Use of fecal extract trails to enhance trap catch in German cockroach (Dictyoptera : Blattellidae) monitoring stations

An aqueous extract of German cockroach, Blattella germanica (L.),fecal mate rial was evaluated for inducing trail-following behavior in German cockroac hes. In arena tests the fecal extract was found to stimulate trail followin g in 74% of adult male cockroaches. Significantly fewer cockroaches (22%) f ollowed water-treated (control) trails. Residual activity of the fecal extr act trails was evaluated by bioassay after the trails had been stored in th e refrigerator or in the open air. Although trails stored in the refrigerat or showed no decline in activity after 14 d, those stored in the open air d eclined significantly after 3 d, inducing only 40% of adult male cockroache s to follow the trail. After 7 d the activity of trails stored in the open air was further reduced to 23%. The ability of fecal-extract trails to infl uence trap catch in monitoring stations was determined by bioassay. Paper t rails treated with fecal extract or water were positioned between cockroach harborages and monitoring stations inside 122-cm(2) arenas. The presence o f the fecal extract-treated trails significantly enhanced trap catch. Mean catch in the traps with fecal extract trails was 28 cockroaches compared wi th a mean of 11 cockroaches in the control traps. The trap catch ratios of adults to nymphs in the treated and control treatments were not significant ly different.