Comparison of black and white light for collecting Culicoides imicola and other livestock-associated Culicoides species in South Africa.

Comparison of the effectiveness of 8W fluorescent black and white light sources, in two 4x4 Latin squares (16 replicates) designs under South African conditions, showed black light to be up to three time more effective in collecting Culicoides imicola Kieffer (Diptera, Ceratopogonidae) and other South African Culicoides species. Four Culicoides species, which were collected in low numbers with black light, were not collected in traps equipped with the white light source. No significant difference was found in the parous rate of the C. imicola populations as determined by the two light sources. The study highlighted the superiority of black light as a preferred collection method for C. imicola, considered to be the most widespread and abundant vector of livestock orbiviruses. The results underline the need to develop and adopt standard techniques for measuring the variables of vectorial capacity.