Vertical Redistribution of Black Soldier Fly Larvae (Hermetia illucens) Under Restricted Airflow

The black soldier fly, Hermetia illucens (Linnaeus, 1758), is a globally farmed insect reared to convert organic waste into useful biomatter and materials. While research on optimizing bioconversion rates and larval development through substrate manipulation has surged, studies on larval behavioral responses to abiotic factors lag. This benchtop-scale study is the first to examine larval behavior in response to reduced airflow. The results suggest third to fifth instar H. illucens larvae, which typically burrow within the substrate and avoid the surface, are significantly more likely to aggregate at the surface of their substrate when in a restricted airflow environment. More than half of third instar and nearly all 5th instar larvae aggregated at the surface when airflow was restricted, compared to less than a quarter under ventilated conditions. This data should stimulate future directions of hypothesis building in larval behavioral and physiological responses to airflow with the goal of using behavior modification to facilitate larval production.