Tuesday, December 12, 2006 - 2:23 PM
0875

Investigations of attraction of non-target insects to fruit fly (Tephritidae) female attractants and male lures on Hawaii and Maui Islands

Luc LeBlanc, leblancl@ctahr.hawaii.edu1, Roger I. Vargas, rvargas@pbarc.ars.usda.gov2, and Daniel Z. Rubinoff, rubinoff@hawaii.edu1. (1) University of Hawaii, Dept. of Plant and Environmental Protection Services, 3050 Maile Way, Honolulu, HI, (2) U.S. Pacific Basin Agricultural Research Center, USDA-ARS, P.O. Box 4459, Hilo, HI

Successful integrated pest management emphasizes the use of environmentally less toxic control methods for agricultural pests. However, it is possible that some of these more desirable methods may have unanticipated non-target impacts. This study evaluates the potential for such impacts in Hawaii’s Fruit Fly (Tephritidae) suppression efforts. Field investigations are underway to assess the possible attraction to fruit fly attractants along ecological gradients ranging from native, mixed and secondary forests to agricultural farmlands and residential areas. Traps baited with female attractants (solulys, torula yeast, Biolure 3-component lure) and male lures (Cue-lure and methyl eugenol) were emptied weekly at 35 sites along three transects on Hawai’i Island and 46 sites in native forest and persimmon and coffee orchards on Mau’i Island, during the 2005 and 2006 summer seasons, respectively. Trap catches were compared to catches by unbaited control traps. To minimize and assess the effect of decaying flies, propylene glycol was used as a liquid preservative in all traps, and traps baited with decaying flies were also maintained at most sites. Non-target insects from over 6000 samples are being processed. Male lures failed to attract insects other than target fruit flies, except for a weak honeybee attraction and probable fungus gnat attraction to methyl eugenol. Non-targets were abundant in traps baited with dead fruit flies, and the same species were also observed in male lure traps with large accumulations of dead trapped fruit flies. Protein attractants, Biolure and decaying flies, on the other hand, attracted large numbers of mostly Dipteran non-targets (mainly Drosophilidae, Calliphoridae, Phoridae, Sarcophagidae, Chloropidae and Lonchaeidae). Numerous native Drosophilids and Calliphorids were collected at traps were in native and adjacent mixed forest, but non-native species were attracted to traps set up in invasive forest, orchards, farmlands and backyards. Traps did not attract beneficial predatory or parasitoid insects.


Species 1: Diptera Tephritidae Bactrocera dorsalis (Oriental fruit fly)
Species 2: Diptera Tephritidae Bactrocera cucurbitae (melon fly)
Species 3: Diptera Tephritidae Ceratitis capitata (Mediterranean Fruit Fly)