped with media-containing plates filled with less than maximum volume will hinder spore collection efficiency.