The Result Is Clear: Color Trap Preferences of Adult Necrophagous Flies

Color vision plays a critical role in Diptera behavior, particularly in the detection of oviposition sites. Necrophagous Diptera, like the Calliphoridae, are of forensic importance because the larvae are commonly used to estimate minimum postmortem intervals of human remains. To better understand which species are present, flies are routinely sampled in different habitats using baited traps; however, the influence of trap color on capture efficiency remains poorly understood. In this study, baited bottle traps painted clear, blue, red, and yellow were deployed in wooded habitats to collect adult dipterans. Overall captures were dominated by Lucilia coeruleiviridis (Diptera: Calliphoridae). Clear traps consistently captured a greater diversity of Calliphoridae, Muscidae, and Sarcophagidae. In contrast, yellow traps captured the fewest individuals overall, while red and blue traps yielded intermediate numbers. Dipteran composition in red and yellow traps, however, differed from those in clear traps. Collectively, these results indicate that clear baited traps are more effective for sampling adult necrophagous Diptera, whereas yellow baited traps may be less suitable. Additional investigation is warranted to characterize the complex interactions between visual and olfactory cues underlying attraction and oviposition site selection in necrophagous dipterans.