Effects of lighting regimens on the emergence and numbers of Culicoides brevitarsis Kieffer (Diptera : Ceratopogonidae) in emergence chambers

Darkness inhibited the emergence of the biting midge, Culicoides brevitarsi s from bovine dung held in emergence chambers at a constant 25 degrees C. L ight had a positive effect on emergence and the numbers of C. brevitarsis e merging increased linearly to a maximum in the afternoon. Counts from colle ction containers above the chambers were an accurate estimate of the number s of adults that emerged in the chambers. Numbers emerging were highest at constant and natural light and were significantly lower at light:dark 9h:15 h and 8h:16h. The rearing of C. brevitarsis adults from dung to assess fiel d population densities preferably should be carried out under constant ligh t.