The technical and performance characteristics of a low-cost, simply-constructed, black light insect trap

Mercury-vapor black-light (MVBL) funnel traps have demonstrated a great capacity to survey moth assemblages and other nighttime insects in a variety of habitat types. They have been used in applications ranging from quantifying the impact of habitat fragmentation on forest insect assemblages, to monitoring the presence and prevalence of agricultural pests. Typically, MVBL funnel traps are constructed of a mercury vapor black light bulb, powered by a car battery. When used at night, insects fly towards the low wavelength black light, strike one of three plastic vanes extending out from the light, and then fall into a funnel trap where they are collected. While effective, these MVBL funnel traps cost $250 or more, per unit. This can quickly become prohibitively expensive as research projects often require a dozen or more traps running concurrently in different locations. As a result, moths can be an impractical taxonomic group to study, particularly when research budgets are limited. To address this problem, we designed a simply constructed and cost-effective trap using plastic bottles and LED black lights, powered by rechargeable 9V batteries. We tested our new LED-based funnel (LEDF) trap in the spring and summer of 2015 and found that it had an overall moth catch yield of 50% to 70%, compared to MVBL funnel traps. Though it demonstrated this reduced catching efficiency, it cost less than $33.00 per trap to construct, making it a reasonable low-cost alternative to MVBL funnel traps. Here, we present the technical and performance characteristics of our new trap design.