Comparison of yellow and white pan traps in surveys of bee fauna in New South Wales, Australia (Hymenoptera: Apoidea: Anthophila)
Pan trapping is a standardised and commonly used method for collecting bees, but characteristics of the trap may influence its effectiveness or bias results. The effect of trap colour on the species and numbers caught has been studied in the Northern Hemisphere, but not in the Australian region. Australia has a unique bee fauna and colour preferences, if any, may differ from those found in other continents. In four separate surveys across a wide area of New South Wales, it was tested whether there was a difference in the abundance or species richness captured by yellow- and white-coloured pan traps. In total, 1267 bees were collected, comprising 66 species, 50 of which are in the family Halictidae. In all surveys, yellow pan traps collected a significantly larger number and greater diversity of bees. Eight of the thirteen most common species were observed significantly more frequently (P < 0.01) in yellow pan traps, while the European honey bee (Apis mellifera) was found in larger numbers in white traps. Our results demonstrate that differently coloured traps collect different components of the Australian bee fauna. Therefore, a variety of pan colours should be used when sampling overall bee biodiversity, but specific colours may be more effective when targeting certain groups or species.