Attraction of Mediterranean fruit fly, Ceratitis capitata (Diptera: Tephritidae) and non-targets to the attractant BioLure and its individual components in Hawaii

The attractant BioLure is commonly used to monitor populations of Mediterranean fruit fly (Medfly), but may also be used, in combination with protein bait spraying, as a control tool on host crops. BioLure uses a combination of three harmless chemical components: ammonium acetate, trimethylamine hydrochloride and putrescine. MultiLure traps baited with 3-component BioLure were maintained and emptied weekly in native, ecotone and non-native forests, farmlands, orchards and residential areas, on Hawaii Island (36 sites in 2005) and Maui Island (46 sites in 2006), to assess its attraction to non-target species in a broad range of Hawaiian habitats. On Maui, traps baited with two components were also used at the agricultural sites, with hope to exclude the putrescine ingredient without reducing Medfly attraction. Additionally, attraction to the three separate components was compared to the combined components in native forest, a citrus orchard and a coffee plantation. A propylene glycol solution was used as liquid preservative inside traps. Large numbers of over 250 species of mainly saprophagous non-targets (primarily Drosophilidae, Chloropidae, Lonchaeidae, Calliphoridae and Sarcophagidae) were attracted to Bio-Lure. Native species were attracted in large numbers whenever traps were set up in endemic forest, but mostly invasive species were collected in orchards, backyards and non-native forest. Beneficial predators, parasitoids or pollinators were not attracted to BioLure. Ammonium acetate was determined to be the component most attractive to both Medfly and non-targets. Omitting the putrescine ingredient did not drastically decrease Medfly catches.