RESPONSES OF MALE SPRUCE BUDWORM (LEPIDOPTERA: TORTRICIDAE) TO DIFFERENT CONCENTRATIONS OF SEX PHEROMONE AS MEASURED IN A SUSTAINED-FLIGHT WIND TUNNEL

Abstract
Responses were recorded of male spruce budworm (Choristoneura fumiferana (Clem.)) exposed to natural pheromone and a wide range of concentrations of synthetic pheromone in an all-glass wind tunnel equipped with a moving, patterned ceiling. The numbers of males wing-fanning and plume-following decreased with decreasing concentration of the pheromone plume. Speed of upwind flight with the ceiling stationary increased with decreasing concentration, but the durations of flight sustained by moving the ceiling were not significantly different under the different concentrations.Males exposed to pheromone produced by calling females showed a higher incidence of plume-following, and flew significantly faster, than males exposed to a similar concentration of synthetic pheromone.