Investigation of Culicoides spp. preference for light colour and source using light emitting diodes and fluorescent light

Abstract

Light colour and source preference testing has been conducted for C. brevitarsus in Australia but have not been performed in South Africa. Data from the Australian trials show an increased affinity for light from Light Emitting Diodes (LEDs) rather than incandescent light (the Australian Standard). Locally, the collection standard is an 8W fluorescent ultra-violet (UV) blacklight. A new trap was used to compare midge attractiveness to fluorescent and LED light sources as well as the colours: white, green and UV.
Results show a very high affinity for UV light. Catches from white and green light were not found to differ significantly and the interaction between light colour and source was not found to be significant. Possible trap development and action thresholds are discussed.

Keywords: Culicoides midge vector, African Horse Sickness, light colour, light emitting diodes