Effect of Verbenone on Attraction of Predatory and Woodboring

The response of bark beetle predators and woodboring beetles to the bark beetle anti-aggregation pheromone, verbenone, was tested in the field with multiple-funnel traps baited with attractant kairomones. Catches of the predators Thanasimus undatulus (Say), Enoclerr~~ sphegeus (F.) , Erwclaus lecontei (Wolcott) (Coleoptera: Cleridae) , and hcono tu .~ complex LeConte (Coleoptera: Colydiidae) declined significantly with increasing release rates of verbenone. Lmc~zotus ubcostulatzr.~ Kraus, and C0rtium.s praetmnis.ms (Fall) (Coleoptera: Tenebrionidae) (in two of three experiments), showed no significant response to verbenone. In a third experiment, catches of C. praeter$issus increased with verbenone dose. Likewise, catches of the striped ambrosia beetle, Trypodqndron lineatum (Olivier) (Coleoptera: Scolytidae), increased with verbenone dose in one experiment, but there was no effect in two other experiments. Verbenone had no effect on the response of Spondylis i ~ p $ m i s Mannerheim (Coleoptera: Cerambycidae). We hypothesize that predators specializing on early successional bark beetles are repelled by verbenone since this compound indicates a latdstage attack. Generalist predators and woodborers either do not respond to verbenone at all, or they may be attracted by it.