Efficiency of Two Gypsy Moth 1 (Lepidoptera: Lymantriidae) Pheromone-Baited Traps

pheromone-baited Pherocon IC sticky traps that were relatively free of captured moths caught about twice as many male gypsy moths as USDA milk carton traps during natural male flight and also in mark-recapture experiments with laboratory-reared males. Traps stapled to the trunks of trees captured more males than traps hung from small branches >2 m from large trees. Behavioral observations revealed three reasons for the higher catch at Pherocon IC traps. First, more males approached within 2 m of the Pherocon IC traps than the milk canon trap in a given time interval and a higher proportion of males engaged in pheromone-induced, zig-zag flight. Second, of those males that came in contact with either trap type, a higher proportion entered the Pherocon trap. Third, there were fewer escapes from Pherocon traps (10%) than from milk canon traps (28%). Milk canon traps captured 9.6% of those males that approached within 2 m and 44% of those that came in contact with the trap, compared with 20 and 76%, respectively, for Pherocon IC traps.