The Taber-Keller trap: a modification of the Berlese funnel to entrap flying insects

The Berlese funnel is an apparatus developed by Antonio Berlese to extract small arthropods from leaf litter, soil, and other organic materials. The basic apparatus is a funnel that contains medium sized wire mesh upon which organic material is placed. Beneath the funnel a vial containing alcohol is attached to catch and preserve the specimens that try to escape the drying leaf litter for later examination. Albert Tullgren modified the Berlese funnel by placing a light bulb above the funnel to accelerate the drying of the material and to force the specimens toward the vial at the bottom. But neither the Berlese funnel nor the Tullgren funnel addressed the escape of flying insects from the trap. To prevent the escape of flying insects from the Berlese funnel, an extension (called the Taber-Keller trap) was developed and tested in our lab. The extended structure consists of a tent-like pyramidal-shape with a collecting container on top to capture flying insects that would otherwise escape. Two experimental trials were conducted and evaluated. Initial design problems, such as the hole size of the netting were observed; however, results were very promising showing the potential of the trap to catch flying insects. A third experimental trial is currently being conducted and a fourth run with an improved design of the Taber-Keller trap is planned. Data from these experiments will be presented and evaluated to show the advantages of this modification not only for entomologists but also for more complete arthropod biodiversity analyses using Berlese funnels.