Improving light-trap efficiency for Culicoides spp. with light-emitting diodes.

The robustness of light traps used to monitor Culicoides spp. throughout Australia was improved with stainless steel and heavy duty plastic fittings. Printed circuit boards and light-dependent resistors were modified to be compatible with recent advances in electronics. In experiments with light-emitting diodes (LEDs), C. brevitarsis Kieffer was significantly attracted to green light. This species is the major vector of Akabane and bluetongue viruses in Australia and is the main target of a national monitoring programme using light traps. This response was significantly greater than the response to the incandescent lights currently used in the light traps. Catches of C. brevitarsis were also related to the intensity of the green LEDs. These were more effective than the currently used incandescent globes at intensities between 46% and 142% of the incandescent intensity. The response of seven other Culicoides spp. to the LEDs was also determined.