Do Mosquito Traps Work?

The definitive study is Frick & Tallamy (1996) from the University of Delaware, which examined 13,789 insects electrocuted in six residential bug zappers over one season. Only 31 insects (0.22%) were biting flies or mosquitoes. Nearly half were aquatic midges; about 14% were beneficial insects including ladybugs, parasitic wasps, and ground beetles. The authors projected that the approximately 4 million zappers operating in U.S. yards would collectively kill around 71 billion non-target insects per year. The reason is simple: mosquitoes navigate to hosts using CO₂, heat, and lactic acid — not UV light. NH DHHS explicitly states bug zappers 'have not been shown to be useful in preventing mosquito bites.'

This CO₂ claim has not been independently verified — University of Wisconsin measurement reportedly detected no CO₂ output. Functionally, DynaTrap operates as a quiet zapper: UV light and a fan drawing insects into a catch basket. Independent product reviewers (Bob Vila, Reviewed.com) consistently report DynaTraps catching moths, midges, beetles, and occasionally bees — few mosquitoes. At $60–$200, it offers no advantage over a cheaper UV zapper for mosquito control.

This is technically a spatial repellent rather than a trap, but it is the only consumer-grade mosquito device with a strong peer-reviewed evidence base. Rodriguez et al. (2017) in the Journal of Insect Science found the metofluthrin clip-on was the only wearable device to significantly reduce mosquito attraction in wind-tunnel testing. Ogoma et al. (2023) in Malaria Journal found metofluthrin Thermacell nearly completely prevented Anopheles funestus landing indoors and cut outdoor landings approximately 10-fold within 10 meters. The 2020 IVCC expert review of spatial repellents documented 70–97% landing reductions across studies. Key limitation: wind above 5 mph significantly degrades the vapor protection zone. Best suited for still-air patio settings.

Gravid Aedes females enter a black bucket, pick up pyriproxyfen (an insect growth regulator) on a gauze strip, and carry it to neighboring breeding sites — a process called autodissemination — while also being infected with Beauveria bassiana fungus. Paris et al. (2023) in the Journal of Medical Entomology found 43% fewer eggs at 6 weeks and 50% average reduction in adult eclosion in Australian field trials. Tristao et al. (2025) in PLOS NTDs documented reduced positive ovitraps from 56.9% to 31.5% and a 56% reduction in eggs per trap in high-density Brazilian trial zones using 3,250 stations over 14 months. In2Care requires monthly professional servicing and is a licensed-applicator-only product in NH.

Kline (2002) in the Journal of the American Mosquito Control Association found Mosquito Magnets consistently captured large numbers of certain Aedes species in cage studies. However, AMCA notes that Salt Lake City Mosquito Abatement District testing showed the Mosquito Magnet 'captured enormous numbers of Ochlerotatus sierrensis... but few Culex pipiens, Culex tarsalis, or Ochlerotatus dorsalis.' This is a critical limitation for New Hampshire: Culex pipiens is the state's primary West Nile Virus vector, and it is among the species least reliably captured by propane traps. Recurring costs add up: propane (~$20 per refill every 21 days), attractant cartridges ($15–$30 every 21 days), plus the initial $700+ investment. Best suited for large open properties (≥1 acre) with continuous 24/7 operation targeting Aedes species.