Evaluating a Novel Method to Limit Non-Target Mortality in Attractive Toxic Sugar Bait Systems

Attractive toxic sugar baits (ATSB) exploit mosquito sugar-feeding as a control strategy, but their use has been hindered by non-target (pollinator) exposure, environmental degradation, and the difficulties of selectively administering toxicants to mosquitoes. We developed and evaluated a perforated bag-based ATSB system incorporating 200-300 microperforations (<0.25 mm in diameter) to selectively deliver toxicants in sugar water to mosquitoes while physically excluding non-target pollinators (i.e., butterflies and honey bees). In laboratory assays, the perforated bag design supported high mosquito feeding success (87%) and rapid mortality (100% within 24 h) when combined with propylene glycol or dinotefuran, without deterring feeding behavior. Butterflies and honey bees were unable to access sugar solutions through the perforated bag, demonstrating selectivity toward mosquitoes due to differences in mouthpart morphology compared to non-targets. Semi-field trials showed that integrating perforated ATSB system into passive traps did not reduce capture rates of gravid Culex quinquefasciatus or host-seeking Aedes aegypti, while inducing near complete mosquito mortality (>90%) following capture. Our results indicate that perforated bag-based ATSB systems incorporated into passive traps can target mosquitoes across multiple physiological states while minimizing the non-target risk. This platform provides promising and environmentally responsible integration of ATSB deployment into mosquito surveillance and control programs.