Understanding the movement patterns of stored-product insect pests within a food processing or storage facility is important in terms of identifying and targeting pest management at sources of infestation and determining their potential to avoid pest management tactics. In this case study, we demonstrated using a mark-recapture technique that the red flour beetle, Tribolium castaneum, was able to move among floors within a flour mill, but the majority (86%) of beetles were recovered on the same floor on which they were marked. For individuals that moved to a different floor, most moved downward (70%) and typically only to an adjacent floor (87%). Use of heat treatments to disinfest structures is an important pest management tool, but insects have the ability to move away from unfavorable temperatures. During a heat treatment of the mill there was an increase in the number of beetles captured, indicating increased movement, but there was not an increase in movement of marked beetles between floors. These results suggest that the rate of heating was sufficient to not allow the beetles time to move to cooler floors and escape the treatment. Results of this study indicate that red flour beetles are mobile enough that sources on other floors need to be considered in making pest management decisions.
Contact James Campbell, telephone 785-776-2717, email James.Campbell@ars.usda.gov