Attraction of Nontarget Species to Fruit Fly (Diptera: Tephritidae) Male Lures and Decaying Fruit Flies in Traps in Hawaii
Synthetic male lures are commonly used to monitor and mass trap pestiferous fruit ßies (Diptera: Tephritidae: Dacinae). However, there has been much dispute as to the nontarget impacts of such lures on beneÞcial and native insects. To evaluate nontarget attraction effects, traps baited with Cue-Lure and methyl eugenol were maintained and emptied weekly in a range of native and non-native forest and commercial orchard and backyard sites on Hawaii and Maui Islands. Lure trap captures were
... ptures were compared against those from unbaited control traps and traps artiÞcially baited with decaying fruit ßies to mimic the effect of accumulation of dead trapped target ßies in male lure traps. Cue-Lure did not attract nontargets, and methyl eugenol attracted low but signiÞcant numbers of Þve species of ßower-associated insects (honey bees, syrphid ßies, nitidulid beetles, and endemic crambid moths) and two endemic Hawaiian species of sciarids (Diptera) and mirids (Hemiptera). Saprophagous nontargets, mostly Diptera, were abundant and diverse in traps baited with decaying ßies and in male lure traps where accumulation of dead ßies occurred but not in male lure traps with few or no fruit ßy captures. Most of the previously published records of attraction to methyl eugenol are shown to actually be secondary attraction to decaying fruit ßies. Endemic nontargets were collected in native and adjacent forest, but almost exclusively invasive species were attracted to traps placed in non-native habitats. Attraction of ßower-associated species may be minimized if methyl eugenol traps are placed in trees after ßowering season in orchards.