Effects of carbon dioxide, an octenol/phenol mixture, and their combination on Tabanidae (Diptera) collections from French 2-tier box traps

The French 2-tier box trap was evaluated in northwestern Florida to determine its attractiveness to host-seeking tabanids (Diptera) when baited with either CO2 alone; a 4:1:8 mixture of octenol, 3-n-propylpbenol, and 4-methylphenol; or a combination of CO2 plus 4:1:8 mixture. Six genera representing 43 species were obtained from this trap. Chrysops and Tabanus made up 10.3 and 87.4% of the total, respectively, with Chrysops celatus Pechuman and Tabanus pallidescens Philip as the predominate species from these two genera. CO2 alone and in combination with the octenol /phenol mixture enhanced overall tabarrid collections three-to four-fold compared with no odor. Generally, more species were collected in the top tier of the French 2-tier trap regardless of treatment. Those species that showed a significant difference between top and bottom tiers in traps without odors continued this trend when traps were baited with the semiochemicals. However, Tabanus mixis Philip showed no tier preference in traps baited by CO2 alone, whereas Tabanus lineola F. showed no stratification difference with or without odors.