Comparison of the efficiency of the Onderstepoort- and Centres for Disease Control ultraviolet light traps for the collection of livestock associated Culicoides species in South Africa

Comparative monitoring of the abundance and distribution of Culicoides biting midges (Diptera: Ceratopogonidae), the biological vectors of the causative agents of several diseases of global veterinary importance, will be crucial in determining the risk of disease outbreak and spread. Ultraviolet (UV) suction traps have become the most frequent method used for the monitoring of Culicoides diversity and abundance. The current study compared the trapping efficiency of the two most used UV suction light traps, i.e., the Onderstepoort (OP)- and the Centres for Disease Control trap, for the collection of livestock associated Culicoides species in South Africa. The study confirmed the superiority of the OP trap and indicated a correlation in species composition and age grading results as determine with the two trap types. Substantial variations in the comparative trap efficiency, as found between areas and sites within an area, suggest that a universal conversion factor between the two trap types may not be advisable as it is unclear to what extent species composition and environmental factors may influence the conversion factor. Light traps, independent of trap model, can be considered acceptable for determining the serial comparison of population numbers for seasonal fluctuation and species abundance in distribution surveys.