One man's rubbish is another man's treasure, or in this case, a field scientists.
Due to the small nature of Culicoides biting midges, and difficulties associated with colonising UK species of interest, relatively little is known about the potential for UK species to spread disease. We already know that several species of Culicoides can spread Schmallenberg virus and bluetongue virus here in the UK, however how these diseases manage to persist from one year to the next (or overwinter) is poorly understood. Light traps are used to monitor Culicoides activity and have been previously used to estimate population dynamics, however well-known biases exist for this trapping technique (including the attractiveness of the trap to different species, low rates of male Culicoides capture, variation in daytime activity being overlooked and potential aversion to light in infected Culicoides).
Emergence traps on the other hand collect everything that emerges from below them. For this study we wanted to collect Culicoides obsoletus, a known vector species that breeds in cattle dung. Across 2 years we collected and identified more than 96,000 Culicoides demonstrating that dung heaps represent an important overwintering habitat for these disease vector species. We also demonstrated that light suction traps are not a reliable indicator of emergence (rather they represent adult flight behaviour) and subsequently that there is no evidence of mass emergence in spring, rather mass flight and host seeking behaviour once conditions are favourable.
To read more about our findings you can access the paper here