Seasonal flight pattern of the western balsam bark beetle, Dryocoetes confusus Swaine (Coleoptera: Curculioniae), in Central British Columbia

Art Stock, Terry L. Pratt, John H. Borden


Seasonal flight pattern of the western balsam bark beetle, Dryocoetes confusus Swaine, in stands of subalpine fir, Abies lasiocarpa (Hook) Nutt., in north-central British Columbia was monitored for three years using multiple-funnel traps baited with (±)-exo-brevicomin.  There were two major flight periods per year, the first commencing in mid- to late June, and the second occurring in mid- to late August.  The first flight was predominantly males, while the second flight was composed primarily of females, probably reemerged parent adults.  Little flight occurred until within-stand temperatures exceeded 15ºC.  Traps placed 6 m above ground caught 4 times as many beetles as traps placed 2 m above ground.  Our results indicate that semio-chemical-based manipulation of the western balsam bark beetle should be implemented by early May.


Coleoptera; Curculioniae; pheromone; trapping; dispersal; subalpine fir

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