Improving efficiency of disease vector sampling in the field: An automatic solar-powered mosquito trapping system

Trapping mosquitoes to quantify their distribution and abundance is often a key step in monitoring dynamics of vector-borne diseases. This is the case in Hawaii, where avian malaria is devastating native forest birds that are highly susceptible to non-native diseases. However, mosquito trapping is difficult and labor intensive. A typical operation requires traps to be visited multiple times within a 24-hour period to control their active components and batteries. For example, traps for nocturnal mosquitoes require trap fans and carbon dioxide (CO2) tanks turned on in the evening and then turned off the following morning, with batteries changed frequently. For traps in very remote locations, this frequent attendance accrues considerable cost and personnel time. To help minimize field efforts required for maintaining mosquito trapping arrays, we developed an automated power system to operate the mosquito traps. The traps can be set to operate on a schedule using a built-in timer, eliminating the need for personnel to manually turn traps on and off. Additionally, this system is powered by a solar-recharged battery so that the system can run indefinitely in many field locations. We tested the system at ‘Āinahou Ranch in Hawai‘i Volcanoes National Park, Island of Hawai‘i, where we operated a trapping array continuously for over two years. Specifically, two types of traps were deployed at each location, one a gravid trap and another a CO2 trap. We provide a step-by-step guide on how to build the systems and describe how to deploy them in the field.