Distant-Dependent Capture Probabilities of Mediterranean and Oriental Fruit Flies (Diptera: Tephritidae) in a Food-Based Trap in a Hawaiian Mango Orchard

Abstract

Certain species of true fruit flies (Diptera: Tephritidae) are worldwide pests of fruits and vegetables, and many countries operate trapping programs to detect and monitor invasions. Food-based traps are an important component of detection programs because they are general attractants that are neither sex- nor species-specific. Torula yeast borax solution is a food bait that is used widely, but little is known regarding its attractiveness in terms of distant-dependent capture rates in field settings. The goal of the present study, which was conducted in a Hawaiian mango (Mangifera indica L.; Anacardiaceae) orchard, was to measure capture probabilities of oriental fruit flies, Bactrocera dorsalis (Hendel) (Diptera: Tephritidae), and Mediterranean fruit flies, Ceratitis capitata (Wiedemann) (Diptera: Tephritidae), released at 5, 10, or 20 m from a centrally located trap baited with torula yeast borax solution. For both species, capture probabilities were relatively low and decreased with increasing release distance from the trap. Trap captures were female-biased strongly in B. dorsalis, while the sex ratio of captured C. capitata was more variable and differed among the release distances. Based on data pooled over the sexes, B. dorsalis was captured at significantly higher rates than C. capitata for release distances of 5 and 10 m, and a marginally significantly higher rate (P = 0.053) for the 20 m releases. These findings are compared with other release-recapture studies of tephritids that involved food baits, and the relative attractiveness of torula yeast borax solution and male lures are noted for B. dorsalis and C. capitata.