Factors Affecting Efficacy of Pitfall Traps For Beetles (Coleoptera: Carabidae and Tenebrionidae)2

Numbers of trapped beetles in the field and a laboratory arena increased with pitfall trap size. Size and configuration of guides affected catch size. Beetles which moved rapidly were more likely to be captured. Non-captures resulted when beetles turned away from traps or pulled out of the trap cones. Plant debris in traps reduced catch size.